1. Describe how the DHCP lease is obtained. It’s a four-step process consisting of (a) IP request, (b) IP offer, (c) IP selection and (d) acknowledgement.
2. I can’t seem to access the Internet, don’t have any access to the corporate network and on ipconfig my address is 169.254.*.*. What happened? The 169.254.*.* netmask is assigned to Windows machines running 98/2000/XP if the DHCP server is not available. The name for the technology is APIPA (Automatic Private Internet Protocol Addressing).
3. We’ve installed a new Windows-based DHCP server, however, the users do not seem to be getting DHCP leases off of it. The server must be authorized first with the Active Directory.
4. How can you force the client to give up the dhcp lease if you have access to the client PC? ipconfig /release
5. What authentication options do Windows 2000 Servers have for remote clients? PAP, SPAP, CHAP, MS-CHAP and EAP.
6. What are the networking protocol options for the Windows clients if for some reason you do not want to use TCP/IP? NWLink (Novell), NetBEUI, AppleTalk (Apple).
7. What is data link layer in the OSI reference model responsible for? Data link layer is located above the physical layer, but below the network layer. Taking raw data bits and packaging them into frames. The network layer will be responsible for addressing the frames, while the physical layer is responsible for retrieving and sending raw data bits.
8. What is binding order? The order by which the network protocols are used for client-server communications. The most frequently used protocols should be at the top.
9. How do cryptography-based keys ensure the validity of data transferred across the network? Each IP packet is assigned a checksum, so if the checksums do not match on both receiving and transmitting ends, the data was modified or corrupted.
10. Should we deploy IPSEC-based security or certificate-based security? They are really two different technologies. IPSec secures the TCP/IP communication and protects the integrity of the packets. Certificate-based security ensures the validity of authenticated clients and servers.
11. What is LMHOSTS file? It’s a file stored on a host machine that is used to resolve NetBIOS to specific IP addresses.
12. What’s the difference between forward lookup and reverse lookup in DNS? Forward lookup is name-to-address; the reverse lookup is address-to-name.
13. How can you recover a file encrypted using EFS? Use the domain recovery agent.
IIS QUESTIONS
This came in the mail from the reader who recently went through a job interview process. He didn’t mention the company name.
1. How would you remotely administer IIS?
2. What is RAID? What is it used for?
3. How would you go about securing IIS and MS-SQL Server?
WINDOWS 2000 ADMINISTRATION QUESTIONS
1. Explain hidden shares. Hidden or administrative shares are share names with a dollar sign ($) appended to their names. Administrative shares are usually created automatically for the root of each drive letter. They do not display in the network browse list.
2. How do the permissions work in Windows 2000? What permissions does folder inherit from the parent? When you combine NTFS permissions based on users and their group memberships, the least restrictive permissions take precedence. However, explicit Deny entries always override Allow entries.
3. Why can’t I encrypt a compressed file on Windows 2000? You can either compress it or encrypt it, but not both.
4. If I rename an account, what must I do to make sure the renamed account has the same permissions as the original one? Nothing, it’s all maintained automatically.
5. What’s the most powerful group on a Windows system? Administrators.
6. What are the accessibility features in Windows 2000? StickyKeys, FilterKeys Narrator, Magnifier, and On-Screen Keyboard.
7. Why can’t I get to the Fax Service Management console? You can only see it if a fax had been installed.
8. What do I need to ensure before deploying an application via a Group Policy? Make sure it’s either an MSI file, or contains a ZAP file for Group Policy.
9. How do you configure mandatory profiles? Rename ntuser.dat to ntuser.man
10. I can’t get multiple displays to work in Windows 2000. Multiple displays have to use peripheral connection interface (PCI) or Accelerated Graphics Port (AGP) port devices to work properly with Windows 2000.
11. What’s a maximum number of processors Win2k supports? 2
12. I had some NTFS volumes under my Windows NT installation. What happened to NTFS after Win 2k installation? It got upgraded to NTFS 5.
13. How do you convert a drive from FAT/FAT32 to NTFS from the command line? convert c: /fs:ntfs
14. Explain APIPA. Auto Private IP Addressing (APIPA) takes effect on Windows 2000 Professional computers if no DHCP server can be contacted. APIPA assigns the computer an IP address within the range of 169.254.0.0 through 169.254.255.254 with a subnet mask of 255.255.0.0.
15. How does Internet Connection Sharing work on Windows 2000? Internet Connection Sharing (ICS) uses the DHCP Allocator service to assign dynamic IP addresses to clients on the LAN within the range of 192.168.0.2 through 192.168.0.254. In addition, the DNS Proxy service becomes enabled when you implement ICS.
WHAT ARE THE DIFFERENCE IN WINDOWS NT SERVER, 2000SERVER AND 2003 SERVER AND NOW WIN SERVER2008
NT SAM database is a flat database. Where as in windows 2000 active directory database is a hierarchical database.
In Windows NT only PDC is having writable copy of SAM database but the BDC is only read only database. In case of
Windows 2000 both DC and ADC is having write copy of the database
Windows NT will not support FAT32 file system. Windows 2000 supports FAT32
Default authentication protocol in NT is NTLM (NT LAN manager). In windows 2000 default authentication protocol is Kerberos V5.
Windows 2000 depends and Integrated with DNS. NT user NetBIOS names
Active Directory can be backed up easily with System state data
Application Server mode is introduced in windows 2003
Possible to configure stub zones in windows 2003 DNS
Volume shadow copy services is introduced
Windows 2003 gives an option to replicate DNS data b/w all DNS servers in forest or All DNS servers in the domain.
PDC contains a write copy of SAM database where as BDC contains read only copy of SAM database. It is not possible to reset a password or create objects with out PDC in Windows NT.
There is no difference between in DC and ADC both contains write copy of AD. Both can also handles FSMO roles (If transfers from DC to ADC). It is just for identification.
Functionality wise there is no difference windows 2008 is fully script based software with more group policies and permissions win 2000 domain name can't change. But in 2003 server we can change.
In 2003 we can able to add more than 220 group policy but in 2000 it not possible.
54 SCREENING QUESTIONS FOR WINDOWS ADMIN
1. What is Active Directory?
2. What is LDAP?
3. Can you connect Active Directory to other 3rd-party Directory Services? Name a few options.
4. Where is the AD database held? What other folders are related to AD?
5. What is the SYSVOL folder?
6. Name the AD NCs and replication issues for each NC
7. What are application partitions? When do I use them
8. How do you create a new application partition
9. How do you view replication properties for AD partitions and DCs?
10. What is the Global Catalog?
11. How do you view all the GCs in the forest?
12. Why not make all DCs in a large forest as GCs?
13. Trying to look at the Schema, how can I do that?
14. What are the Support Tools? Why do I need them?
15. What is LDP? What is REPLMON? What is ADSIEDIT? What is NETDOM? What is REPADMIN?
16. What are sites? What are they used for?
17. What’s the difference between a site link’s schedule and interval?
18. What is the KCC?
19. What is the ISTG? Who has that role by default?
20. What are the requirements for installing AD on a new server?
21. What can you do to promote a server to DC if you’re in a remote location with slow WAN link?
22. How can you forcibly remove AD from a server, and what do you do later? • Can I get user passwords from the AD database?
23. What tool would I use to try to grab security related packets from the wire?
24. Name some OU design considerations.
25. What is tombstone lifetime attribute?
26. What do you do to install a new Windows 2003 DC in a Windows 2000 AD?
27. What do you do to install a new Windows 2003 R2 DC in a Windows 2003 AD?
28. How would you find all users that have not logged on since last month?
29. What are the DS* commands?
30. What’s the difference between LDIFDE and CSVDE? Usage considerations?
31. What are the FSMO roles? Who has them by default? What happens when each one fails?
32. What FSMO placement considerations do you know of?
33. I want to look at the RID allocation table for a DC. What do I do?
34. What’s the difference between transferring a FSMO role and seizing one? Which one should you NOT seize? Why?
35. How do you configure a “stand-by operation master” for any of the roles?
36. How do you backup AD?
37. How do you restore AD?
38. How do you change the DS Restore admin password?
39. Why can’t you restore a DC that was backed up 4 months ago?
40. What are GPOs?
41. What is the order in which GPOs are applied?
42. Name a few benefits of using GPMC.
43. What are the GPC and the GPT? Where can I find them?
44. What are GPO links? What special things can I do to them?
45. What can I do to prevent inheritance from above?
46. How can I override blocking of inheritance?
47. How can you determine what GPO was and was not applied for a user? Name a few ways to do that.
48. A user claims he did not receive a GPO, yet his user and computer accounts are in the right OU, and everyone else there gets the GPO. What will you look for?
49. Name a few differences in Vista GPOs
50. Name some GPO settings in the computer and user parts.
51. What are administrative templates?
52. What’s the difference between software publishing and assigning?
53. Can I deploy non-MSI software with GPO?
54. You want to standardize the desktop environments (wallpaper, My Documents, Start menu, printers etc.) on the computers in one department. How would you do that?
29 RESPONSES TO “54 SCREENING QUESTIONS FOR WINDOWS ADMIN”
Que.: What is Active Directory?
Ans. Active Directory is a Meta Data. Active Directory is a data base which stores a data base like your user information, computer information and also other network object info. It has capabilities to manage and administer the complete Network which connect with AD.
Que.: What is the Global Catalog?
Ans.: Global Catalog is a server which maintains the information about multiple domains with trust relationship agreement.
Que: What is Active
Directory?
Ans:
Active Directory service is an extensible and scalable directory service
that enables you to manage network resources efficiently.
Q01: What is Active
Directory?
Ans:
Active Directory is directory service that stores information about objects on a
network and makes this information available to users and network
administrators.
Active Directory gives network users access to permitted
resources anywhere on the network using a single logon process.
It provides
network administrators with an intuitive, hierarchical view of the network and a
single point of administration
3for all network objects.
Q; What is active directory?
Ans: active directory is a domain controller which is use to authenticate and administrate the group of computer, user, server etc. remotely. All the policies and security will be applicable on the client machine which one is join the domain. And all this policies and security is defined in active directory.
Q2: What is LDAP?
Ans2: LDAP (light weight directory
access protocol) is an internet protocol which Email and other services is used
to look up information from the server.
Q 18: What is KCC?
Ans 18: KCC (knowledge
consistency checker) is used to generate replication topology for inter site
replication and for intrasite replication. With in site replication traffic are
done via remote procedure calls over ip, while between sites it is done through
either RPC or SMTP.
Q 10: What is Global Catalog Server?
The global
catalog is a distributed data repository that contains a searchable, partial
representation of every object in every domain in a multidomain Active Directory
forest. The global catalog is stored on domain controllers that have been
designated as global catalog servers and is distributed through multimaster
replication. Searches that are directed to the global catalog are faster because
they do not involve referrals to different domain controllers.
Q; What is active directory?
Active directory is a
domain controller which is use to authenticate and administrate the group of
computer, user, server etc. remotely. All the policies and security will be
applicable on the client machine which one is join the domain. And all this
policies and security is defined in active directory.
Q 4: Where is the AD database held? What other folders are related to AD?
A 4: The AD data base is store in NTDS.DIT file
Q 5: What is the SYSVOL folder?
A 5; The
sysVOL folder stores the server’s copy of the domain’s public files. The
contents such as group policy, users etc of the sysvol folder are replicated to
all domain controllers in the domain.
Q 19: What is the ISTG? Who has that role by default?
A 19: Windows 2000 Domain controllers each create Active Directory Replication connection objects representing inbound replication from intra-site replication partners. For inter-site replication, one domain controller per site has the responsibility of evaluating the inter-site replication topology and creating Active Directory Replication Connection objects for appropriate bridgehead servers within its site. The domain controller in each site that owns this role is referred to as the Inter-Site Topology Generator (ISTG).
Q: 15 What is LDP? What is REPLMON? What is ADSIEDIT?
What is NETDOM? What is REPADMIN?
A 15: LDP: Label Distribution Protocol
(LDP) is often used to establish MPLS LSPs when traffic engineering is not
required. It establishes LSPs that follow the existing IP routing, and is
particularly well suited for establishing a full mesh of LSPs between all of the
routers on the network.
Replmon: Replmon displays information about Active
Directory Replication.
ADSIEDIT: ADSIEdit is a Microsoft Management Console
(MMC) snap-in that acts as a low-level editor for Active Directory. It is a
Graphical User Interface (GUI) tool. Network administrators can use it for
common administrative tasks such as adding, deleting, and moving objects with a
directory service. The attributes for each object can be edited or deleted by
using this tool. ADSIEdit uses the ADSI application programming interfaces
(APIs) to access Active Directory. The following are the required files for
using this tool: ADSIEDIT.DLL
ADSIEDIT.MSCNETDOM: NETDOM is a command-line
tool that allows management of Windows domains and trust relationships. It is
used for batch management of trusts, joining computers to domains, verifying
trusts, and secure channels.
REPADMIN:
This command-line tool assists
administrators in diagnosing replication problems between Windows domain
controllers. Administrators can use Repadmin to view the replication topology
(sometimes referred to as RepsFrom and RepsTo) as seen from the perspective of
each domain controller. In addition, Repadmin can be used to manually create the
replication topology (although in normal practice this should not be necessary),
to force replication events between domain controllers, and to view both the
replication metadata and up-to-datedness vectors.
Q 36: How to take the backup of AD?
A 36 : for
taking backup of active directory you have to do this :
first go
to START -> PROGRAM ->ACCESORIES -> SYSTEM TOOLS -> BACKUP
when the backup screen is flash then take the backup of SYSTEM STATE it will
take the backup of all the necessary information about the system including AD
backup , DNS ETC.
Q 37: how to restore the AD?
A 37: For this do
the same as above in the question 36 but in place of backup you select the
restore option and restore the system state.
Q 19: What is the ISTG? Who has that role by
default?
A 19: Inter-Site Topology Generator (istg) is responsible
for managing the inbound replication connection objects for all bridgehead
servers in the site in which it is located. This domain controller is known as
the Inter-Site Topology Generator (ISTG). The domain controller holding this
role may not necessarily also is a bridgehead server.
Q 29: What are the DS* commands A 29: You really are spoilt for choice when it comes to scripting tools for creating Active Directory objects. In addition to CSVDE, LDIFDE and VBScript, we now have the following DS commands: the da family built in utility DSmod - modify Active Directory attributesDSrm - to delete Active Directory objectsDSmove - to relocate objectsDSadd - create new accountsDSquery - to find objects that match your query attributesDSget - list the properties of an object
Q 30 :What’s the difference between LDIFDE and CSVDE?
Usage considerations?
A 30 : CSVDE is a command that can be used to import
and export objects to and from the AD into a CSV-formatted file. A CSV (Comma
Separated Value) file is a file easily readable in Excel. I will not go to
length into this powerful command, but I will show you some basic samples of how
to import a large number of users into your AD. Of course, as with the DSADD
command, CSVDE can do more than just import users. Consult your help file for
more info.
Like CSVDE, LDIFDE is a command that can be used to import and
export objects to and from the AD into a LDIF-formatted file. A LDIF (LDAP Data
Interchange Format) file is a file easily readable in any text editor, however
it is not readable in programs like Excel. The major difference between CSVDE
and LDIFDE (besides the file format) is the fact that LDIFDE can be used to edit
and delete existing AD objects (not just users), while CSVDE can only import and
export objects.
Q 25 : What is tombstone lifetime attribute?
A 25 : The number of days before a deleted object is removed from the directory services. This assists in removing objects from replicated servers and preventing restores from reintroducing a deleted object. This value is in the Directory Service object in the configuration NIC.
You want to standardize the desktop environments (wallpaper, My Documents, Start menu, printers etc.) on the computers in one department. How would you do that? How it is possibal
(20)What
are the requirements for installing AD on a new server?
Ans:1)The Domain
structure2)The Domain Name3)storage location of the database and log
file4)Location of the shared system volume folder5)DNS config Methode6)DNS
configuration
7. What are application partitions? When do I use them.
Ans: AN application diretcory partition is a directory partition that is replicated only to specific domain controller.Only domain controller running windows Server 2003 can host a replica of application directory partition.
Using an application directory partition provides redundany,availabiltiy or fault tolerance by replicating data to specific domain controller pr any set of domain controllers anywhere in the forest
Q:You want to standardize the desktop environments (wallpaper, My Documents, Start menu, printers etc.) on the computers in one department. How would you do that? How it is possibal.
Ans:Login on client as Domain Admin user change whatever you need add printers etc go to system-User profiles copy this user profile to any location by select Everyone in permitted to use after copy change ntuser.dat to ntuser.man and assgin this path under user profile
Q. 8. How do you create a new application partition
ANS:Use the DnsCmd command to create an application
directory partition. To do this, use the following syntax:
DnsCmd ServerName
/CreateDirectoryPartition FQDN of partition
Global catalog provides a central repository of domain
information for the forest by storing partial replicas of all domain directory
partitions. These partial replicas are distributed by multimaster replication to
all global catalog servers in a forest.
Its also used in universal global
membership.
How do you view all the GCs in the forest?
Ans: C:\>repadmin /showreps
<domain_controller>
where domain_controller is the DC you want to query
to determine whether it’s a GC. The output will include the text DSA Options:
IS_GC if the DC is a GC. . . .
Trying to look at the Schema, how can I do that
Ans: type “adsiedit.msc” in run or command prompt
Q. Can you connect Active Directory to other 3rd-party Directory Services? Name a few options.
Ans. Yes, you can use dirXML or LDAP to connect to other directories In Novell you can use E-directory
PAGE FILE AND VIRTUAL MEMORY
Page File Is Storage Space For The Virtual Memory, Page File Uses Hard Disk Space As a Memory To Provide Memory Allocation..
DIFFERENCE BETWEEN DNS IN WINDOWS2000& WINDOWS2003
We can rename or moved the domain name without rebulding in windows 2003 server,but in windows 2000 server, we can't do that.
Shadow copy feature available in windows2003 server but not in windows2000 server.A new tools to recover files.
There are 220 new group polices are added in windows2003 server over windows2000 server.
In windows2000 server support maximum 10 users access shared folders at a time through network, but windows2003 server no limitation.
Windows 2003 server includes IIS in it.
WINDOWS ADMIN INTERVIEW QUESTIONS
1. Describe how the DHCP lease is
obtained.
It’s a
four-step process consisting of (a) IP request, (b) IP offer, © IP selection and
(d) acknowledgement.
2. I can’t
seem to access the Internet, don’t have any access to the corporate network and
on ipconfig my address is 169.254.*.*. What
happened?
The
169.254.*.* netmask is assigned to Windows machines running 98/2000/XP if the
DHCP server is not available. The name for the technology is APIPA (Automatic
Private Internet Protocol Addressing).
3. We’ve installed a new Windows-based DHCP server, however, the users do not seem to be getting DHCP leases off of it. The server must be authorized first with the Active Directory.
4. How can
you force the client to give up the dhcp lease if you have access to the client
PC?
ipconfig
/release
5. What
authentication options do Windows 2000 Servers have for remote
clients?
PAP,
SPAP, CHAP, MS-CHAP and EAP.
6. What are the networking protocol options for the Windows clients if for some reason you do not want to use TCP/IP? NWLink (Novell), NetBEUI, AppleTalk (Apple).
7. What is
data link layer in the OSI reference model responsible for? Data link layer is
located above the physical layer, but below the network
layer.
Taking raw
data bits and packaging them into frames. The network layer will be responsible
for addressing the frames, while the physical layer is reponsible for retrieving
and sending raw data bits.
8. What is
binding order?
The
order by which the network protocols are used for client-server communications.
The most frequently used protocols should be at the top.
9. How do
cryptography-based keys ensure the validity of data transferred across the
network?
Each IP
packet is assigned a checksum, so if the checksums do not match on both
receiving and transmitting ends, the data was modified or corrupted.
10. Should
we deploy IPSEC-based security or certificate-based security?
They are really
two different technologies. IPSec secures the TCP/IP communication and protects
the integrity of the packets. Certificate-based security ensures the validity of
authenticated clients and servers.
11. What is
LMHOSTS file?
It’s
a file stored on a host machine that is used to resolve NetBIOS to specific IP
addresses.
12. What’s
the difference between forward lookup and reverse lookup in
DNS?
Forward
lookup is name-to-address, the reverse lookup is address-to-name.
13. How can
you recover a file encrypted using EFS?
Use the domain recovery agent.
WINDOWS SERVER 2003 INTERVIEW AND CERTIFICATION QUESTIONS
1. How do you double-boot a Win 2003 server box? The Boot.ini file is set as read-only, system, and hidden to prevent unwanted editing. To change the Boot.ini timeout and default settings, use the System option in Control Panel from the Advanced tab and select Startup.
2. What do you do if earlier application doesn’t run on Windows Server 2003? When an application that ran on an earlier legacy version of Windows cannot be loaded during the setup function or if it later malfunctions, you must run the compatibility mode function. This is accomplished by right-clicking the application or setup program and selecting Properties –> Compatibility –>selecting the previously supported operating system.
3. If you uninstall Windows Server 2003, which operating systems can you revert to? Win ME, Win 98, 2000, XP. Note, however, that you cannot upgrade from ME and 98 to Windows Server 2003.
4. How do you get to Internet Firewall settings? Start –> Control Panel –> Network and Internet Connections –> Network Connections.
5. What are the Windows Server 2003 keyboard shortcuts? Winkey opens or closes the Start menu. Winkey + BREAK displays the System Properties dialog box. Winkey + TAB moves the focus to the next application in the taskbar. Winkey + SHIFT + TAB moves the focus to the previous application in the taskbar. Winkey + B moves the focus to the notification area. Winkey + D shows the desktop. Winkey + E opens Windows Explorer showing My Computer. Winkey + F opens the Search panel. Winkey + CTRL + F opens the Search panel with Search for Computers module selected. Winkey + F1 opens Help. Winkey + M minimizes all. Winkey + SHIFT+ M undoes minimization. Winkey + R opens Run dialog. Winkey + U opens the Utility Manager. Winkey + L locks the computer.
6. What is Active Directory? Active Directory is a network-based object store and service that locates and manages resources, and makes these resources available to authorized users and groups. An underlying principle of the Active Directory is that everything is considered an object—people, servers, workstations, printers, documents, and devices. Each object has certain attributes and its own security access control list (ACL).
7. Where are the Windows NT Primary Domain Controller (PDC) and its Backup Domain Controller (BDC) in Server 2003? The Active Directory replaces them. Now all domain controllers share a multimaster peer-to-peer read and write relationship that hosts copies of the Active Directory.
8. How long does it take for security changes to be replicated among the domain controllers? Security-related modifications are replicated within a site immediately. These changes include account and individual user lockout policies, changes to password policies, changes to computer account passwords, and modifications to the Local Security Authority (LSA).
9. What’s new in Windows Server 2003 regarding the DNS management? When DC promotion occurs with an existing forest, the Active Directory Installation Wizard contacts an existing DC to update the directory and replicate from the DC the required portions of the directory. If the wizard fails to locate a DC, it performs debugging and reports what caused the failure and how to fix the problem. In order to be located on a network, every DC must register in DNS DC locator DNS records. The Active Directory Installation Wizard verifies a proper configuration of the DNS infrastructure. All DNS configuration debugging and reporting activity is done with the Active Directory Installation Wizard.
10. When should you create a forest? Organizations that operate on radically different bases may require separate trees with distinct namespaces. Unique trade or brand names often give rise to separate DNS identities. Organizations merge or are acquired and naming continuity is desired. Organizations form partnerships and joint ventures. While access to common resources is desired, a separately defined tree can enforce more direct administrative and security restrictions.
11. How can you authenticate between forests? Four types of authentication are used across forests: (1) Kerberos and NTLM network logon for remote access to a server in another forest; (2) Kerberos and NTLM interactive logon for physical logon outside the user’s home forest; (3) Kerberos delegation to N-tier application in another forest; and (4) user principal name (UPN) credentials
12. What snap-in administrative tools are available for Active Directory? Active Directory Domains and Trusts Manager, Active Directory Sites and Services Manager, Active Directory Users and Group Manager, Active Directory Replication (optional, available from the Resource Kit), Active Directory Schema Manager (optional, available from adminpak)
13. What types of classes exist in Windows Server 2003 Active Directory?
1. Structural class. The structural class is important to the system administrator in that it is the only type from which new Active Directory objects are created. Structural classes are developed from either the modification of an existing structural type or the use of one or more abstract classes.
2. Abstract class. Abstract classes are so named because they take the form of templates that actually create other templates (abstracts) and structural and auxiliary classes. Think of abstract classes as frameworks for the defining objects.
3. Auxiliary class. The auxiliary class is a list of attributes. Rather than apply numerous attributes when creating a structural class, it provides a streamlined alternative by applying a combination of attributes with a single include action.
4. 88 class. The 88 class includes object classes defined prior to 1993, when the 1988 X.500 specification was adopted. This type does not use the structural, abstract, and auxiliary definitions, nor is it in common use for the development of objects in Windows Server 2003 environments.
14. How do you delete a lingering object? Windows Server 2003 provides a command called Repadmin that provides the ability to delete lingering objects in the Active Directory.
15. What is Global Catalog? The Global Catalog authenticates network user logons and fields inquiries about objects across a forest or tree. Every domain has at least one GC that is hosted on a domain controller. In Windows 2000, there was typically one GC on every site in order to prevent user logon failures across the network.
16. How is user account security established in Windows Server 2003? When an account is created, it is given a unique access number known as a security identifier (SID). Every group to which the user belongs has an associated SID. The user and related group SIDs together form the user account’s security token, which determines access levels to objects throughout the system and network. SIDs from the security token are mapped to the access control list (ACL) of any object the user attempts to access.
17. If I delete a user and then create a new account with the same username and password, would the SID and permissions stay the same? No. If you delete a user account and attempt to recreate it with the same user name and password, the SID will be different.
18. What do you do with secure sign-ons in an organization with many roaming users? Credential Management feature of Windows Server 2003 provides a consistent single sign-on experience for users. This can be useful for roaming users who move between computer systems. The Credential Management feature provides a secure store of user credentials that includes passwords and X.509 certificates.
19. Anything special you should do when adding a user that has a Mac? “Save password as encrypted clear text” must be selected on User Properties Account Tab Options, since the Macs only store their passwords that way.
20. What remote access options does Windows Server 2003 support? Dial-in, VPN, dial-in with callback.
21. Where are the documents and settings for the roaming profile stored? All the documents and environmental settings for the roaming user are stored locally on the system, and, when the user logs off, all changes to the locally stored profile are copied to the shared server folder. Therefore, the first time a roaming user logs on to a new system the logon process may take some time, depending on how large his profile folder is.
22. Where are the settings for all the users stored on a given machine? \Document and Settings\All Users
23. What languages can you use for log-on scripts? JavaScipt, VBScript, DOS batch files (.com, .bat, or even .exe)
24. What’s the difference between local, global and universal groups? Domain local groups assign access permissions to global domain groups for local domain resources. Global groups provide access to resources in other trusted domains. Universal groups grant access to resources in all trusted domains.
25. I am trying to create a new universal user group. Why can’t I? Universal groups are allowed only in native-mode Windows Server 2003 environments. Native mode requires that all domain controllers be promoted to Windows Server 2003 Active Directory.
26. What is LSDOU? It’s group policy inheritance model, where the policies are applied to Local machines, Sites, Domains and Organizational Units.
27. Why doesn’t LSDOU work under Windows NT? If the NTConfig.pol file exist, it has the highest priority among the numerous policies.
28. Where are group policies stored? %SystemRoot%System32\GroupPolicy
29. What is GPT and GPC? Group policy template and group policy container.
30. Where is GPT stored? %SystemRoot%\SYSVOL\sysvol\domainname\Policies\GUID
31. You change the group policies, and now the computer and user settings are in conflict. Which one has the highest priority? The computer settings take priority.
32. You want to set up remote installation procedure, but do not want the user to gain access over it. What do you do? gponame–> User Configuration–> Windows Settings–> Remote Installation Services–> Choice Options is your friend.
33. What’s contained in administrative template conf.adm? Microsoft NetMeeting policies
34. How can you restrict running certain applications on a machine? Via group policy, security settings for the group, then Software Restriction Policies.
35. You need to automatically install an app, but MSI file is not available. What do you do? A .zap text file can be used to add applications using the Software Installer, rather than the Windows Installer.
36. What’s the difference between Software Installer and Windows Installer? The former has fewer privileges and will probably require user intervention. Plus, it uses .zap files.
37. What can be restricted on Windows Server 2003 that wasn’t there in previous products? Group Policy in Windows Server 2003 determines a users right to modify network and dial-up TCP/IP properties. Users may be selectively restricted from modifying their IP address and other network configuration parameters.
38. How frequently is the client policy refreshed? 90 minutes give or take.
39. Where is secedit? It’s now gpupdate.
40. You want to create a new group policy but do not wish to inherit. Make sure you check Block inheritance among the options when creating the policy.
41. What is “tattooing” the Registry? The user can view and modify user preferences that are not stored in maintained portions of the Registry. If the group policy is removed or changed, the user preference will persist in the Registry.
42. How do you fight tattooing in NT/2000 installations? You can’t.
43. How do you fight tattooing in 2003 installations? User Configuration - Administrative Templates - System - Group Policy - enable - Enforce Show Policies Only.
WHAT IS THE DIFFERENCE BETWEEN X86 AND I386 COMPUTER
X86 Is A Hardware Architecture Used By Intel Based CPU's While I386 Is The File Folder Resides In Windows Installation CD, Contains All The Necessary Windows Installation Files.
x86 refers to a popular set of instructions most
commonly used in processors from Intel, AMD, VIA,
and others. It usually implies a binary compatibility with the 32-bit
instruction set of the 80386 (a.k.a. i386).
i386 (as eluded to above) is
the common name for the Intel386 (or 80386) based PCs. It is sometimes
emphasized as x86-32 (for 32-bit) and x86-64 (also called x64 - for
64-bit).
INTERRUPT "TRAP" WHAT IS THIS TRAP?
There are two hinderances to a process. Interrupt and
trap.
Interrupt is when the process needs some I/O services whereas trap
occurs due to some fault or exception in the code.
How does multithreading take place on a computer with a single CPU
The operating system's task scheduler allocates execution time to multiple tasks. Byquickly switching between executing tasks, it creates the impression that tasks executesequentially.
By quickly switching among executing tasks, it creates the impression that the tasks execute simultaneously. If it didn't switch among the tasks, they would execute sequentially.
multi-threading has two forms, theory and reality. In theory, multi-threading is suppose to be the same as "multi-tasking" which means do two different task at the same time. Not possible on a single CPU unless you consider GPU and ALU which generally we do not (consider them). In reality, multi-threading does more than create an illusion, it allows computers to shut down a program in infinite loop by creating another thread so CPU executes one iteration of the loop, switch to the kill thread and terminates the loop. Multi-tasking was suppose to do that but not as well handled.
Hyperthreading processors have more than one execution units but only one processor core, thats how multiple tasks are performed simultaneously
what is the difference between blocking and waiting state of process ?
I think blocking state of a process is that state when it reaches to that state cannot be regained, but in case of wating state it can go in blocked state or go in running state again. Overall blocked state will be starvation state of a process.
A "waiting" process has been loaded into main memory
and is waiting execution on a CPU.
When a process is "blocked" on a resource
(such as a file,
a semaphore or a device), it will be removed from the CPU (as a blocked process
cannot continue execution) and will be in the blocked state.
A blocking state is the state in which the process is
waiting for some operation to get completed.It can be an I/O operaion,or some
Inter-Process-communication. The process can not execute furthur without these
signals.
A waiting state is the state in which the process is ready to run
but the processor is
not idle.
When the operation on the blocked process complete, it will move in
to the waiting state.
A process is said to be in waiting
state when it is queuing in the main memory for its turn to be
executed. Whereas, the process enters a blocked
state in case of any interrupt or due to unavailability of
resources. If it is no more in execution for a long time , it is
swapped out of main memory and called back when the requested resource is
available.
Important point: A process
cannot enter running state from blocked state. The process first has to go to
the waiting state and then to running state.
I hope that answers the
question.
WHAT IS SUPERSCOPE?
A superscope is an administrative feature of DHCP servers running Windows Server 2003 that you can create and manage through the DHCP console. Using a superscope, you can group multiple scopes as a single administrative entity. With this feature, a DHCP server can:
Support DHCP clients on a single physical network segment (such as a single Ethernet LAN segment) where multiple logical IP networks are used. When more than one logical IP network is used on each physical subnet or network, such configurations are often called multinets.
Support remote DHCP clients located on the far side of DHCP and BOOTP relay agents (where the network on the far side of the relay agent uses multinets).
FSMO- Flexible Single Master Operations.
What are Operation Masters ?
When a change is made to a domain, the change is replicated among all domain controllers in the domain. Some changes, such as changes made to the schema, are replicated across all the domains in the forest. This replication is known as multi-master replication. During multi-master replication, a replication conflict can occur if concurrent originating updates are performed on the same data on two different domain controllers. To avoid replication conflicts for some of the most important changes in Active Directory, for example the addition of a new domain or a change to the forest-wide schema, some operations are performed in single master fashion so that they are not allowed to occur at different places in the network at the same time. With single master replication, you designate specific domain controllers as the only domain controller on which certain directory changes can be made. Operations that are performed in a single-master fashion are grouped together into specific roles within the forest or within a domain. These roles are called operations master roles.
For each operations master role, only the domain controller that holds that role can make the associated directory changes. The domain controller responsible for a particular role is called an operations master for that role. Active Directory stores information about which domain controller holds a specific role.
Operations master roles : The five operations master roles are:
- Schema Master
- Domain Naming master
- PDC Emulator
- RID Master
- Infrastructure Master.
These Operations master roles are either forest-wide or domain-wide.
Forest-Wide Roles:
- Forest-wide roles are unique for a forest. The schema master and the domain naming master are forest-wide roles. This means that there is only one schema master and one domain naming master in the entire forest.
- Schema master The schema master controls all updates to the schema. The schema contains the master list of object classes and attributes that are used to create all Active Directory objects, such as computers, users, and printers.
- Domain naming master The domain naming master controls the addition or removal of domains in the forest. There is only one domain naming master for each forest. There is only the domain controller that holds domain naming master role has the right to add the new domain to the forest.
Domain-Wide Roles :
- Domain-wide roles are unique for each domain in a forest. The PDC emulator, the RID master, and the infrastructure master are domain-wide roles. This means that each domain in a forest has its own PDC emulator, RID master, and infrastructure master.
- Primary domain controller emulator The primary domain controller (PDC) emulator acts as a Windows NT PDC to support any backup domain controllers (BDCs) running Windows NT within a mixed-mode domain. A mixed-mode domain is a domain that has domain controllers that run Windows NT 4.0. The PDC emulator is the first domain controller that is created in a new domain.
- Relative identifier master When a new object, such as a user, group, or computer, is created the domain controller creates a new security principal that represents the object, and assigns the object a unique security identifier (SID). This SID consists of a domain SID, which is the same for all security principals created in the domain, and a relative identifier (RID), which is unique for each security principal created in the domain. The RID master allocates blocks of RIDs to each domain controller in the domain, and these are then assigned to objects that are created.
- Infrastructure master Active Directory allows objects, such as users, to be moved from one domain to another. When objects are moved, the infrastructure master is used to update object references in its domain that point to the object in another domain. The object reference contains the object.s globally identifier (GUID), distinguished name, and a SID. The distinguished name and SID on the object reference are periodically updated to reflect changes made to the actual object. These changes include moves within domains as well as the deletion of the object.
Operations Master Roles by Individual
Active Directory defines five operations master roles: the schema master, domain naming master, primary domain controller (PDC) emulator, relative identifier (RID) master, and the infrastructure master. This lesson explains the purpose of each of these operations master roles.
Schema Master
Introduction
An Active Directory schema defines the kinds of objects.and the types of information about those objects.that you can store in Active Directory. The definitions are stored as objects so that Active Directory can manage the schema objects with the object management operations that its uses to manage other objects in the directory.
Roles performed by the schema master
The schema master performs the following roles:
- Controls all originating updates to the schema.
- Contains the master list of object classes and attributes that are used to create all Active Directory objects.
- Replicates updates to the Active Directory schema to all domain controllers in the forest by using standard replication of the schema partition.
- Allows only the members of the schema Admin group to make modifications to the schema. Having only one schema master per forest prevents any conflicts that would result if two or more domain controllers attempt to simultaneously update the schema.
The effect of the schema master being unavailable
Temporary loss of the schema master is not visible to network users or to network administrators unless they are trying to modify the schema or install an application that modifies the schema during installation. If the schema master is unavailable and you need to make a change to the schema, you can seize the role to a standby operations master.
Domain Naming Master
Introduction
When you add or remove a domain from a forest, the change is recorded in Active Directory.
Roles performed by the domain naming master
The domain naming master controls the addition or removal of domains in the forest. There is only one domain naming master per forest. When you add a new domain to the forest, only the domain controller that holds the domain naming master role can add the new domain. The domain naming master prevents multiple domains with the same domain name from joining the forest. When you use the Active Directory Installation wizard to create a child domain, it contacts the domain naming master and requests the addition or deletion.
The effect of the domain naming master being unavailable
Like the schema master, temporary loss of the domain naming master is not visible to network users or to network administrators unless the administrator is trying to add a domain to the forest or remove a domain from the forest. If the domain naming master is unavailable, you cannot add or remove domains. If the domain naming master will be unavailable for an unacceptable length of time, you can seize the role from the standby operations master. To seize a role is to move it without the cooperation of its current owner. It is best to avoid seizing roles.
PDC Emulator
Introduction
The PDC emulator acts as a Microsoft® Windows NT® Primary Domain Controller (PDC) to support any backup domain controllers (BDCs) running Windows NT in a mixed-mode domain. When you create a domain, the PDC emulator role is assigned to the first domain controller in the new domain.
Roles performed by the PDC emulator
The PDC emulator performs the following roles:
- Acts as the PDC for any existing BDCs. If a domain contains any BDCs or client computers that are running Windows NT 4.0 and earlier, the PDC emulator functions as a Windows NT PDC. The PDC emulator services client computers and replicates directory changes to any BDCs running Windows NT.
- Manages password changes from computers running Windows NT, Microsoft Windows® 95 or Windows 98. You must write password changes directly to the PDC.
- Minimizes replication latency for password changes. Replication latency is the time needed for a change made on one domain controller to be received by another domain controller. When the password of a client computer running Windows 2000 or later is changed on a domain controller, that domain controller immediately forwards the change to the PDC emulator. If a password was recently changed, that change takes time to replicate to every domain controller in the domain. If a logon authentication fails at another domain controller because of a bad password, that domain controller will forward the authentication request to the PDC emulator before rejecting the logon attempt.
RID Master
The relative identifier (RID) master allocates blocks of RIDs to each domain controller in the domain. Whenever a domain controller creates a new security principal, such as a user, group, or computer object, it assigns the object a unique security identifier (SID). This SID consists of a domain SID, which is the same for all security principals created in the domain, and a RID, which is unique for each security principal created in the domain.
How the RID master supports creating and moving objects
The RID master supports creating and moving objects as follows:
1. Creating objects. To allow a multimaster operation to create objects on any domain, the RID master allocates a block of RIDs to a domain controller. When a domain controller needs an additional block of RIDs, it contacts the RID master, which allocates a new block of RIDs to the domain controller, which in turn assigns them to the new objects. If a domain controller.s RID pool is empty, and the RID master is
unavailable, you cannot create new security principals on that domain controller. You can view the RID pool allocation by using the Domain Controller Diagnostic (dcdiag) utility. You can install the dcdiag utility by installing the support tools, which are located in the \Support\Tools on the product CD.
2. Moving objects. When you move an object between domains, the move is initiated on the RID master that contains the object. This way, there is no duplication of objects. If an object were moved, but no single master kept this information, you could move the object to multiple domains without realizing that a previous move had already occurred. The RID master deletes the object from the domain when the object is moved from that domain to another domain.
Infrastructure Master
The infrastructure master is a domain controller that is responsible for updating object references in its domain that point to objects in another domain. The object reference contains the object.s globally unique identifier (GUID), distinguished name, and possibly a SID. Active Directory periodically updates the distinguished name and SID to reflect changes made to the actual object, such as moves within and between domains and the deletion of the object. If SID or distinguished name modifications to user accounts and groups are made in other domains, the group membership for a group on your domain that references the changed user or group needs to be updated. The infrastructure master for the domain in which the group (or reference) resides is responsible for this update; it distributes the update through normal replication throughout its domain. The infrastructure master updates object identification according to the following rules:
- If the object moves at all, its distinguished name will change because the distinguished name represents its exact location in the directory.
- If the object is moved within the domain, its SID remains the same.
- If the object is moved to another domain, the SID changes to incorporate the new domain SID.
- The GUID does not change regardless of location because the GUID is unique across domains.
Infrastructure master and the global catalog
The infrastructure master should not be the same domain controller that hosts the global catalog. If the infrastructure master and the global catalog are on the same computer, the infrastructure master does not function because it does not contain any references to objects that it does not hold. In addition, the domain replica data and the global catalog server data cannot exist on the same domain controller.
Periodically, the infrastructure master for a domain examines the references in its replica of the directory data to objects that are not held on that domain controller. It queries a global catalog server for current information about the distinguished name and SID of each referenced object. If this information has
changed, the infrastructure master makes the change in its local replica. These changes are replicated by using normal replication to the other domain controllers within the domain.
Transferring and Seizing Operations Master Roles
Introduction
When you create a Microsoft® Windows® Server 2003 domain, Windows Server 2003 automatically configures all of the operations master roles. However, you may need to reassign an operations master role to another domain controller in the forest or the domain. To reassign an operations master role, determine the holder of the operations master role and then either transfer or seize the operations master role.
Transfer of Operations Master Roles
The placement of operations master roles in a forest is done when the forest and domain structure is implemented, and requires change only when making a major change to the domain infrastructure. Such changes include decommissioning a domain controller that holds a role or adding a new domain controller that is better suited to hold a specific role. Transferring an operations master role means moving it from one functioning domain controller to another. To transfer roles, both domain controllers must be up and running and connected to the network. No data loss occurs when you transfer an operations master role. The process of role transfer involves replicating the current operations master directory to the new domain controller, which ensures that the new operations master has the most current information available. This transfer uses the normal directory replication mechanism.
Procedure for transferring RID master, PDC emulator, and Infrastructure
master role
To transfer the operations master role for the RID master, PDC emulator, or
infrastructure master, perform the following steps:
1. Open Active Directory Users and Computers.
2. In the console tree, right-click Active Directory Users and Computers,
and then click Connect to Domain Controller.
3. In the Or select and available domain controller list, click the domain
controller that will become the new operations master, and then click OK.
4. In the console tree, right-click the domain that contains the server that will
become the new operations master, and then click Operations Masters.
On the Infrastructure, PDC, or RID tab, click Change.
Procedure for transferring the domain naming master role
To transfer the domain naming master role to another domain controller,
perform the following steps:
1. Open Active Directory Domains and Trusts.
2. In the console tree, right-click Active Directory Domains and Trusts, and
then click Connect to Domain Controller.
3. In the Or select and available domain controller list, click the domain
controller that will become the new domain naming master, and then click
OK.
4. In the console tree, right-click Active Directory Domains and Trusts, and
then click Operations Master.
5. When the name of the domain controller that you selected appears, click
Change, and then click Yes.
Procedure for transferring the schema master role
To transfer the schema operations master role, perform the following steps:
1. Open Active Directory Schema.
2. In the console tree, right-click Active Directory Schema, and then click
Change Domain Controller.
3. Click Specify Name, type the name of the domain controller that you want
to transfer the schema master role to, and then click OK.
4. In the console tree, right-click Active Directory Schema, and then click
Operations Master.
5. When the name of the domain controller that you selected appears, click
Change, and then click Yes
When to Seize Operations Master Roles ?
Introduction
Seizing an operations master role means forcing an operations master role on another domain controller that cannot contact the failed domain controller and perform a transfer.
Implications of seizing a role
Seizing an operations master role is a drastic step. Do it only if the current operations master will never be available again and if a role cannot be transferred. Because the previous role holder is unavailable during a seizure, you cannot reconfigure or inform it that another domain controller now hosts
the operations master role. To reduce risk, perform a role seizure only if the missing operations master role unacceptably affects performance of the directory. Calculate the effect by comparing the impact of the missing service to the amount of work that is needed to bring the previous role holder safely back online after you perform the role seizure. Before you seize a role, you must permanently disconnect the
domain controller that holds the operations master role from the network. If the previous role holder comes back online after you seize an operations master role, it waits until after a full replication cycle before resuming the role of operations master. This way, it can see if another operations master exists
before it comes back online. If it detects one, it reconfigures itself to no longer host the roles in question.
Procedure for seizing a role by using Active Directory Users and Computers
To seize an operations master role for the PDC emulator or infrastructure master, perform the following steps:
- Open Active Directory Users and Computers.
- In the console tree, right-click the domain for which you want seize an operations master, and then click Operations Masters. It may take several seconds for the data to appear because Active Directory Users and Computers is waiting for a response from the current holder of the operations master role. Because the current role holder has failed and cannot respond, the last updated information appears.
- In the Operations Master dialog box, on the tab of the operations master role that you want to seize, click Change.
- In the Active Directory dialog box, click Yes.
- When an Active Directory dialog box appears indicating that this computer is a non-replication partner, click Yes.
- When an Active Directory dialog box appears indicating a transfer is not possible, click Yes.
- In the Active Directory dialog box, click OK, and then click Close.
- Close Active Directory Users and Computers.
Procedure for seizing a role by using Ntdsutil
To use the ntdsutil command to seize an operations master role, perform the
following steps:
1. In the Run box, type cmd and then click OK.
2. At the command prompt, type ntdsutil
3. At the ntdsutil prompt, type roles
4. At the fsmo maintenance prompt, type connections
5. At the server connections prompt, type connect to server followed by the fully qualified domain name
(FQDN) of the domain controller that will be the new role holder, and then type quit
6. At the fsmo maintenance prompt, type one of the following commands to seize the appropriate
operations master, and then type quit
• Seize RID master
• Seize PDC
• Seize infrastructure master
• Seize domain naming master
• Seize schema master
7. At the ntdsutil prompt, type quit
8. Verify the new holder of the operations master role that you seized.
How to Determine the Holder of an Operations Master Role ?
Introduction
Before you consider moving an operations master role, determine which domain controller holds a particular operations master role. Authenticated users have the permission to determine where the operations master roles are located. Depending on the operations master role, use one of the following Active Directory consoles:
- Active Directory Users and Computers (PDC, RID, infrastructure)
- Active Directory Domains and Trusts (Domain Naming)
- Active Directory Schema (Schema)
1. Procedure to determine RID master, PDC emulator, and infrastructure master
To determine which domain controller holds the RID master, PDC emulator, or
infrastructure master roles, perform the following steps.
1. Open Active Directory Users and Computers.
2. In the console tree, right-click the domain for which you want to view
operations masters, and then click Operations Masters.
3. On the RID, PDC, or Infrastructure tabs, view the names of the current
operations master under Operations master.
2. Procedure for determining the domain naming master
To determine which domain controller holds the domain naming master role,
perform the following steps:
1. Open Active Directory Domains and Trusts.
2. Right-click Active Directory Domains and Trusts, and then click Operations Master.
3. In the Change Operations Master dialog box, view the name of the current
domain naming master.
3. Procedure for determining the schema master
To determine which domain controller holds the schema master role, perform
the following steps:
1. Register the Active Directory Schema snap-in by running the following command:
regsvr32.exe %systemroot%\system32\schmmgmt.dll
2. Click OK to close the message that indicates the registration succeeded.
3. Create a custom Microsoft Management Console (MMC) console, and then
add the Active Directory Schema snap-in to the console.
4. In the console tree, expand and right-click Active Directory Schema, and
then click Operations Master.
5. In the Change Schema Master dialog box view the name of the current schema master.
1) What is the difference between UNIX and windows operating systems?
Ans. UNIX supports multithreading where as windows does not support multithreading. UNIX is an operating system which supports multithreading.
The question u got is what is an threading - threading is nothing but like a process but it is more faster than a process.
The threads are more efficient than the process because it share memory instead of system call.
Here u may get a doubt that what is a system call.
A system call is invoked as a mediator between a process and operating system.
Threading flows in a sequential process.
In threading we have single threading and multiple threading.
The best example i can give u is as we know that in UNIX many users share memory but they may not know that they are sharing.
Here if a user have multi threading (that is he is using the Unix)he need to complete a task i.e. a spread sheet consist of different calculations.
if one row is changed entire complete spread sheet should be changed.
So here for every task one thread is allotted so the task is completed more faster than a system call.
2) Describe four general strategies for dealing with deadlock.
Ans.
the
four techniques are- 1) mutual
exclusion. 2) Circular wait. 3) Hold & wait
4) no preemption
3) OS Beep Sounds.
Ans.
single
beep stands for error in Refreshing
Double Beep stands for error in
memory
Continuous beep sound tells stands for RAM not working or RAM properly
not inserted in slot
4) What is the structure of file system? At the time when we create a partition how the blocks are allocated.
Ans.
At
the time of buying the hard-disk you will have full 80 GB. but after you format
it, you will see that the size is reduced to 78 GB or so. That is bcoz the
entire hard disk is divided in to several sectors and each sector is classified
as "Data section" and "Address section". This address section constitutes some
bytes and hence al together you may lose some 1 or 2GB.
The OS or the file
systems of OS are responsible for these address translations.
The device
driver translates the  block address to physical address [track, sector
etc.,]
Thus the file system would set up several tables for denoting the
free sectors, for denoting the sectors for a particular user etc.
5) What is the difference between multi programming operating system and multiprocessing operating system?
|
Ans. A multi processing os supports multiple processes to run with the help of some scheduling algorithm(round robin) its mean u can run multiple process at same time, there are two type of multi processing os 1) multiprocessing :- single Processor and multiple process2) symmetric multiprocessing :- multiple Processor and single processor a multiprogramming OS supports all features like 1) Multi tasking 2) Multi processing3} Multi threading( thread can also be considered as a task)but if any of these feature is not supported by the os then that os cant be multiprogramming os. |
6) Execution of program? Can we execute a program with out installing Operating system? If yes, how it can be done?
Ans. Yes. using EPROM.
7) If the OS is just a collection pf programs and if it is executed by the processor just like any other program, is the OS a process? If so, how is it controlled?
Ans.
Execution
contexts can be of two types: thread/process context OR an Interrupt context.
What this means is that to execute code, one has to be in a thread context or a
an Interrupt context. OS code or any code for that matter has no context. It is
the execution stream that has a context. So, whenever we are executing OS code,
we are doing so on behalf of one of the two contexts mentioned above.
The
behavior of the OS is controlled by user requests via system calls, by interrupt
requests and by the policy and mechanisms put in place to manage resources,
provide protection, etc.
8) Explain the Windows XP, 2000 and 2003 Boot Process?
Ans. following
are the booting files for xp
boot.ini, ntldt, ntdetect.com, ntoskrnl.exe,
bootdd.sys, bootsect.dos,hal.dll, system.
First there will be pre- boot
sequence, it includes the following
1.POST(power on self test) first
check for hardware
2.loads boot.ini, loads mbr.
3.mbr loads active
partation
4ntldr loads o.s.
boot process: first loads boot.ini, ntldr will be in boot.ini it loads os. boot.ini shows available os for selection, ntdetect.com check for hardware, ntoskrnl.exe loads drivers for devices.
9) What is DHCP, How it Works?
Ans. DHCP stands for dynamic host configuration protocol. What it does is dynamically assign network settings from a server. Hence a DHCP configured PC boots; it requests its IP address from the DHCP server. It does this by sending a standardized DHCP broadcast request packet to the DHCP server with a source IP address of 255.255.255.255. If your DHCP server has more than one interface, you have to add a route for this 255.255.255.255 address so that it knows the interface on which to send the reply; if not, it sends it to the default gateway. (In both of the next two examples, we assume that DHCP requests will be coming in on interface eth0).
10) What do you mean by fault tolerance?
Ans. Fault tolerance is a concept in kernel. There are basically two types of kernel
[1] Monolithic kernel [used in windows XP or generally]
[2] Microkernel [used in robotics]
Monolithic kernel has hierarchical protection domain. That means its hardware management is in ring form. In monolithic kernel there is single memory and all applications are using same memory with frequent & good access of system resources. There resources are linked with h/w. So even a single fault to hardware can corrupt the whole system.
So in safety of this micro kernel designed so that even single faults of h/w do not corrupt whole system.
11) Difference between NTFS and FAT32?
Ans. NTFS
1) Allows access local to w2k, w2k3, XP, win NT4 with SP4 & later may get access for some file.
2) Maximum size of partition is 2 Terabytes & more.
3) Maximum File size is up to 16TB.
4) File & folder Encryption is possible only in NTFS.
FAT 32
1) Fat 32 Allows access to win 95, 98, win millenium, win2k, xp on local partition.
2) Maximum size of partition is up to 2 TB.
3) Maximum File size is up to 4 GB.
4) File & folder Encryption is not possible.
FAT (FAT16 and FAT32) and NTFS are two methods for storing data on a hard drive. The hard drive has to either be formatted using one or the other, or can be converted from one to the other (usually FAT to NTFS) using a system tool.
NTFS is a high-performance and self-healing file system proprietary to Windows XP 2000 NT, which supports file-level security, compression and auditing. It also supports large volumes and powerful storage solution such as RAID.
The most important new feature of NTFS is the ability to encrypt files and folders to protect your sensitive data
12) What will happen if you have a set of interrupt signals arrived at the same time?
Ans.
There
are some scheduling algorithms to control the multiple
interrupts so many os mostly used priority based algorithm in this
each process allotted with their priorities in that time they will
execute.
If not used any algorithms tat may lead to deadlock
state.
13) What is virtual machine?
Ans- A self-contained operating environment that behaves as if it is a separate computer.
14) Difference between a process and a program ?
Ans. Please do not confuse process with program. Program is only a set of instructions and process is a program in memory. Thread is a basic unit of execution within a process. This means program is something which is not loaded in memory yet. And Process is loaded in memory but not a complete execution unit. We say only a thread is under execution. I would request some of my friends, please refer somewhere thoroughly before sending misleading answers.
15) Discuss the advantages and disadvantages of removing operating system altogether?
Ans.
Advantages
We can use hardware more efficiently, we get efficient results.
Disadvantages
Memory loss, dead locks, pre-emptions, so on...
16) Can we do
thread scheduling? If yes, How do we use?
How to know the priority of
thread?
Ans. If it is about scheduling processes nice value comes into picture but when you are talking about threads (LWP) nice value cannot be used. There are APIs to set the thread priorities A to affect scheduling.
17) What is the difference between THREAD, PROCESS and TASK?
Ans.
Thread:
Thread is separate path of execution which R functionally independent of each
other.
Process: A program in execution is called process.
Task: In
program contains tasks. Each task is nothing but job.
18) What is the difference between the socket and pipe?
Ans. socket and Pipe are all together different thinks
Socket -It is part of OSI LAYER MODEL. in Osi model communication between different layer takes places through sockets. say application layer provide services trough certain sockets to presentation layer and presentation layer uses certain other socket to communicate with upper application layer.
Socket are used in SECURE SOCKET LAYER NETWORKS
Pipes- it is related to processing of a process in
cpu , pipes are segments of a process in execution.
generally process are divided into distinct segments which are linearly dependent i. e output of first segment become input for next segment and so on
generally by processing multiple pipes simultaneously ,we can improve productivity i. e we can run different pipe segment simultaneously, by keeping in mind ,that they don’t indulge in waiting for each other.
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19) What is the difference between safe mode and normal mode. Difference between 32 bit and 64 bit operating systems?
Ans. In normal mode all drivers are accessed and given access. Where as in Safe mode only selected drivers are accessed.
A bit is binary information. It is either 0 (off) or 1 (on). A 64-bit operating system can move 64 bits of data per clock cycle (1 GHz+ moves billions per second). Going from a 16-bit OS (Windows 3.1) to 32-bit (Windows XP) will make a huge difference on the same machine.
A
64-bit OS is better than 32-bit because:
- It
effectively doubles system capabilities if the system is running a 64-bit
processor.
- More information can be
sent at one time on a 64-bit system than on a 32-bit system. It's great for
data-intensive programs.
- You can run
a 32-bit app on a 64-bit operating system, much like you can run a 16-bit app on
Windows XP.
-
Microsoft is enabling developers to build 64-bit functionality within its 32-bit
programs.
20) What is exchange server?
Ans. Exchange server is a Microsoft product, it is used for mail server with Microsoft server, it uses AD, Users and other server facility.
21Can we load Linux OS in micro controller/ ARM processor? if yes then HOW?
Ans. No.
22. Give tabular difference between batch processing, time sharing, online time sharing, and multiprogramming batch system and distributed operating systems?
Ans.
Batch
Processing:In batch processing Operating systems the tasks are performed in
batches,os waits for a batch of tasks to arrive and performs the operation on
the batch.
Time Sharing: in time sharing operating systems the
operating systems shares the time between the tasks, i.e. if job A
takes 6 minutes to complete and the predefined time to the os is 2
min it first performs the first job A for 2 minutes, then
takes up job B(the next one) and this way shares its time between all the
jobs arriving.
Online Timesharing: online time sharing operating
system has the same function of the time sharing operating system
except that the jobs are given time in the order they come.
Multi programming: In multiprogramming batch operating
systems the multiplle jobs are performed by the operating
system simultaneously at a time.
Distributed Operating
systems: in distributed operating systems, different processors that are loosely
coupled operate on different jobs and communicate with each other.
23. What are the Different types of backup?
Ans. When you backup files, means that you make a safe copy of the file. So when the original data is corrupted , and if there is a backup of that original data, we can retrieve that original information.Kool right, so therz no loss of data. Thats why its been used in almost all the organizations.
Backup devices are:
Floppy drives, LS-120 drives, ZIP drives & Jaz drives.
Normal—Backs up the files you select, and marks the files as backed up.
Incremental—Backs up the files that changed since the last backup, and marks the files as backed up.
Differential—Backs up the files that changed since the last backup, but doesn’t mark the files as backed up.
Copy—Backs up the files you select, but doesn’t mark the files as backed up.
Daily—Backs up the files that changed that day, but doesn’t mark the files as backed up.
24. What is the shortest definition of os?
Ans. OS is a Interface between a user and the hardware of a computer.
25. Why paging? What is virtual memory? what is virtual address space?
Ans. Paging is a memory management technique used by operating system.
in it complete memory is divided into logical blocks of equal size. whenever any page is required o/s search for that page in memory, if it don’t find than a trap is generated known as Page fault and this new page get loaded in RAM from secondary memory.
virtual memory is also memory management technique generally deployed when
a computer is not having enough(large)RAM for a large program to be kept in memory, but as we know for fast and successful execution of program ,it is required to be present in memory and our problem is of less RAM
thus virtual memory provide solution to this problem
virtual memory provides mapping technique for Mapping program generated RAM address to actual physical address of secondary Memory, at run time .it proved illusion as if our RAM is large enough to hold complete program.
it is generally used in graphic oriented programs and applications.
26. What is special in SP2 for windows xp?
Ans.
With
Windows XP Service Pack 2 (SP2), Microsoft is introducing a set of security
technologies that will help improve Windows XP-based computers' ability to
withstand malicious attacks from viruses and worms. These technologies
include:
Network protection ,Memory protection, Improved email security,
Safer browsing.
ICF internet connection firewall, Enhanced HCL support, Improved wireless support, Bluetooth enabled, Windows media player 9, Internet explorer popup blocker, firewall protection from startup to shutdown.
27. Difference between win98 and windows XP?
Ans. Win98
1. Win98 Support FAT file system & XP support NTFS and Also FAT.
2. Win98 Does not having Remote Access facility While in XP there is.
3. Win98 Does not need faster processing speed while XP Need 500MHz processing Speed.
4. Win98 Does not provide System Restore while XP Provide.
5. Win98 does not having Hibernate facility While XP having Hibernate Facility.
6. Win98 and WinXp layout and visual Styles are Different.
7. WinXp improves Device Support.
8. WinXp having CD Burning Facility, fast user Switching.
9. Ability to support multithreading to utilize hyper threading feature.
28. Difference between Pentium 3 and Pentium 4?
Ans. The processor frequency up to 1.2 GHz 12.10X is P3
The processor frequency greater than 1.2 GHz is P4
The Cache memory in P4 is increased compared to P3
In P4 We have a special range of processor with HT technology and Dual core.
29. What would system restore do? Technically what would it do?
Ans. Its is a kind backup utility, which help when the O/s gets corrupted or we lose our setting of O/s
Always this should be enabled in windows so that we can restore the latest settings when we face any problems
30. Difference between time sharing and multitasking systems?
Ans. Time Sharing: programs are executed in an interleaved manner that is 1st the programs are merged together to form a single stream of instruction then given to the processes for execution.
Multitasking: programs are kept separate and cpu switches in between the different processes and execute there instruction separately. no interleaving concept is there.
31. In single networking which addressing is used to send data ? logical or physical addressing?
Ans. logical address which is used is 127.0.0.1. This is a loop back address. If you send some data to this address then it comes back to you.
32. What is Hyper Threading? Tell me about Windows Vista?
Ans. Hyper threading is Intel’s version of a Multithreading. It duplicates the front end of the processor Core attempting to schedule / Guess where it can put threads to better utilize a semi idle processor. The Intel Implementation was heavily flawed and suffered from Bad branch prediction. On most server implementations it is advisable to turn Hyper threading off. Also in processor intensive games, Battlefield 2 ... Hyper threading causes frame lag. If you turn Hyper threading off you get better FPS.
33. What is the meaning of physical memory and virtual memory?
Ans. Physical memory is the amount of random access memory (RAM) in your computer.
Virtual memory is hard disk space reserved to emulate physical memory. Virtual memory is also called swap space.
34. What is the difference between general purpose operating system and Real time operating system?
Ans. General Purpose operating system is never time bound. no time limit is specified for completing a process. But a real time system, a time limit is specified for each process to finish. Real systems are of 2 types: soft time real systems and hard time real systems. In soft time real systems, if the process is completed in specified time the the process is accepted and if it is not, then the quality of the process is degraded. In hard time real systems, if the process is completed in the specified time limit, then it is accepted and if not, then the process is simply discarded.
35. What is the Hibernation Mode?
Ans. Hibernation mode is used to conserve batteries or power. When you turn computer into this mode all the application in the memory are saved on hard disk and computer shuts down. On switching on it resumes where it left out and this resume operation is quicker than switching on from normal shut down.
36. Distinguish between the operation of single and multi user operating systems?
Ans. operation of multi user operating systems are having the functions like time sharing and data sharing while this is not done in single user operating system.
37. What do you understand by MOM?
Ans.
MOM
stands for Microsoft Operations Manager. It is an application used for
monitoring health of servers. MOM can monitor lot of things in a server. Such as
event viewer entries, performance counters etc. For example. MOM can be
configured to watch for a specific performance counter in a server and send an
alert when the specific counters crosses a threshold. The alert is normally
delivered to MOM operator's console. Configuration is done through MOM admin
console.
New version of MOM is called SCOM (System Center Operations
Manager).
Custom scripts & tasks can be written using VBScript,
JScript etc.
38. What is meant by HT in P-IV HT system?
Ans. This technology states that it can accept multiple thread at one shot which it not possible in normal P4 structure, so the speed increase in HT Processor.
39. What is RAS Server? Mention its Uses?
Ans. RAS (Remote Authentication Server). It is mainly used to authenticate the user logging into the network through internet example VPN.
40.
The process of transforming one bit pattern into
another by bit-wise
operations is called
1. Masking 2. Pruning
3. Biting 4.
Chopping
Ans.
It
is called masking.
In masking you select a bit pattern and do bit wise OR or
AND operation to set a particular bit of a no.
e.g. in a 4 bit no, you
have to set the LSB to be 1 always. Then you take mask as 0001 and do OR
operation
x|0001
if the bit is set to be 0 always then mask =
1110 and do AND operation
x&1110
41. What is the difference between blocking and waiting state of process?
Ans.
A
blocking state is the state in which the process is waiting for some operation
to get completed. It can be an I/O operation or some
Inter-Process-communication. The process can not execute further without these
signals.
A waiting state is the state in which the process is ready to run
but the processor is not idle.
When the operation on the blocked process
complete, it will move in to the waiting state.
42. What is distributed Systems?
Ans. Distributed system in general refers to n/w o.s in which various systems (computers) are connected to sharing some of resources like printer etc. Each system have own data (including files etc) and whenever access over other's system data is required FTP (file transfer protocol) is used. One must have login and password to access remote files. Some systems also support anonymous FTP.
43. Why thread is called as a lightweight process?
Ans.
thread
is a lightweight process because it simply divides a process into various sub
processes....each sub process completes specific task and these threads run
simultaneously (parallel) resulting in speedy process completion & reduced
resource usage. Hence less load on O.S.
44. What resources are used when a thread created? How do they differ from those when a process is created?
Ans.
Thread:
In case of thread only one copy of resources are made.
means Resources are shared between different threads. This is done on a
synchronized basis.
Process:
A separate instances of
resources are allotted to different processes at same time and they are not
synchronized.
45. Define Demand Paging, Page fault interrupt, and Trashing?
Ans. Demand Paging: Demand paging is the paging policy that a page is not read into memory until it is requested, that is, until there is a page fault on the page.
Page fault interrupt: A page fault interrupt occurs when a memory reference is made to a page that is not in memory.
The present bit in the page table entry will be found to be off by the virtual memory hardware and it will signal an interrupt.
Trashing: The problem of many page faults occurring in a short time, called “page thrashing,”
46. What do you mean by deadlock?
Ans. Deadlock is a situation where a group of processes are all blocked and none of them can become unblocked until one of the other becomes unblocked.
The simplest deadlock is two processes each of which is waiting for a message from the other.
47. Give an example of microkernel?
And. WinNT, Minx
48. What is DRAM? In which form does it store data?
Ans. DRAM forms the Physical Memory of the PC. The process of recharging described in the earlier post is known as a Refreshing Cycle.
49. How chkdsk command works?
Ans. Check disk is a command in DOS and Microsoft Windows systems which verifies a hard disk or a floppy disk for file system integrity. It is similar to the fsck command in Unix. By default, CHKDSK neither fixes errors nor checks for bad sectors. In order to fix errors while using the command line interface, the /F parameter should be specified. In order to check for and mark bad sectors, the /R parameter should be specified. Other parameters can be listed by typing the command chkdsk /?
50. What are the basic functions of an operating system?
Ans. Operating system controls and coordinates the use of the hardware among the various applications programs for various uses. Operating system acts as resource allocator and manager. Since there are many possibly conflicting requests for resources the operating system must decide which requests are allocated resources to operating the computer system efficiently and fairly. Also operating system is control program which controls the user programs to prevent errors and improper use of the computer. It is especially concerned with the operation and control of I/O devices.
51. Difference between Logical and Physical Address Space?
Ans. The concept of a logical address space that is bound to a separate physical address space is central to proper memory management.
Logical address – generated by the CPU; also referred to as virtual address.
Physical address – address seen by the memory unit.
->Logical and physical addresses are the same in compile-time and load-time address-binding schemes; logical (virtual) and physical addresses differ in execution-time address-binding scheme
52. what is page fault?
Ans. Page fault is the situation when the CPU want to access a page from the cache but it doesn't find there. So it has to go to the main memory for the particular page. This is Page fault.
53. Root Directory.
Ans.
The
root directory of disk should be placed
1. at a fixed address in main
memory
2. at a fixed location on disk
3. anywhere on the disk
4. at a
fixed location on the system disk
54. Which file extension is responsible for holding address book in outlook express?
Ans. Outlook Express is a no-cost, basic e-mail program that is included with Microsoft Internet Explorer. Outlook Express stores contacts in a Microsoft Windows® Address Book file with an extension of .wab. The name of the file is based on your Windows logon name. For example, Lori Kane may have a Windows logon name of lorik, and her Windows Address Book file would be lorik.wab. This file is saved at C:\Documents and Settings\<user name>\Application Data\Microsoft\Address Book. -Referene: Microsoft Office Online.
55. What is the difference between outlook exp and ms outlook?
Ans. In Outlook express only support up to POP3 and SMTP protocol for mail, Outlook Express is single user based mail client, whereas MS-Outlook can be used as multi-user mail client application.
In MS-Outlook Express support IMP And IMP4 mail protocol, its store large database, more secure support all format mail like Richtext, HTML, word editing, Spell Check, Ms-outlook has several other features also to manage our daily routing work in office, for example diary, reminders, etc.
Outlook exp did not support as exchange client, but ms outlook support as exchange client.
56. What are the main difference between Micro-Controller and Micro- Processor?
Ans. A microcontroller is by definition a is a computer on a chip. It includes all the necessary parts (including the memory) all in one IC. You just need to apply the power (and possibly clock signal) to that device and it starts executing the program programmed to it. A microcontroller generally has the main CPU core, ROM/EPROM/EEPROM/FLASH, RAM and some necessary functions (like timers and I/O controllers) all integrated into one chip. The original idea behind the microcontroller was to limit the capabilities of the CPU itself, allowing a complete computer (memory, I/O, interrupts, etc) to fit on the available silicon real estate.
Microcontrollers are typically used where processing power isn't so important. More important are generally compact construction, small size, low power consumption and that those chips are cheap. For example controlling a microwave oven is easily accomplished with the smallest of microcontrollers. There is countless number of small electronic devices which are nowadays based on microcontroller. A modern home can include easily tens or hundreds of microcontrollers, as almost every modern device which has electronics have a microcontroller (or more than one) inside.
Microprocessor is generally just the CPU core itself, although nowadays it might have some accessory parts also integrated to the same chip
57. I have deleted a file from recycle bin but i want to use that file how can i restore that file? I have already used system restore for the same but the file couldn't be restored?
Ans. Use RDstudio, it will recover all the files one had deleted. There is two solutions:
1. Restore from last back.
2. User Recycler folder. Start-->RUN-->type c:recycler --> type FTYPE
58. Differentiate between RAM and ROM?
Ans. Semiconductor memories are of two types: RAM (random access memory) and ROM (read only memory).
RAM is a read/write memory. Information can be written into and read from a RAM. It is volatile memory.
It stores information so long as power supply is on.
ROM is permanent type memory. Its contents are not lost when power supply goes off. the user cannot write into a ROM.Its contents are decided by the manufacturer and written at the time of manufacture.
Programmable ROMs are also available. They are called PROMs.
59. Difference between TCP and RDP, DOMAIN and OU. DOMAIN CONTROLLER and GLOBAL CATALOG?
Ans. 1.Transmission Control Protocol: a standard protocol for transmitting the information.
Remote Desktop Protocol: Used for accessing the Desktop Remotely
2.Domain: A security boundary for the network
Organizational Unit: A part of Active Directory used to Organise and Manage the objects of AD
3.Domain Controller: Used for managing the objects in the domain
Global Catalog Server: A Domain Controller promoted to be a CG, holds partial replica of every object in the forest.
60. What is use of ntbootdd.sys file?
Ans. this file is used when you have a scsi drive, basically this file stores the scsi driver if it is not available with windows os.
61. What is difference between Global catalog and infrastructure master?
Ans. 1. GC holds group membership of universal group. while Infrastructure hold group information in domain level. Global Catalog server holds a partial replica of every object in the forest. Global Catalog server holds a partial replica of every object in the forest.
2. We can't set infrastucture mastre and GC together on same DC. Infrastructure Master contains the references to objects in the forest.
62. What is the main component of operating system?
Ans. main component of operating system are kernel and shell
Shell is a interface between application program and kernel whenever application program wants some work to be done It contacts kernel and kernel in turn perform work with the help of device drivers .thus we can say
Kernel is an interface between hardware and shell.
Kernel uses device drivers to control microcontroller card of peripheral device and in turn work is being accomplished.
Application program -> [shells ->kernel ->device driver -> controller card -> physical hardware]
63. What are the major differences between windows XP and Windows 2000 operating systems?
Ans. major differences between win2000 Professional and WinXp Professional that are: 1.REMOTE DESKTOP: we can remotely connect WinXp machine from any windows system like win98, win2000, winxp and win2003 2.SHARING NETWORK CONNECTION: we can share easily our network resources to other people those r resided in other network. {Whereas in win2000, we can share our internet connection to our local network only.} 3. FIREWALL: we can restrict deny the people in the internet who r trying to access our resources and wanton corrupt our systems like Hackers. 4. SOFTWARE RESTRICTIONS In Group Policy: we can restrict the particular users such that they cannot use particular software using group policies. 5. Past switching user login: multiple users can login with ought logging off already login user; with ought losing any data in the same WinXp machine. 6. Version Confliction: we can install multiple versions of same application in one Machine. (Even we can install in win98, win2000, some where in the middle, we face the problem.)
64. Why do multi-tasking operating systems in a single user machines today?
Ans. The need for multi-tasking operating systems including Unix, Linux, Windows xp , 2000 etc. in a single user machines is for simultaneous access to many applications. For example while using internet explorer wants attach some document file(.doc) it is not updated then he needs to open the Ms-Word, edit it and save it then attach it and simultaneously he can open the pdf file with acrobat reader for referring some digitized book etc. And can search for some information with google it is possible only because of multi-tasking operating systems.
65. Different types of Real-Time Scheduling?
Ans. Hard real-time systems – required to complete a critical task within a guaranteed amount of time.
Soft real-time computing – requires that critical processes receive priority over less fortunate ones.
I think Hard Real time and Soft Real time is type of real time system.
But Question is Scheduling type.
I think scheduling types are:
a. Primitive priority based scheduling
B. Non-Primitive scheduling
C. Round Robin scheduling
66. What are Dump terminals in UNIX?
Ans. In short dump terminals are the terminals which are connected with a centralized CPU and lack individual CPUs.
67. What is a Real-Time System?
Ans. A real time process is a process that must respond to the events within a certain time period. A real time operating system is an operating system that can run real time processes successfully
68. Describe different job scheduling in operating systems?
Ans. Scheduling is the activity of the deciding when process will receive the resources they request.
FCFS: --- FCSFS stands for First Come First Served. In FCFS the job that has been waiting the longest is served next.
Round Robin Scheduling: ---Round Robin scheduling is a scheduling method where each process gets a small quantity of time to run and then it is preempted and the next process gets to run. This is called time-sharing and gives the effect of all the processes running at the same time
Shortest Job First: -- The Shortest job First scheduling algorithm is a nonpreemptive scheduling algorithm that chooses the job that will execute the shortest amount of time.
Priority Scheduling: ---Priority scheduling is a scheduling method where at all times the highest priority process is assigned the resource.
69. What is hard disk and what is its purpose?
Ans. Hard disk is the secondary storage device, which holds the data in bulk, and it holds the data on the magnetic medium of the disk.Hard disks have a hard platter that holds the magnetic medium, the magnetic medium can be easily erased and rewritten, and a typical desktop machine will have a hard disk with a capacity of between 10 and 40 gigabytes. Data is stored onto the disk in the form of files.
70. What is cache memory?
Ans. Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. As the microprocessor processes data, it looks first in the cache memory and if it finds the data there (from a previous reading of data), it does not have to do the more time-consuming reading of data from larger memory.
71. Why paging is used?
Ans. Paging is solution to external fragmentation problem which is to permit the logical address space of a process to be noncontiguous, thus allowing a process to be allocating physical memory wherever the latter is available.
72. Difference between Primary storage and secondary storage?
Ans. Main memory: – only large storage media that the CPU can access directly.
Secondary storage: – extension of main memory that provides large nonvolatile storage capacity.
73. What is CPU Scheduler?
Ans. Selects from among the processes in memory that are ready to execute, and allocates the CPU to one of them.
->CPU scheduling decisions may take place when a process:
1. Switches from running to waiting state.
2. Switches from running to ready state.
3. Switches from waiting to ready.
4. Terminates.
->Scheduling under 1 and 4 is no preemptive.
->All other scheduling is preemptive
74. Recovery from Deadlock?
Ans. Process Termination:
->Abort all deadlocked processes.
->Abort one process at a time until the deadlock cycle is eliminated.
->In which order should we choose to abort?
Priority of the process.
How long process has computed, and how much longer to completion.
Resources the process has used.
Resources process needs to complete.
How many processes will need to be terminated?
Is process interactive or batch?
Resource Preemption:
->Selecting a victim – minimize cost.
->Rollback – return to some safe state, restart process for that state.
->Starvation – same process may always be picked as victim, include number of rollback in cost factor
75. What is Memory-Management Unit (MMU)?
Ans. ->Hardware device that maps virtual to physical address.
In MMU scheme, the value in the relocation register is added to every address generated by a user process at the time it is sent to memory.
->The user program deals with logical addresses; it never sees the real physical addresses.
76. What are Dynamic Loading, Dynamic Linking and Overlays?
Ans. Dynamic Loading:
->Routine is not loaded until it is called
->Better memory-space utilization; unused routine is never loaded.
->Useful when large amounts of code are needed to handle infrequently occurring cases.
->No special support from the operating system is required implemented through program design.
Dynamic Linking:
->Linking postponed until execution time.
->Small piece of code, stub, used to locate the appropriate memory-resident library routine.
->Stub replaces itself with the address of the routine, and executes the routine.
->Operating system needed to check if routine is in processes’ memory address.
->Dynamic linking is particularly useful for libraries.
Overlays:
->Keep in memory only those instructions and data that are needed at any given time.
->Needed when process is larger than amount of memory allocated to it.
->Implemented by user, no special support needed from operating system, programming design of overlay structure is complex
77. What are the different Dynamic Storage-Allocation methods?
Ans. How to satisfy a request of size n from a list of free holes?
First-fit: Allocate the first hole that is big enough.
Best-fit: Allocate the smallest hole that is big enough; must search entire list, unless ordered by size. It produces the smallest leftover hole.
Worst-fit: Allocate the largest hole; must also search entire list. Produces the largest leftover hole.
First-fit and best-fit are better than worst-fit in terms of speed and storage utilization.
78. What is fragmentation? Different types of fragmentation?
Ans. Fragmentation occurs in a dynamic memory allocation system when many of the free blocks are too small to satisfy any request.
External Fragmentation: External Fragmentation happens when a dynamic memory allocation algorithm allocates some memory and a small piece is left over that cannot be effectively used. If too much external fragmentation occurs, the amount of usable memory is drastically reduced.
Total memory space exists to satisfy a request, but it is not contiguous
Internal Fragmentation: Internal fragmentation is the space wasted inside of allocated memory blocks because of restriction on the allowed sizes of allocated blocks.
Allocated memory may be slightly larger than requested memory; this size difference is memory internal to a partition, but not being used
Reduce external fragmentation by compaction
->Shuffle memory contents to place all free memory together in one large block.
->Compaction is possible only if relocation is dynamic, and is done at execution time.
79. Under what circumstances do page faults occur? Describe the actions taken by the operating system when a page fault occurs?
Ans. A page fault occurs when an access to a page that has not been brought into main memory takes place. The operating system verifies the memory access, aborting the program if it is invalid. If it is valid, a free frame is located and I/O is requested to read the needed page into the free frame. Upon completion of I/O, the process table and page table are updated and the instruction is restarted.
80. What is the cause of thrashing? How does the system detect thrashing? Once it detects thrashing, what can the system do to eliminate this problem?
Ans. Thrashing is caused by under allocation of the minimum number of pages required by a process, forcing it to continuously page fault. The system can detect thrashing by evaluating the level of CPU utilization as compared to the level of multiprogramming. It can be eliminated by reducing the level of multiprogramming.
81. What is the difference between win 2000 ADS and win 2003 ADS?
ANS:- There are many features in windows 2003 domain controller as compares to
Windows 2000 DC like
1- We can create cross forest link trust.
2- Can rename domain name.
3- More scaleable
4- Have the features of ADAM (active directory application mode)
5- Support more processor compares to windows 2000
If you need more details contact me I can give you more stuff of Windows 2003,
Active directory, MS Exchange server.
82: What is the difference between windows server 2003 And 2000 Server ?
ANS:-
A) In 2000 we cannot rename domain whereas in 2003 we can rename Domain
B) In 2000 it supports of 8 processors and 64 GB RAM (In 2000 Advance Server) whereas in 2003 supports up to 64 processors and max of 512GB RAM
C)2000 Supports IIS 5.0 and 2003 Supports IIS6.0
D) 2000 doesn’t support Dot net whereas 2003 Supports Microsoft .NET 2.0
E) 2000 has Server and Advance Server editions whereas 2003 has Standard, Enterprise, Datacentre and Web server Editions.
F) 2000 doesn’t have any 64 bit server operating system whereas 2003 has 64 bit server operating systems (Windows Server 2003 X64 Std and Enterprise Edition)
G) 2000 has basic concept of DFS (Distributed File systems) with defined roots whereas 2003 has Enhanced DFS support with multiple roots.
H) In 2000 there is complexality in administering Complex networks whereas 2003 is easy administration in all & Complex networks
I) In 2000 we can create 1 million users and in 2003 we can create 1 billion users.
J) In 2003 we have concept of Volume shadow copy service which is used to create hard disk snap shot which is used in Disaster recovery and 2000 doesn’t have this service.
K) In 2000 we don’t have end user policy management, whereas in 2003 we have a End user policy management which is done in GPMC (Group policy management console).
L) In 2000 we have cross domain trust relation ship and 2003 we have Cross forest trust relationship.
M) 2000 Supports 4-node clustering and 2003 supports 8-node clustering.
N) 2003 has High HCL Support (Hardware Compatibility List) issued by Microsoft
O) Code name of 2000 is Win NT 5.0 and Code name of 2003 is Win NT 5.1
P) 2003 has service called ADFS (Active Directory Federation Services) which is used to communicate between branches with safe authentication.
Q) In 2003 their is improved storage management using service File Server Resource Manager (FSRM)
R) 2003 has service called Windows Share point Services (It is an integrated portfolio of collaboration and communication services designed to connect people, information, processes, and systems both within and beyond the organizational firewall.)
S) 2003 has Improved Print management compared to 2000 server
T) 2003 has telnet sessions available.
U) 2000 supports IPV4 whereas 2003 supports IPV4 and IPV6
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