ipv6,sit0, and sshd

[jgeorgeson]

So after installing and booting FC2-test1, I see that the ipv6 module is loaded, and in use so I can't unload it. Running `ip link` shows an interface sit0, which I believe is an ipv4/ipv6 tunnel. Running `netstat -lntp` shows sshd bound to :::22. So What I think is happening, is sshd is default configured to bind to the ipv6 IPADDR_ANY and the sit0 interface is there so ipv4 machines can connect to it. This seems awfully stupid to me. I don't have an ipv6 address, I don't want an ipv6 interface, and I don't want to add the extra step of mapping from ipv4 to ipv6 for sshd 'just because it can.' Can anyone comment on my assumptions, and if they are right, how to get sshd on plain ipv4 0.0.0.0:22 and get rid of ipv6/sit0.

[mhelios]

I'm interested to know how this all works also. There's a significant lack of documentation on the subject at this point.
sit0 is an IPv6-to-IPv4 tunnel. Why IPv6 is enabled as default is beyond me, except for the notable fact that The Fedora Project is where the latest technologies are tried. As for returning sshd functionality to IPv4, I'm not sure.
There is a thread on using ssh with IPv6 on the fedora mailing list you may want to look at:
http://www.redhat.com/archives/fedor.../msg02654.html

[mhelios]

Well, I was tinkering with the SSHd configuration and have found the solution:
In /etc/ssh/sshd_config:

Uncomment "ListenAddress 0.0.0.0".

Then simply
`service sshd restart`

And voila:

tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN