This was happening on 26.1.x and continues on 26.7.1. I'm on AT&T fiber and using an AZORES WAS-110 fiber module/ONT to bypass the AT&T provided gateway. For this to work, my `ixl0` interface uses DHCP/DHCPv6 to get IP addresses and I create a virtual IP (192.168.11.10/24) on `ixl0` in order to manage the WAS-110 module.
The problem is that for whatever reason, getting an IP address from AT&T is _slow_. After rebooting the firewall, I often have to login and manually run `dhclient ixl0` to force it to try again and that works. Once an IPv4 address is obtained, DHCPv6 seems to happen automatically.
The problem is that the system seems to not really register that an IPv4 address has been obtained and so NAT is broken- running `tcpdump -ni ixl0` shows traffic egressing with a source IP of 192.168.11.10- not the public IP that AT&T has given via DHCP. I've figured out that I can fix this by going into the interface config setting and re-applying the existing settings, but this sucks.
Seems like the root cause of the issue is AT&T being slow to give out an IP address over DHCP- any way to make things more robust?
Meant to mention that for outbound NAT I'm using "Manual outbound NAT rule generation" and selecting NAT Address: "interface address"