Re: Problems with second DC (failover) when primary DC is offline.



"Joe M" <JoeM@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:606437D0-F739-4A5A-844B-C35DF8FDC727@xxxxxxxxxxxxxxxx
> We have a Windows 2003 server as our DC. we have decided to add a second
> windows 2003 server as a second Dc, incase of any problems with the
> primary
> DC. They are both set up with DHCP, DNS, WINS, they are both GC. Both
> IPs
> are being distributed by DHCP as DNS and WINS servers.

Are WINS and DNS servers (set to) replicating properly?

Run DCDiag on each DC and (otherwise) check the WINS server replication.

> Both reference each other's IPs as DNS and WINS servers.

Does each ALSO reference itself or JUST the other server.

Generally case is each DC/DNS should use ITSELF first and
it's "partner" second (as alternate) for DNS (and WINS) server.


> However, when the main DC is offline,
> no one can log onto any pc, including the secondary DC itself.

Check the replication of DNS -- your problems are usually
symptoms of failure to replicate DNS.

DCDiag is your friend.

Make sure all clients are using STRICTLY and BOTH of these
servers for DNS (IPconfig /all ) -- when one is down, a frequent
problem is that the clients are only set to use the missing DNS
and so cannot find the "other DC.".

> It says that the domain cannot be located. Anyone have ideas or
> suggestions
> as to what I might be overlooking? I realize I haven't included all
> details
> here, but I didn't want the post to become too long....
> thanks


Fixing DNS is almost always the answers. (Check time [ within
5 minutes on all machines] and for firewall/routing problems but
it is usually a DNS issue.

Either the DCs are not properly registered; the DNS is not replicated;
or the DNS clients are not using STRICTLY (and both) of the internal
DNS servers.

--
Herb Martin, MCSE, MVP
Accelerated MCSE
http://www.LearnQuick.Com
[phone number on web site]

>


.



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