Where to look if X11 forwarding does not work
1. In /etc/ssh/sshd_config should be the options:
AddressFamily inet (if the host is ipv4 only)
2. in /etc/hosts shold be
127.0.0.1 localhost (if the host is ipv4 only)
3. try debugging ssh session:
/usr/sbin/sshd -d -p 222
4. DISPLAY environment variable should be set up by default after connecting to the ssh server.