How to extract an ova file

In Windows, you can use something like 7-zip to extract an ova file. In Linux, you can just untar it

mv something.ova . something.tgz
tar xvf something.tgz

Close an unresponsive ssh session with ~.

SSH 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