Showing posts with the label Windows Server 2008

DCLocator | Acitve Directory Client logon

                                 The netlogon service in DC is responsible for registering SRV records in the DNS server under It then registers the SRV records of Domain Controller under based on their site location.

Automatic Site Coverage | Active Directory

                          In an Active Directory environment where you have at least a single Domain Controller, the clients in that site will contact this Domain Controller for handling service requests. But suppose, you have a site without a Domain Controller (yes, it is possible). In that scenario, which Domain Controller does the client contact for handling its service requests. This is where the Automatic Site Coverage comes into play!!!

Using Automatic Site Coverage, each Domain Controller checks all sites in the domain and calculate replication cost matrix. Thus the Domain Controller from a site which appears as the closest one (using site link cost calculation) to the site without Domain Controller will advertise itself as the authoritative one. If there are multiple sites with the same cost link to the site without Domain Controller, then the site with the most number of Domain Controllers will be chosen. If the tie appears here as well, the site which comes in first alphabet…

Redirect HTTP to HTTPS in IIS 7

It is quite often that we host websites initially as HTTP sites in IIS and suddenly one day, the IT security geek comes and say that the website needs to be run in HTTPS.

There are a few methods by which this could be achieved.

The one method I'm gonna share with you in this blog is the redirection using URL Rewrite Module. This is an IIS module which will be available for download from this Microsoft site.

Once installed, the plugin will be available under the options of a website.

PsExec tool

This is a simple but elegant tool. A tool which is known to all system adminstrators, but still not used as often as it should be. PsExec is a tool which comes as part of PsTools suite from Microsoft which is used to execute programs in machines remotely. 

PsExec lets you execute processes on remote systems and redirects the output to the local system without having to manually install client software. 

Are you wondering why it is different from Microsoft Telnet ? Of course, no client required on the remote machine as in case of Telnet.

Does my SQL server require memory upgrade ?

               The memory usage of SQL servers is always a hot topic among the system administrators. Any system administrator who handles a SQL server in their environment would have definitely faced this issue.

Before going on to the memory monitoring of SQL, we should have answers to the below questions :
What does SQL do with the memory ?Does it handle memory in the same way as other applications do ?SQL server uses memory for :

Empty Recycle Bin for all user profiles

As a system administrator it is quite often that you would experience disk space issues in OS. Most often, the culprit would be Recycle Bin space.

When a user deletes a file, it is moved to Recycle Bin (Unless this is done with Shift key pressed). Recycle Bin is specific to user profiles and therefore when we empty recycle bin, all the contents of the particular user's recycle bin gets emptied.

How can we empty recycle bin of all users ?

Active Directory Recycle Bin

Focus: Active Directory Recycle Bin

Active Directory Recycle Bin

This is a new feature of Windows 2008 R2 which is disabled by default. This feature will be available only if your forest functional level is Windows 2008 R2 and above. Once you enable this feature, it cannot be disabled.

How to enable?

There is no GUI to enable AD recycle binOpen powershell execute the below:Import-Module ActiveDirectoryEnable-ADOptionalFeature -Identity "Recycle Bin Feature" -Scope ForestOrConfigurationSet -Target "globomantics.local" -whatif

Active Directory Tombstone

Focus: Active Directory Tombstone, TSL, Tombstone reanimation

Active Directory Tombstone

When an object is removed from Active Directory, it is said to be tombstoned. Tombstone is something which a Domain Controller uses to notify other Domain Controllers about an object deletion.

Active Directory Authoritative and Non Authoritative restore

Focus: Authoritative and Non Authoritative restoration

Non Authoritative Restore
Non-Authoritative restore brings back the DC to its state at the time of backup.After the restoration, other DCs will replicate with the newly restored DC with the changes occurred after the backup.This method is mainly used when a DC fails due to hardware/software issue.Non-Authoritative restore is performed in Directory Service Restore Mode (DSRM).

Active Directory USN Rollback

Focus: USN, USN Rollback, DSA GUID and Invocation GUID

Unique Sequence Number (USN)

USN is an AD database change tracking number. Any change or transaction made in a DC is represented by a USN increment. The USN of DCs in the same domain need not be same.

Active Directory Replication Explained

Focus: Active Directory Replication, USN, HWMV and UTDV

                                   Intrasite replication replicates changes made in one DC to all other DCs in the same site. AD replications are generally pull operations. For example (A site with two DCs : DC1 & DC2) , If a change is made on DC1 then DC1 will inform DC2 about the change.

Software installation using group policy

This can be done in 2 methods

Contents of System State Backup

The content of the system state backup includes:

RegistryCOM+ Class Registration databaseBoot files, including the system files

Group Policy in a nutshell


GPO - Group Policy Object : Refers to the policy that is configured at the Active Directory level and is inherited by the domain member computers. You can configure a GPO at the site level, domain level or OU level. GPO stores policy settings in two locations GPC and GPT


When you boot your Windows 2008 R2 OS, the machine gets halted with a blue screen error. The error will have the below information:
Technical Information:
*** STOP: 0x000000D1 (Some address values) *** tcpip.sys – Address information

Extend Windows Server 2008 evaluation period

By default Windows Server 2008 runs 60 days without being activated. But after this period, the server will prompt the annoying message during login "Evaluation period expired". Microsoft itself provides a tweak for this by extending the evalutaion period. The evaluation period can be extended for another 60 days upto three times. So in effect we can run the server for 180 + 60 days.

This could be done by executing the below commands:

To view the license status

slmgr.vbs -dli 

To extend for 60 days

slmgr.vbs -rearm