[ubuntu] SSH Slow to Prompt for password : If you're using host names (e.g., "ssh host.example.com") then you must have proper forward and reverse DNS resolution at both ends. There are ways to avoid this: 1) Add "UseDNS no" to /etc/ssh/sshd_config on the server and /etc/ssh/ssh_config on the client; or 2) Set up a DNS server with proper forward and reverse ("in-addr.arpa") records for both the client and server; or 3) Create entries in the hosts file on both the client and server with the appropriate names and addresses; or 4) Use IP addresses rather than names.