How to manage MS cluster?

Question itself saying us to refer a whole cluster documentation. As per my knowledge

1. Ensure all the resources in a cluster should be online.

2. Frequently Perform a test by failing over and failback to make sure the cluster availability.

3. Go through the cluster log everyday to find if there are any errors or exceptions.

4. Keep in touch with storage admin to confirm the Backup/Raid of a cluster Shared disk and Quorum are going on fine.

5. Managing the cluster is depending on how you configure cluster resource dependencies. 

6. Think about the backup plan if in case major number of nodes failure. (Ofcouse the chance of failing all the nodes is less.

7. Make sure the heartbeat is working fine (Private Network). In case of NIC failure the resources keep on failing over and forth.

IIS Interview Questions and Answer

What is the Role of IIS ?

Visual studio having It own ASP.NET Engine which is capable enough to run Asp.net web application from visual studio. So we just click on Run button to start the application.
Now this is the scenarios of local environment. But If we want to host it on server from where all user can access the sites then IIS comes into the picture.

IIS provides a redesigned WWW architecture that can help you achieve better performance, reliability, scalability, and security for our Web sites. IIS can support following Protocol HTTP/HTTPS, FTP, FTPS, SMTP Etc. We need to host the site on IIS, when request comes from client it first hits the IIS Server, then the server passed it to ASP.NET worker process to execute. Then the response also passes to client via IIS itself.
Note only Hosting of Site we can create our FTP Server, SMTP Server using IIS itself.
There are different version of IIS available like 5.1, 6.0, 7.0 etc

What are the different version on IIS that you have worked on ?

Before answering this question you need to know what are the different IIS version is available in different OS. Below is the list of IIS version with different Operating system.
Windows Server 2008 - Windows Vista - Home Premium/ Ultimate - IIS 7.0
Windows Server 2003 - IIS 6.0
Windows XP Professional - IIS 5.1
Now based on your working experience you can say that you have worked on IIS 5.1 and 6.0 or only IIS 7. Etc.
Now, the next question that can asked after answering this question is “what is the difference between them ? ” – Well I will come with this later.

What is Application Pool in IIS ?

Before Giving the Definition : you can say like this, Concept of Application pool has from IIS 6.0 .
Application pools are used to separate sets of IIS worker processes that share the same configuration and application boundaries. Application pools used to isolate our web application for better security, reliability, and availability and performance and keep running with out impacting each other . The worker process serves as the process boundary that separates each application pool so that when one worker process or application is having an issue or recycles, other applications or worker processes are not affected.
One Application Pool can have multiple worker process Also.

Main Point to Remember:
1. Isolation of Different Web Application
2. Individual worker process for different web application
3. More reliably web application
4. Better Performance

What is the Name of Default Application Pool in IIS ?

Though we can create new application pool IIS with different settings, but IIS having its own default application pool named : DefaultAppPool

What are the different types of Identity available in IIS 6.0 ?

IIS having three different Identity.
1. Local System
2. Local Services
3. NetworkServices

Name of default Identity of IIS6.0

Default Identity of IIS 6.0 is NetworkServices .
Which is having very minimum rights on your system. The user can only have the read access of the site.

What is Recycling of Application Pool ?

ecycling Application pool means recycle the Worker process (w3wp.exe ) and the memory used for the web application.
There are two types of recycling related with Application pool

1. Recycling Worker Process - Predefined Settings
2. Recycling Worker Process - Based on Memory

What are the main layers of IIS Architecture ?

IIS having mainly two layer Kernel Mode and User Mode

Below are the subsection of both of them.
1. Kernel Mode
o HTTP.SYS
2. User Mode
o Web Admin Service
o Virtual Directory
o Application Pool

What is the Role of Http.Sys in IIS ?

HTTP.SYS is the kernel level components of IIS. All client request comes from client hit the HTTP.Sys of Kernel level. HTTP.SYS then makes a queue for each and every request for each and individual application pool based on the request.
Whenever we create any application pool IIS automatically registers the pool with HTTP.SYS to identify the particular during request processing.

What are the different security settings available in IIS ?

Below are the commonly used IIS Security settings

1 Anonymous
2 Integrated Windows Authentication
3. Basic Authentication
4. Digest Authentication
5. Passport Authentication

For Set security permission you need to go to Virtul Directory > Right Click > Properties > Directory Security
Click on Edit Button .

What is the default authentication settings for IIS ?

Anonymous authentication is the default authentication mode for any site that is hosted on IIS, and it runs under the "IUSR_[ServerName]" account.

What is web garden ?

By default Each Application Pool runs with a Single Worker Process (W3Wp.exe). We can assign multiple Worker Process With a Single Application Pool. An Application Poll with multiple Worker process called Web Gardens. Each Worker Process Should have there own Thread and Own Memory space.

Generally its not recommended to use InProc Session mode while we are using Web Garden.

Where session data stores in case of "In-Proc" Session mode ?

Session data store inside process memory of worker process [ w3wp.exe ] .

How we can create an web garden ?

For creating web graden we need to go to Application Pool, then Right Click on Application Pool > Properties > Goto Performance Tab

In Web Garden Section, increase the number of worker process. By default it is 1.

How we can debug a web application which is hosted on IIS ?

We can easily debug any web application that are hosted on IIS by using Attaching of Worker Process.
From Visual Studio IDE > Tools > Attach To Process
Select the particular Process, then start debugging.

How we can open IIS Configuration manager ?

Just simply Run >inetmgr
Or we can open it from control panel > Administrative tools.

How we can create a Virtual Directory on IIS ?

Open IIS Configuration Manager
First of all Right Click on Default web sites > New > Virtual Directory .
Browse the Physical Path. Set the properites. Click on OK

What are the permission settings are available for Virtual Directory ?

Below are the list of permission that can be set during virtaul directory creation
1. Read
2. Run Scripts
3. Execute:
4. Write:
5. Browse

What is the folder location for Virtual Directory ?

<Drive>:\inetpub\wwwroot

What is the use of Enable Pinging Properties for Application Pool ?

IIS should periodically monitor the health of a worker process [ Idle or not , Time for recycle or not, All Worker process are running properly or not ] .
Pining means, Activation Process monitor Worker process performance, health, idle time etc.
By default it sets to 30s .

Does One Web Application can have multiple Application Pool ?

No. Every Web Application should have one Application Pool. Bydefault it is "DefaultAppPool ".

Which version of IIS is available in Windows Server 2008 ?

IIS 7.0 .

Even Vista Home Premium and Ultimate edition is also having IIS 7.0

How we can save an Application Pool Settings?

Application Pool Settings can be save as "XML" Format.

Right Click on Application Pool > All Task > Save Configuration to a File .

This will save all the settings of Application Pool as an XML file.We can make it password protected also.

Which Tool is used for Remote IIS Debugging ?

Tools is : msvsmon.exe

This is located at : Install path\Microsoft Visual Studio 8\Common7\IDE\Remote Debugger\x86

What are the different authentication mode available for IIS Remote Debugging ?

For IIS Remote Debugging msvsmon supported two authentication mode

1. Windows Authentication
2. No-Authentication

How can we get the list of worker process running in IIS along with the Application pool name ?

By running iisapp.vbs script from command Prompt.

Below are the steps :
1. Start > Run > Cmd
2. Go To Windows > System32 
3. Run cscript iisapp.vbs

If there are multiple worker process running on IIS, then how can you attach a particular worker process for application ?

Well, If there are multiple worker process running in IIS, it means I have to know the name of my application pool. Then I can run cscript iisapi.vbs script to find out the process ID and Application Pool name . Based on the process Id for particular application I have to attache the process from Visual studio IDE.

Why do we need to IIS Remote Debugging ?

There are following reasons where we can use remote debugging
1. Your development server does not have IIS installed.
2. Development server and Build/Released/Hosting Server is different
3. Multiple user want to debug simultaneously.

Does IIS allows multiple user to Remote debug simultaneously ?

Yes. This is one of the great features of msvsmon.exe . Each instance of the remote debugger has a unique server name.we can give an instance of the remote debugger any server name. Now multiple user can able to access the server instance.

What is the use of aspnet_regiis -i command ?

This is used automatically register the .NET Framework with your IIS.

Can we have multiple web sites on IIS ?

Yes. IIS Can have multiple web sites and Each and every web sites can have multiple virtual Directory.

Note : Here web sites means the Root Node.

Where is the default location for IIS Log files ?

Its
C:\WINDOWS\system32\LogFiles\W3SVC1

What is ISAPI Filter ?

This is one of the more important question for experienced guys.

What are the major innovation in IIS 7.0 ?

Below are the Major Innovation in IIS 7.0
Components are designed as module and there are major change in administration settings.
FYI : You can find out many of them, just go thorugh Microsoft IIS web site.

What is the Role of Windows Activation Process in IIS ?

WAP is the Controller of Worker process under a Application Pool. Windows Activation Process which is managed by the worker process by starting, stopping and recycling the application pool. When to start, stop and Recycle should be defined on Application Pool Settings. Activation Process is also responsible for Health Monitor of Application Pool during runtime.

FYI : Health monitoring setting can be easily found in Properties of Application Pool.

What are the different type of application pool available in IIS 7.0 ?

IIS 7.0 having two types of application pool.

1. DefaultAppPool (Integrated)
2. ClassicAppPool

Which is not an Identity of Application Pool ?

NOTE: This is objective type question, Please click question title for correct answer.

Which application pool having maximum privilege on the server ?

NOTE: This is objective type question, Please click question title for correct answer.

What is name of default application pool in IIS ?

NOTE: This is objective type question, Please click question title for correct answer.

What are the worker process for IIS 5.1 and IIS 6.0 ?

For IIS 5.1 > aspnet_wp.exe
For IIS 6.0 > w3wp.exe

Name of the tool which is used for remote debugging of IIS

NOTE: This is objective type question, Please click question title for correct answer.

What is Web Farm ?

This is one of the most question in IIS. And along with that interviewer can as what is the different between Web farm and Web Garden ?

When we hosted our web Application on multiple web server under a load balancer call the Web Farm. This is generally used for heavy load web application where there are many user request at a time. So When Web Application is hosted on Different IIS Server over a load balancer, Load balancer is responsible for distribute the load on different server.

What is the default Identity of an Application Pool ?

NetworkServices

How can we set the default page for any web application ?

We can set the default page for a web site from the Virtual Directory Setting.
How To :
IIS Manager > Virtual Directory > Right Click > Properties > GoTo Document Tab.

How we can set the Idle Time out of an worker process ?

We can set the Idle time out for an worker process from Application Pool Properties.

In Performance Tab of Application pool, we can set the Idle Time out of the worker process. This means worker process will shut down after that given time period if it stay idle. And will again wake up again if a new request comes.

Is there any alternative way to host site on IIS rather than opening IIS Manager ?

Yes, We can directly host any site from the physical location of directory itself.

Right Click on Physical Folder > Properties > Web Sharing

There you need to select > "Share This Folder" Option Button. Then it will ask for alias name and other setting. Then Click on OK.

To Validate : Run > Inetmgr > Check there should an virtual directory with the same "Alias" name that you have given.

If there are already one Virtual directory exist it will showing you the error message while you providing the "Alias" name.

Can we create one Application Pool From Another Application Pool ?

Yes. We can.
While creating Application Application Pool From IIS, there should have two option available first one is for Default Setting and Another is for Existing Setting as template.
We can select the second one and from the drop down listed below we can select any on the Application Pool as Template,.

What are the main components of SVCHost.exe ?

Main components for SVCHost.exe are WWW Publishing Service (W3SVC) and Windows Activation Porcess(WAP) .

W3SVC is the mediator of HTTP.SYS and Windows Activation Process. Windows Activation Process maintain the worker processes.

What are the different way that we can hosted site on IIS ?

We can hosted site on IIS either creating Virtual Directory through IIS manager or Using Folder Web Sharing .
Apart from that Visual studio provide some inbuilt features to host the site on IIS like using Publishing the web site , Using Copy web Tool or Creating Virtual directory during the creating the project by choosing Location as HTTP

How does IIS process an ASP.net request ?

When client request for an aspx pages, request comes to kernel level off IIS means to HTTP.SYS . HTTP.SYSreceives the request and based on the application pool name [ Which is already registred with the HTTP.SYS ] it send the request to worker process. Windows Activation process works as mediator of them. w3wp.exe loads "aspnet_isapi.dll" files to start 

the HTTPRuntime . HTTPRuntime creates HTTPApplication objects and all request are passed through HTTPModule and finally reached to HttpHandler . This is the request pipeline. After end of Request pipeline ASP.NET Page lifecycle starts. 

From where we can set the Session Time Out in IIS ?

We can set the Session time out settings from the Virtual Directory for that site.

Right Click on Virtual Directory > Properties > Click on "Configuration" Button
Goto the "Option" Tab. There in Enable Session State Section you can configure the Session Timeout .

What are the different "Execution Permission" available for IIS for an virtual directory ?

There are three Execution Permission available.
1. None
2. Scripts Only
3. Scripts and Executable

From where you can change the ASP.NET Version in IIS ?

This can be change from Virtual Directory properties. First open Properties of Virtual Directory > GoTo ASP.NET Version Tab.

There we can have change the ASP.NET Version.

What is the latest version of IIS released with Windows 7

IIS 7.5

What is the default user name of an anonymous login in IIS?

In IIS, an anonymous user will be given with a user name of "IUSR_MachineName "

How can we take back-ups in IIS Server?

Step 1 : In the IIS (inetmgr), right click on the "Computer" icon under "Internet Information Services" . Click "All Tasks" and select "Backup/Restore Configuration".

Step 2 : Click on button "Create backup". Give Name for your backup file. If you want encryption enable encryption option and give UserName and Password and then click OK.

What is IIS metabase? And In which format IIS stors configurations?

IIS metabase is a special databse which is used to maintain the settings and configurations data for IIS. In simple term, it is a configuration base for IIS (Metabase.xml).

IIS 5.0 --> Metabse is in Binary.
IIS 6.0 & 7.5 --> Metabase is in XML.

List of Error & Status codes in IIS 6.0?

Status Code Type of Code
100 Series - Informational
200 Series - Success
300 Series - Redirection
400 Series - Client Error
500 Series - Server Error

How to recycle application pool from the command prompt in IIS7?

1. Use appcmd.exe to recycle the application pool from the command prompt.

2. appcmd.exe is the command line tool for IIS7, you will find this tool at following location :

%systemroot%\system32\inetsrv\appcmd

3. To recycle your application pool use the following command:
appcmd recycle apppool /apppool.name:<application pool name>

What are the Different steps to be followed to get SSL(Secure Sockets Layer) for our Web Application ?

. Intially we have to Generate a certificate request from our IIS

. Now we have to request a certificate from the certificate authority(CA)

. This CA is an entity which issues Digital Certificates.

. After receiving the certificate we have to install that particular certificate on our Web Server using IIS

. We have to use Secure Hyper Text Transfer Protocol(HTTPS) when accessing secure pages in our application.

By this way we could make our web page as SSL protected. !!!

Which DLL is used to translate XML to SQL in Internet Information Services (IIS) ?

NOTE: This is objective type question, Please click question title for correct answer.

What is the purpose of IIS application pools?

We use applicaiton pools for isolation purpose. Every application within an application pool used the same worker process. Each worker process operates as a separate instance of the worker process executable, W3wp.exe, the worker process that services one application pool is separated from the worker process that services another.

In simplest words we use applicaiton pools for ISOLATION purpose.

what is Windows Process Activation Service ?

The Windows Process Activation Service (WAS) provides process activation, resource management and health management services for message-activated applications. It manages application pool configuration and the creation and lifetime of worker processes for HTTP and other protocols (net.tcp,net.pipe,net.msmq)

What are the Different Authentication Methods(Using Windows Authentication) which are provided by IIS ?

Generally IIS provides four different kinds of Authentication Methods they are :

Anonymous Method

If we select this authentication, IIS doesn't perform any authentication so that any one can access the application.

Basic Method

If we select this method, the user who access the application should provide windows username and password to access the application. Although this is sent through a network by transmitting direct text so it it very insecure.

Digest Method

This method is almost equal to Basic method but the difference is the password is hashed before it is transmitted through out a network.

Windows Integrated Method

In this the application uses the Kerberos protocol to validate(Authenticate) the user. This uses a Secret key cryptography which provides strign authentication for Client/Server applications.

How can we check whether IIS is being installed in my system or not?

To verify if IIS is installed or not we need to go to ’Add or Remove Programs’ utility in the Control panel and click on the ’Add/Remove Windows Components’ in the side menu.

There we must locate an item called "Internet Information Services (IIS)". If this is checked, IIS should be installed.

So that you can have your IIS installed in your system if it is not installed

How will you call a Website from another computer connected in LAN?

In order to call a website from another computer in LAN.We will have to Host the Website in one Machines in the LAN and provide it a Static Private IP.

Once we are done with, we can treat it as a dummy server.

Once the website is hosted then we can call the website from the Private static IP of the machine in which the web app is hosted.

Eg :- if the web app is named as abc and the private IP is 192.168.1.2

then from another machine we can call the app as

http://192.168.1.2/abc

What is Clustering. Briefly define & explain it ?

Clustering is a technology, which is used to provide High Availability for mission critical applications. We can configure cluster by installing MCS (Microsoft cluster service) component from Add remove programs, which can only available in Enterprise Edition and Data center edition.

Types of Clusters ?
In Windows we can configure two types of clusters

1. NLB (network load balancing) cluster for balancing load between servers. This cluster will not provide any high availability. Usually preferable at edge servers like web or proxy.

2. Server Cluster: This provides High availability by configuring active-active or active-passive cluster. In 2 node active-passive cluster one node will be active and one node will be stand by. When active server fails the application will FAILOVER to stand by server automatically. When the original server backs we need to FAILBACK the application

What is Quorum ? A shared storage need to provide for all servers which keeps information about clustered application and session state and is useful in FAILOVER situation. This is very important if Quorum disk fails entire cluster will fails.

Why Quorum is necessary ?

When network problems occur, they can interfere with communication between cluster nodes. A small set of nodes might be able to communicate together across a functioning part of a network, but might not be able to communicate with a different set of nodes in another part of the network. This can cause serious issues. In this “split” situation, at least one of the sets of nodes must stop running as a cluster.

To prevent the issues that are caused by a split in the cluster, the cluster software requires that any set of nodes running as a cluster must use a voting algorithm to determine whether, at a given time, that set has quorum. Because a given cluster has a specific set of nodes and a specific quorum configuration, the cluster will know how many “votes” constitutes a majority (that is, a quorum). If the number drops below the majority, the cluster stops running. Nodes will still listen for the presence of other nodes, in case another node appears again on the network, but the nodes will not begin to function as a cluster until the quorum exists again.

For example, in a five node cluster that is using a node majority, consider what happens if nodes 1, 2, and 3 can communicate with each other but not with nodes 4 and 5. Nodes 1, 2, and 3 constitute a majority, and they continue running as a cluster. Nodes 4 and 5 are a minority and stop running as a cluster, which prevents the problems of a “split” situation. If node 3 loses communication with other nodes, all nodes stop running as a cluster. However, all functioning nodes will continue to listen for communication, so that when the network begins working again, the cluster can form and begin to run.

Different types of Quorum in Windows server 2008 ?

1.Node Majority – Used when Odd number of nodes are in cluster.
2.Node and Disk Majority – Even number of nodes(but not a multi-site cluster)
3.Node and File Share Majority – Even number of nodes, multi-site cluster
4.Node and File Share Majority – Even number of nodes, no shared storage

Different types of Quorum in Windows server 2003 ?

Standard Quorum : As mentioned above, a quorum is simply a configuration database for MSCS, and is stored in the quorum log file. A standard quorum uses a quorum log file that is located on a disk hosted on a shared storage interconnect that is accessible by all members of the cluster.
Standard quorums are available in Windows NT 4.0 Enterprise Edition, Windows 2000 Advanced Server, Windows 2000 Datacenter Server, Windows Server 2003 Enterprise Edition and Windows Server 2003 Datacenter Edition.

Majority Node Set Quorums : A majority node set (MNS) quorum is a single quorum resource from a server cluster perspective. However, the data is actually stored by default on the system disk of each member of the cluster. The MNS resource takes care to ensure that the cluster configuration data stored on the MNS is kept consistent across the different disks.

Majority node set quorums are available in Windows Server 2003 Enterprise Edition, and Windows Server 2003 Datacenter Edition.

Explain about each Quorum type ?

Node Majority: Each node that is available and in communication can vote. The cluster functions only with a majority of the votes, that is, more than half.

Node and Disk Majority: Each node plus a designated disk in the cluster storage (the “disk witness”) can vote, whenever they are available and in communication. The cluster functions only with a majority of the votes, that is, more than half.

Node and File Share Majority: Each node plus a designated file share created by the administrator (the “file share witness”) can vote, whenever they are available and in communication. The cluster functions only with a majority of the votes, that is, more than half.

No Majority: Disk Only: The cluster has quorum if one node is available and in communication with a specific disk in the cluster storage.

How is the quorum information located on the system disk of each node kept in synch?

The server cluster infrastructure ensures that all changes are replicated and updated on all members in a cluster.

Can this method be used to replicate application data as well?

No, that is not possible in this version of clustering. Only Quorum information is replicated and maintained in a synchronized state by the clustering infrastructure.

Can I convert a standard cluster to an MNS cluster?

Yes. You can use Cluster Administrator to create a new Majority Node Set resource and then, on the cluster properties sheet Quorum tab, change the quorum to that Majority Node Set resource.

What is the difference between a geographically dispersed cluster and an MNS cluster?

A geographic cluster refers to a cluster that has nodes in multiple locations, while an MNS-based cluster refers to the type of quorum resources in use. A geographic cluster can use either a shared disk or MNS quorum resource, while an MNS-based cluster can be located in a single site, or span multiple sites.

What is the maximum number of nodes in an MNS cluster?

Windows Server 2003 supports 8-node clusters for both Enterprise Edition and Datacenter Edition.

Do I need special hardware to use an MNS cluster?

There is nothing inherent in the MNS architecture that requires any special hardware, other than what is required for a standard cluster (for example, there must be on the Microsoft Cluster HCL). However, some situations that use an MNS cluster may have unique requirements (such as geographic clusters), where data must be replicated in real time between sites.

Does a cluster aware application need to be rewritten to support MNS?

No, using an MNS quorum requires no change to the application. However, some cluster aware applications expect a shared disk (for example SQL Server 2000), so while you do not need shared disks for the quorum, you do need shared disks for the application.

Does MNS get rid of the need for shared disks?

It depends on the application. For example, clustered SQL Server 2000 requires shared disk for data. Remember, MNS only removes the need for a shared disk quorum.

What does a failover cluster do in Windows Server 2008 ?
A failover cluster is a group of independent computers that work together to increase the availability of applications and services. The clustered servers (called nodes) are connected by physical cables and by software. If one of the cluster nodes fails, another node begins to provide service (a process known as failover). Users experience a minimum of disruptions in service.

What new functionality does failover clustering provide in Windows Server 2008 ?
New validation feature. With this feature, you can check that your system, storage, and network configuration is suitable for a cluster.

Support for GUID partition table (GPT) disks in cluster storage. GPT disks can have partitions larger than two terabytes and have built-in redundancy in the way partition information is stored, unlike master boot record (MBR) disks.

What happens to a running Cluster if the quorum disk fails in Windows Server 2003 Cluster ?
In Windows Server 2003, the Quorum disk resource is required for the Cluster
to function. In your example, if the Quorum disk suddenly became unavailable
to the cluster then both nodes would immediately fail and not be able to
restart the clussvc.

In that light, the Quorum disk was a single point of failure in a Microsoft
Cluster implementation. However, it was usually a fairly quick workaround to
get the cluster back up and operational. There are generally two solutions
to that type of problem.

1. Detemrine why the Quorum disk failed and repair.
2. Reprovision a new LUN, present it to the cluster, assign it a drive
letter and format. Then start one node with the /FQ switch and through
cluadmin designate the new disk resource as the Quorum. Then stop and
restart the clussvc normally and then bring online the second node.

What happens to a running Cluster if the quorum disk fails in Windows Server 2008 Cluster ?

Cluster continue to work but failover will not happen in case of any other failure in the active node.

What must be done to an AD forest before Exchange can be deployed?

What must be done to an AD forest before Exchange can be deployed?

Setup /forestprep 

What is Active Directory?

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.

Active Directory Partitions?

What are the Active Directory Partitions?

The AD database is divided up into partitions for replication and administration. This video looks at the different partition types and how the partition type effects replication. 

Partitions
Each Domain Controller has a copy of the Active Directory database store in a file called NTDS.DIT. The data in this file is divided into partitions. The partition type determines how it will be replicated throughout the forest. For example, the domain partition is only replicated to Domain Controllers in that domain, while the Global Catalog partition is replicated to all Domain Controllers in the forest.

Domain Partition
This partition is replicated only to Domain Controllers in that domain. Active Directory Users and Computers obtains it data from this partition. All Domain Controllers in that domain replicate changes to each other regardless of whether the Domain Controller is a global catalog server.

Global Catalog Partition
This partition is also referred to as Partial Attribute Set (PAS) in some documents. The partition contains a partial replica of all objects in the domain. It is replicated to all Global Catalog Servers in the forest.

The Global Catalog Partition is created automatically by software on the Domain Controller. This software copies some of the attributes for each object in the Global Catalog Partition. This information is replicated to other Domain Controllers inside and outside the domain. This is how, given enough time, all Global Catalog servers will have a partial replicate of all objects in the domain.

Schema Partition
The schema partitions define what can be stored in the Active Directory database. It essentially defines the layout of the database.  The schema partition is replicated to all Domain Controllers in the forest and defines the Active Directory database for all Domain Controllers in the domain.

Configuration Partition
This partition contains configuration information for the whole forest. For example, it contains information about sites in the forest and partition defined in the Active Directory database. This partition is replicated to all Domain Controllers in the forest.

Application Partition
The application partition is created by Applications to store their data. It is different from any other partition in that the application can choose which Domain Controller or Controllers to store the data on. The advantage for the application storing the data this way is that the application has access to the same replicate and fault tolerance used by the Domain Controllers. An example of an Application is DNS Integrated Active Directory Zones. When this zone type is used, the data is stored in an application partition.

Demonstration
ADSI Edit is a low level tool that can be used to modify data in the Active Directory database. It is recommended that you use the built in tools like Active Directory Users and Computers to modify data in the Active Directory database. These tools should only be used in rare troubleshooting scenarios in which the regular tools are not working as expected.

Windows Server Admin Interview Questions and Answers

Windows Server Admin Interview Questions and Answers