External IP and strange ports

From @Mossfeldt on Fri Feb 24 2017 16:45:36 GMT+0000 (UTC)

When doing ipfs id on one of my nodes behind pfSense firewall i get alot of different ports on my external IP(v4). Why is that?
The node is on standard port and port is forwarded in firewall.

Copied from original issue: https://github.com/ipfs/faq/issues/228

From @mitar on Tue Mar 21 2017 10:12:11 GMT+0000 (UTC)

Related: https://github.com/ipfs/go-ipfs/issues/3780