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I have a Windows Server 2003 SP2 server which is running as Active directory for my forrest.

I observed that "netlogon" service is frequently stopping automatically as it results unable to use the nwtwork resources.

For this I want to use a Failover server for AD, means I will create another server as ADC and then i will configur it into cluster so when the ADserver fails the ADC01 will come online automatically.

Is it possible? Can any one help to achieve this?


I have configired sites in my AD with 2 cases

Case 1: let say One Site is not not replicating properly,then how the domain users will authenticate? Also how could I know to which site the users are getting authenticated

Case 2: If my AD servers which holds all the FSMO roles is down with some reason,At this stage how could I get failover i.e how to automatically enable another server to hold the all FSMO roles and users authentication.

Please note The AD and all servers are running on Windows 2003 SP2 Enterprises as OS.

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I really think you might want to search your logs to find out why netlogon is dying first...adding more machines won't be a big help until you know why your primary system here is dying! – Bart Silverstrim Dec 4 '09 at 13:23

The other answers cover the fact that you can just add more DCs to add redundancy. One other thing that is relevant here is netlogon should not be stopping in a healthy environment. It would be a good idea to dig through the event logs and find out what is causing this to happen. I know of one known issue where netlogon will pause when disk space is low (less than 512MB seems to come to mind).

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I think you're missing part of the point of active directory. If you're set up to create another server you don't want to have only one running, you have both of them running all of the time, both configured as Domain Controllers. The way to do this is to install the second server, then DCPromo it to become a domain controller. Active Directory will pretty much handle the automatic synchronization between the servers.

For more redundancy in some areas you can use DFS rather than going directly to shares on the individual servers - that way if the files are on both servers you don't lose access if one server is down.

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Active Directory doesn't use failover clustering; when you have multiple DCs in one domain, they are automatically kept in sync and all of them service client requests. You only need to add as many DCs as you need to the domain, and AD will do the rest.

This can get a bit more complex if you have multiple domains and/or mutiple sites, but for a single site/single domain deployment like yours, that's pretty much all you need.

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Hai ..

I think this guid will help you..

Best wishes

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