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How to kill an unresponsive SSH session.md

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+# How to kill an unresponsive SSH session
+
+## Summary
+
+Lets say you're happily typing in your remote shell when all of sudden, the crappy Wi-Fi network you're using goes down.
+You end up with a perfectly unusable frozen shell, ugh!
+
+To do that, assuming you lost connectivity, press in that order:
+
+```shell
+[Enter]
+~
+.
+```
+
+That is, **return** key then **tilde** then **period**.
+
+This will send an escape sequence to your local SSH client and terminate the connection.
+So this will always work even without a network connection.
+
+Here's the list of escape sequences:
+
+Supported escape sequences:
+
+`~.`  - terminate connection (and any multiplexed sessions)
+`~B`  - send a BREAK to the remote system
+`~C`  - open a command line
+`~R`  - Request rekey (SSH protocol 2 only)
+`~^Z` - suspend ssh
+`~#`  - list forwarded connections
+`~&`  - background ssh (when waiting for connections to terminate)
+`~?`  - this message
+`~~`  - send the escape character by typing it twice
+
+
+(Note that escapes are only recognized immediately after newline.)