slow ssh login to a remote machine

On the RHEL machine, try:

ssh -o GSSAPIAuthentication=no [email protected]

If that works, make it permanent by editing ~/.ssh/config and add:

GSSAPIAuthentication no

Also, check that the RHEL is visible in DNS (from the server's point of view). The server tries to check your reverse DNS resolution. If that fails, you'll suffer a delay.

This check can be disabled:

Edit /etc/ssh/sshd_config

OpenSSH: Use UseDNS no

Solaris: Use LookupClientHostnames no

Restart sshd and it should be quicker to log on.