Domain Controllers Advice

[Gibbo]

I've just turned off the "main" domain controller after some Windows updates and general Summer housekeeping only to find that the other domain controller isn't taking over and handling logons - I'm just getting "Domain is not available" on the client machines.

 

Is there any kind of checklist I can refer to so I can find out why the other controller isn't kicking in?

 

Is it something simple like a group policy entry or is there more to it?

 

Thanks

[Heebeejeebee]

Is the second domain controller configured as a Global Catalogue?

 

HBJB

[Gibbo]

Not sure. DCs aren't my thing.

[cookie_monster]

Was that DC the DNS server as well? If it is then this is why your clients can't find the other DC.

[Gibbo]

Yes it was. I thought the other domain controller had DNS running but it doesn't. Should it?

 

Should there be anything in group policy? I've checked one policy (for pupil accounts) and that has just the one DNS server IP address in. Yet the staff policy doesn't

Edited August 4, 2008 by Gibbo

[strawberry]

you need dns to hold the record that shows the computers where the dc is. you'll need to set up dns on the second server and set it up in the dhcp options so each comptuer has 2 dns records, one for each dc.

[cookie_monster]

Yes exactly if you want to take down your DC with DNS on for any length of time the second DC will need DNS installed and your clients will need it set as their secondary DNS server.

[localzuk]

Is DHCP also running on the DC that was taken down? If so, you'll hit problems with that too.

[Gibbo]

Yes, it was also running DHCP.

 

I'm just trying to build a bit of redundancy into this really bad network just in case the server fails. I've got no funding and no support so I have to make do with what I can scrounge.

[strawberry]

dhcp is fairly easy to build redundancy into

 

DHCP Scope split & Reservation : Network Infrastructure Servers : Windows Server : Microsoft TechNet Forums

 

for your dc's your best setting them both as dns servers, then add the dns servers into the scope so each machine has both servers set for dns.

[kooperthedog]

Hi Gibbo,

 

We run DHCP failover at each of our secondary schools. We have three servers per school undertaking various tasks, and two of these are configured as DHCP servers.

 

We allocated each school twice as many IP addresses as they required, and then split the scope evenly between the two DHCP servers. The main DHCP server scope at each school hosts the first two ranges (XXX.XXX.4.1 thru XXX.XXX.5.254) and the secondary DHCP server the "spare" ranges (XXX.XXX.6.1 thru XXX.XXX.7.254).

 

This effectively means we could lose one of the DHCP servers as the other has enough IP addresses in it's scope to cover the whole school if required.

 

It might not fit into your environment, but it's a handy approach if you have enough IP ranges available.

 

Cheers,

 

K.

[Gibbo]

Thanks for the replies so far. I've printed off loads of info for some reading tonight.

 

It would be great if there was anyone local to drop by and look over the system and get some advice on best practices. The DCHP scope also needs looking at. Its a 255.255.255.0 network with just x.x.x.25 to x.x.x.254 available.