Windows Server 2008 R2 - DHCP Failover

Question

We currently have 2 domain controllers for failover running Windows Server 2008 R2.

Is it possible to mirror DHCP scopes on both DC's?

Also how do I go about finding what settings were originally entered in order to mirror this on the second DC ?

Solution 1

As TomTom says, the solution is to SPLIT the scope not MIRROR it. Please note that this is a very important distinction because for high availibity, you need enough IP addresses in each half of the scope to support all connecting clients.

Server 2008 R2 makes this extra easy for you:

• Open DHCP Management
• Expand everything so you can see each individual scope
• Right click on the scope, goto advanced and select "Split-Scope"

You can then use this wizard to automatically split your scope into two and create it on the other DHCP server.

Solution 2

You can use a Failover Cluster if you:

• Have Windows Enterprise or Datacenter
• Have shared block storage (iSCSI or FC or equivalent)

This provides a proper failover configuration where the entire config goes from one server to another, and you can have more than 2 servers in your failover pool.