BDC online but clients dont use it.

[jmair]

I finally added a Backup Domain Controller yesterday. I've got to be missing a step though. When I take down my primary Domain Controller (restart or just unplug the cat5) users can't log onto the domain.

Other than adding the secondary domain controller to the network, is the something I need to do afterwords in order for it to be recognized by on the domain so clients can log in?
(I've checked the both DCs and have seen that the records swap and that both servers are domain controllers.. or it appears to be that way anyhow.)

I'll be happy to provide any info to help solve this little problem.. Thanks!

[ezzauk]

Have you made the BDC a Global Catalog?

[jmair]

NOPE! I'll look that up now.. and thank yuo for the quick reply!

[TheLibrarian]

Ensure that it is listed as a DNS server in the DHCP options.

If you only have the primary server as a DNS server and it goes missing...

[jmair]

Global catalogue -CHECK
DHCP and DNS Installed - CHECK
DNS Replication - CHECK
Able to see both servers from both servers in AD Sites/Services and DHCP (scope identical to primary dns)

Still when I unplug the Primary DNS, clients cannot log into the domain. Shouldn't the BDC just take over transparently? I know I'm missing something, any ideas other ideas?

[ZeroHour]

One thing to consider is that you can only run one instance of DHCP generally so you never really have a fail over option. If thats on your PDC and you reboot a PC it wont get dns ip's or anything really which would break it. To get around this at our end our DHCP is a clustered service in windows 2008 r2.

[jmair]

I have to take the PCD down to make some serious changes, and to clean the dusty beast. What would you suggest to have the network functional while the PDC is offline?

[ZeroHour]

I would probably move DHCP for now as per: How to move a DHCP database from a computer that is running Windows NT Server 4.0, Windows 2000, or Windows Server 2003 to a computer that is running Windows Server 2003 and then test the network then and if it all works continue with your maintenance. As for dead PDC situations you will have more pain then which is why we clustered the service.

[glennda]

One thing to consider is that you can only run one instance of DHCP generally so you never really have a fail over option. If thats on your PDC and you reboot a PC it wont get dns ip's or anything really which would break it. To get around this at our end our DHCP is a clustered service in windows 2008 r2.

not sure if its the same with 2008 but we have two seperate DHCP servers and have no problems, aslong as you don't have the two servers giving out the same addresses for example my range is as follows 192.168.114.1 - 192.168.124.254. server one leases 114.1 to 119.255 and server 2 leases 120.1 to 124.254.

in your dns ensure there is a record that says something "same as parent folder" with the address of the domain controller and the same for the secondary dc.

aslong as the clients have the dns settings of the bdc you should be able to ping domainname.local which should resolve to either of your domain controllers