dhcp failover

Question

Hello,

We currently have a DHCP failover construction from server A to server B.
The IP helper for DHCP is configured on a lot of places so we would like to keep the existing IP of server B so we dont need to change the helpers everywhere.

The plan i have is to build a new server C. Remove the Hot-standby failover construction from server A --> server B. Then build a new failover construction from server A --> server C. And add the IP of server B as a second IP to server C.

Will this construction work? Will the clients be serviced with DHCP when they request an IP from the old IP of server B? Do i need to re-authorize the DHCP server C?

Thanks!

LEVD

Answer 1

Dear Van,

Yes, your plan will work.

Here's a breakdown of why and what you need to consider:

• Adding Server B's IP to Server C: You can add the IP address of Server B as a secondary IP address to Server C's network interface. Windows Server supports multiple IP addresses on a single network adapter. This is crucial because your IP helpers are pointing to Server B's IP.
• Client Servicing: When clients request an IP from the old IP of Server B (which is now a secondary IP on Server C), Server C will receive the DHCP request. Since Server C will be part of the new failover relationship with Server A and will have the necessary scopes configured (which will be replicated from Server A), it will be able to service those requests.
• Re-authorization of Server C: Yes, you will need to authorize the DHCP server role on Server C in Active Directory. A DHCP server must be authorized to start servicing clients on the network

Best Regards,