Added a new DC to the network, what to do with DHCP/DNS?

[Jamie_Evans]

Hi edugeeks!

 

I've just recently added a new Domain Controller to my network (2012 R2) and have already promoted it to the Primary Domain Controller (Transferred FSMO roles & changed IP to the old DC's address etc).

 

Question now is do I transfer the DNS/DHCP server from the (what I now call) backup Domain Controller (2008 R2) or do I create new DNS/DHCP servers on the new DC and have the old ones act as another backup?

 

First time doing this in my 4 years in IT and I'm wondering what's considered best practice for such a situation.

 

Thanks in advance.

[ricki]

Are you getting rib of the old domain controller and why have you changed to the ip address from the old server. Get the dns to replicate to all domain controllers and then add second dns server to dhcp

[Jamie_Evans]

Are you getting rib of the old domain controller and why have you changed to the ip address from the old server. Get the dns to replicate to all domain controllers and then add second dns server to dhcp

Thanks for your reply Ricki.

 

I plan to keep the old DC up as a backup controller, I changed the IP because I've heard client computers are very likely to lose their connections to the domain if the original servers connecting address has changed. Is that incorrect?

 

So connect to the old DCs DNS and use the same one across 2 different DCs? will they replicate off each other on both DCs? what would be the down side of just creating a new one on the new server and having the old one stay as a backup?

 

Should I also do this with DHCP? if so do I create a new one as well and split the scope or just connect to the old one and have them both replicate to each other?

[ADMaster]

Your dns should be an active directory integrated zone which means it will replicate to all the DC’s

Traditional DHCP doesn’t replicate, I’m not sure about the new IP planning tools in 2012 though.

You do not want to allow both servers to be an active DHCP server, serving the same address range, you will cause conflicts. It is possible to have each server serve a different segment of the network if you really want to.

It is best practice to have at least two DC’s, do you plan to retire the other one, or just wanted to have the redundancy.

If you plan to retire it I would migrate the DHCP to the new server, if it will continue to be an active second DC it’s up to you really.

 

Cheers

[edutech4schools]

r do I create new DNS/DHCP servers on the new DC

 

If you have already run dcpromo you should already have DNS on the new server and it should already be populated.

[3s-gtech]

DHCP can be configured to replicate if you have two 2012 / R2 DCs, but if you're keeping the 2008 R2 server I would transfer the role.

[MordyT]

Of course there is a 2 line powershell you can run that will export dhcp with everything (scope, leases, etc) from the old server and another 2 line to import into the new server. Then you just have to stop the service on the old server.

[themightymrp]

I've used the command line option before to export the current dhcp config and import it to a different server. Was quick and easy from what I remember, and it keeps all of your scopes/reservations etc

[bicky]

Backup DHCP by following steps:

From command prompt on old DHCP server navigate to a command prompt

C:\>netsh DHCP server export c:\bkpDHCPdb all

 

then copy the above file to the new Server 2012 DHCP server and use following command:

C:\>netsh DHCP server import c:\bkpDHCPdb

now restart the DHCP service

 

Make sure to stop the DHCP service from the old server.