Redundancy for the Windows SBS DC Role

Posted on 2011-10-15
Last Modified: 2012-05-12
If an SBS box (hence the PDC for the network) goes down, and it's the only server on the network, how can/do users continue to authenticate?

Background: A client's network has a single server that runs Windows SBS 2003 . The SBS is used only as a domain controller and for file sharing -- no other SBS features are used. There is also NAS .

I am not worried about file system redundancy, as the SBS file system data is replicated on the NAS several times a day. If the server were to go down and stay that way, the (few) users on the network would remap their network drives from the SBS box to the NAS and have access to a very recent version of their files. For this customer, this is adequate, as they are extremely cost-sensitive.

So, what do I need to do to back up the SBS DC functions, if anything? Can users run off cached credentials for the couple of days it might take to bring a seriously ill server back online? A second server running Server Standard Edition and acting as BDC seems like overkill.

Thanks very much.
Question by:rmccraw
    LVL 38

    Accepted Solution

    The only way to have a backup for the DC functions is to have another DC.  Yes, clients can log on to workstations with cached credentials.  Do they need to authenticate to access the NAS?  If the authentication to the NAS is via Active Directory, then when the SBS is down they wouldn't be able to access the NAS.  How about printer sharing?  In effect, workstation logons will be fine, anything else requiring authentication to AD will not work.

    Also, is all internet traffic routed through the SBS (usually only done with SBS Premium)?  In that case internet traffic would be affected.

    Also don't forget about DNS.  All your clients should be pointing to the SBS for DNS.  If it's down, internet browsing would be hampered until you reconfigured the clients to point to a new DNS server.

    Honestly, a small office can function just fine with a single SBS.  But is sometimes a pain to do maintenance, since any restarts of the server can disrupt communication, even if only for a few minutes.

    Author Comment

    Happily, there is no printer sharing, and no authentication is required to hit the NAS. (I was never able to get AD support running in the NAS, and maybe that's a good thing.)

    Thanks for reminding me about DNS. Yes, the SBS box supplies DNS for the clients, but it's nothing fancy. They can work around that problem without much trouble.

    Sounds like they're good to go. Thank you for the quick response.

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