I've recently taken over a network that has Windows DHCP running on the domain controllers in failover mode, and I want to shift the DHCP service off of them. My plan is to set up two new DHCP servers configured for failover and migrate the existing scopes. Then, I'll update the relay addresses since the clients send lease requests via relays and not directly to the servers. Considering we have over 100 scopes, I know I can't do this all at once. Is there any risk involved in this migration process? I'm a bit anxious that something might go wrong, so any tips would be appreciated!
4 Answers
Migrating the Windows DHCP roles is actually pretty simple. You just need to use PowerShell to back up the scopes and leases onto the new primary server. After this, enable failover for each scope. Don’t forget to update your relay forwarding IPs! **Also, use -verbose in your commands to track the process**. By the way, it’s a good idea to disable the DHCP service on the old servers for safety until you’re sure everything’s working!
Honestly, if something goes awry, you can always just switch back to the old servers. Follow the guidelines on the Microsoft website for migrating DHCP, and don’t remove the old servers until you're sure the new ones are fully operational. But really, what’s the rush to move it? DHCP works fine on DCs with low overhead!
To simplify, just add the two new servers for failover, wait for replication to complete, then disconnect the old ones and shut down their services. But remember, Microsoft DHCP failover only supports two servers, so keep that in mind.
Before making any changes, consider lowering the lease time to speed up the transition to the new servers. It can help with client updates during the migration.
You don't have to lower the lease time; PowerShell commands can help you export and transfer existing leases smoothly.
If you encounter any errors when importing, feel free to share here. I've got experience with this!