Symptom

When configuring IPv6 address on a sub-interface on a Firepower Threat Defense Cluster using REST API, you can set the auto config option to "True" on the request body. However, since Firepower Threat Defense devices in a cluster configuration does not support auto config option for IPv6 addresses, this may result in deployment failures.

Conditions

This will happen only when configuring the interfaces using a REST client. The FMC UI does not support that option

Workaround

Through REST API set auto-config to false for that interface. (or) Delete the interfaces from the Client or using the FMC UI. Reconfigure the interfaces with the auto config option set to False

Further Problem Description