when I use either of ssh -CX -L 10443:172.20.0.1:443 <hostname> ssh -4CX -L 10443:172.20.0.1:443 <hostname> where <hostname> has both a functioning A and AAAA record, I can connect and use the port forward. However, if I use: ssh -6CX -L 10443:172.20.0.1:443 <hostname> I can't connect to the tunnel because seemingly the -6 prevents use of an IPv4 address in any context. I had imagined the -4 and -6 were there to dictate what way ssh connects only. Apparently that was a misreading on my part but it would be preferable to be able to separate the preference for an IPv4/v6 ssh connection from the IP version used in any forwarded connections.
This is working as intended. The documentation for -4/-6 say that they force ssh to use only IPv4/IPv6 addresses and that is what it is doing. These options are big hammers that are mostly intended for debugging as a crutch when the network is broken.
Move resolved bugs -> CLOSED after 8.0 release