Archive for the ‘Group Policy’ Category.

Time Synchronization for Virtualized DCs

As usual a good conversation spurred on ActiveDir on a much discussed scenario of virtualizing your DCs while be varied of the known pitfalls. While virtualized DCs are fully supported on either competing virtualization solution by Microsoft, one known subject I would like to highlight here is the proper time synchronization. You must make sure that your PDCe gets its time from an external time source and other DCs follow the PDCe. All DCs (including PDCe) must not sync their time with the virtualization host, whether its VMware ESX or that of Hyper-V. It was discussed how by default the VMware’s VM settting does not have the time synchronization enabled by default, and my brief look at the Hyper-V’s VM suggested that it is. In any case, you must make sure that setting is disabled, thus VM does sync its time with its host.

VMware time setting from the VMware tools within the VM:

VMwareTS

Or under the VM settings from VIC :

VMwareTS2

Hyper-V setting from the VM settings :

HyperV-TS

A great resource to refer to, to learn how to configure an authoritative time source for your DCs – see this KB http://support.microsoft.com/kb/816042

Is there an Active Directory Visual Illustration/Diagram ?

A question was raised on ActiveDir, and I learned about an old TechNet Jigsaw on AD’s interworking.

ADjigsaw

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Along with that, there was a new Windows Server 2008 AD Feature Components which I received at Tech-Ed 2007 and it illustrates the new and improved AD pieces introduced with Windows Server 2008. This poster covers ADLDS, ADFS, ADRMS, and RODCs.

 

AD08features

And an additional poster on general new Windows Server 2008 Feature Components that covers TS, NAP, IIS 7.0, Virtualization, Server Core and BitLocker.

08features

Both of the above illustrations and very good quality large size posters (30x20in) and are good to hang in your office/cube. Printing them on regular printer may distort the quality, so you may try the plotter :) . All three can be downloaded from the following links :

TechNet Magazine Active Directory Component Jigsaw Poster

Windows Server 2008 Component Posters (both)

P.S This is my first test post using WLW.

Exchange 2010 goes Release Candidate today !

You can get an evaluation copy here.

exum131

 

 

 

Scott Schnoll had a great post on how to install the beta, with all the gotchas and a long list of pre-reqs.

http://blogs.technet.com/scottschnoll/archive/2009/04/15/how-to-install-exchange-server-2010.aspx

As Exchange 2010 will only run on Windows Server 2008 (64bit only), there were some known issues with the beta version with the Windows Server 2008 R2 (mainly newer builds than 7000), due to PowerShell and WinRM stacks being incompatible. That issues is well discussed here and hopefully those issues are now resolved with the RC.

http://social.technet.microsoft.com/Forums/en-US/exchange2010/thread/e73ec63f-d5f6-4c2d-8d96-51537493a0ff

And here is the system requirements list.

http://technet.microsoft.com/en-us//library/aa996719(EXCHG.140).aspx

Find out where and why an Account Lockout happened

Where Account Lockouts save us from brute force password attacks and help us standardize our environment for password policies, sometimes it can be painful to troubleshoot and find out why and where it happened. Microsoft does provide us with the ‘Account Lockout Management Tools’ suite which can be very handy to diagnose the root cause of an account lockout.

· AcctInfo.dll. Helps isolate and troubleshoot account lockouts and to change a user’s password on a domain controller in that user’s site. It works by adding new property pages to user objects in the Active Directory Users and Computers Microsoft Management Console (MMC).

· ALockout.dll. On the client computer, helps determine a process or application that is sending wrong credentials.

· ALoInfo.exe. Displays all user account names and the age of their passwords.

· EnableKerbLog.vbs. Used as a startup script, allows Kerberos to log on to all your clients that run Windows 2000 and later.

· EventCombMT.exe. Gathers specific events from event logs of several different machines to one central location.

· LockoutStatus.exe. Determines all the domain controllers that are involved in a lockout of a user in order to assist in gathering the logs. LockoutStatus.exe uses the NLParse.exe tool to parse Netlogon logs for specific Netlogon return status codes. It directs the output to a comma-separated value (.csv) file that you can sort further, if needed. The latest version available is 1.0.0.60.

· NLParse.exe. Used to extract and display desired entries from the Netlogon log files.

Unfortunately, I didn’t find good documentation of how to quickly make good use of these tools when my domain admin account started getting mysteriously locked out after I had changed my password due to the policy in place. From my experience I found Lockout Status and EventComb MT to be most useful from the suite.

I knew the common causes why my account would get locked out due to one of the reasons listed here : See this but I needed to figure out what is the offending machine or service thats providing my old credentials to a DC thats causing the account to be locked out.

I started out launching Lockout Status tool and selected my domain admin account as ‘target’ from the file menu and running it. It gave me list of all the DCs with the status of my account and more importantly the DC the lockout happened on in the ‘Orig Lock’ tab towards the right of the program screen. I then launched the Event CombMT piece and right clicked in the white space in the search area and added the DC the lockout originated at. I choose from ‘Option’ menu where I wanted to output the file as txt or CSV. I chose ‘Security’ as log files search option for all event types and then putting ’644′ as the event id and clicked on search.

It outputted the CSV file in the area I had specified and I was able to see that it found the event 644 for my ID on 6 different machines across the domain, it was listed under ‘Caller Machines Name’ column, (I know its bad administration on my part to sometimes disconnect my terminal sessions instead of logging off). Sure enough when I logged on to those machines I immediately saw the following notifications.

alock.JPG

alock2.JPG

I had to log off and log back in to clear out the error. After that, I ran the Lockout Status tool again and noticed the lock status for my domain admin account had been cleared out.

Conclusion: Never leave your account logged on somewhere (or have a service run under your user context) and lock the machines or disconnect the remote session without logging off, and when using tools like Remote Desktops (which can be useful and allow you to have a list of machines you remote in frequently during the day), make sure you don’t save your passwords in the session configurations.

More Resources:

Download the Microsoft Account Management Tools

Technet Resource on how to maintain and manage the account lockout

WindowsSecuirty.com-Implementing and Troubleshooting Account lockout

Group Policy Basics

Group Policy has been an extremly handy tool for last few years for System Admins, yet an equally complex topic to digest and you need to know it inside-out in order to effectively troubleshoot the problems that occur from time to time in your environment. Lets start with the basics of Group Policy Mechanism.

A GPO is a virtual object. The policy setting information of a GPO is actually stored in two locations: the Group Policy container (GPC) and the Group Policy template (GPT). The Group Policy container is an Active Directory container that stores GPO properties, including information about version, GPO status, and a list of components that have settings in the GPO. The Group Policy template is a directory structure within the file system that stores Administrative Template-based policy settings, security settings, script files, and information regarding applications that are available for Software Installation. The Group Policy template is located in Sysvol in the \Policies sub-directory for its domain. GPOs are identified by their globally unique identifiers (GUIDs) and stored at the domain level. Replication of a GPO to other domain controllers happens through two different mechanisms. The Group Policy container is replicated by using Active Directory replication (RPC), whereas the Group Policy template is replicated using File Replication service (FRS) in Windows Server 2003 and for Windows Server 2008 (native domain) DFSR. The settings from a GPO are only applied when the Group Policy container and Group Policy template are synchronized.

 More on Group Policy later.

WSUS 3.0 SP1 gets released

WSUS 3.0 SP1 was released yesterday, following are the improvements that have been made from Version 3.0.6

The improvements that SP1 offers include:

• Support for Windows Server 2008.
• New Client Servicing API.
• Support client registration.
• Filter of updates by category and classification.
• Provide applicability rule extension mechanism.
• Obtain package metadata and report update status for each client.

• Improvements for local publishing: supports publishing of drivers within the enterprise by using vendor provided catalogs. API include support for bundles and prerequisites.
• All hotfixes: WSUS 3.0 SP1 includes all the changes and hotfixes that have been issued since the release of WSUS 3.0.
• Support for Microsoft SQL Server 2005: WSUS 3.0 SP1 lets you use SQL Server 2005.

You can get it here..