I had been troubleshooting the following error message when trying to add an IPv6 BGP peer to my PA:
For some reason our configuration had IPv6 configured on all interfaces of the firewall but only the Trust interface had the checkbox checked for "Enable IPv6 on the interface". The ISP uplink interfaces still needed the checkbox for Enable IPv6.
Since there was nothing in the Knowledge Base showing up while troubleshooting this error, I thought I would add this information. I find it odd that this checkbox exists but as I recall Palo Alto added it to prevent unintentional security risks with your internal IP's being Internet routable.