Problem scenario
You are trying to use SSH, but you get a "connection timed out" error. What should you do?
Possible solution #1
Can you try to ping the hostname or IP address? Are you connected to a necessary VPN? Perhaps the endpoint is down or not reachable from the network you are on.
Possible solution #2
Is there a router that was recently configured? Has a firewall rule been turned on? Is there an email about such a maintenance window or configuration change that you forgot about? Can you use the nmap command to see if port 22 is open to the destination?
Possible solution #3
Run the command again with the -v flag. This will provide more verbose output to show the underlying problem.