General

Relevant to NDFC DHCP deployments

Symptom

The customer may have an environment which requires DHCP over VXLAN, and therefore a source loopback is required to ensure proper definition of the relay IP for the remote DHCP server. In environments which are dual stack, this will likely require the definition of multiple servers for the different address families. However, after adding more than two servers, the customer may find that the source loopback configuration for one of the address families is being removed, which could cause an outage if deployed.

Conditions

- Running NDFC 12.1(3b) with custom template for DHCPv6 relay or 12.2(1) and later with the updated template to allow for DHCPv6 relay - Have a dual stack environment which uses both IPv4 and IPv6 DHCP servers - Already have a DHCPv4 server and DHCPv6 server defined for a given network/SVI (total of two DHCP servers on the network/SVI) - Have a source loopback configured - Attempt to apply an additional IPv6 or IPv4 server

Workaround

None

Further Problem Description