VMC DHCP relay configuration changes do not take affect

Products

• VMware Cloud on AWS

Issue/Introduction

Symptoms:

• After initial DHCP configuration no further changes to target DHCP servers take affect
• Though the UI shows the correct IP for the DHCP relay requests, the requests continue to go to a previously configured DHCP server

Resolution

SDDC version M9/ M10:

 

1. Network Administrator will need to change the segment Type to “disconnect”  all the network segments with DHCP during maintenance window
2. Change the DHCP server details in  “DHCP relay” section.
3. Change network segments type back to  “Routed”
4. On guest VM’s, DHCP release/renew will need to be performed to update the IP lease with the newer DHCP servers.

 

SDDC version M8 and earlier: 

1. Disconnect all the VM’s network interface attached to the DHCP logical networks
2. Delete the logical networks
3. Make changes to DHCP relay config with new DHCP Server address
4. Recreate DHCP logical networks and attach their VM’s

 

Workaround:
In use cases where the environment cannot take the downtime to update the DHCP server please contact VMware support to discuss possible workarounds.