How to terminate or cancel an unresponsive ssh session.
While connected to a remote host through an ssh connection using Putty or other ssh clients, your client might freeze and not respond to any keyboard activity. In order to force an exit, there is a “secret” keyboard shortcut – Enter~. [ Enter followed by ~ followed by .(dot) ]
[daniel@kauai ~]$ ssh daniel@linuxfreelancer.com Hostname..........: svm1010.xenvps-server.net Uptime............: 21:25:34 up 14654 days, 15:00, 2 users, load average: 0.09, 0.19, 0.17 Server IP.........: 173.230.241.181 Operating System..: Ubuntu 10.04.4 LTS Username..........: daniel daniel@svm1010:~$ uname Linux ***Press*** Enter~. {Enter key, followed by '~', followed by '.'} daniel@svm1010:~$ Connection to linuxfreelancer.com closed. [daniel@kauai ~]$
After you press the Enter~. the connection will be aborted and your session will return to the connection originating client shell.
Alternatively, you can background the ssh session with Enter~Ctrl+Z and then foreground it with fg command.
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