BGW210-700 port forwarding: There can be only one!

[taa_sonic]

After investigating some odd behavior from Apple Mail on my wife's Macs, it looks to me like port-forwarding (using the NAT/Gaming controls) on AT&T's Arris gateway only allows one connection at a time to be forwarded. Has anyone else seen this, or found a good workaround?

FYI, the behavior seems to be that if you forward a port (the first problem I saw involved IMAPS on 993) then the gateway forwards to the same port (993) on the destination machine, as it should. However, it will only use the same port number (993) as the source port on the gateway, which means only one client can be connected at a time. If more than one client attempts a connection, all but the first time out. I verified this using HTTPS and SSH ports as well as IMAPS.

[taa_sonic]

Brief followup on this.

Oddly, the gateway "does the right thing" with connections that originate on the WAN. It's only connections to the WAN address that originate from the LAN that are limited to one. There's definitely some routing magic going on here that I don't understand.

I've worked around my particular problem by running a port forwarder on another host where I have access. It's an ugly kluge, but it's good enough for now.