ControlMaster in OpenSSH – speeding up editing files remotely with emacs + tramp

Mac OS X

Vinh Nguyen


June 17, 2010

So I was googling around to find out how to change the shell in tramp for emacs, and I ran into this and this.

When editing remote files with emacs using tramp, opening and saving files can take a bit of time, due to re-logging in and authenticating. I discovered that you OpenSSH has a feature that allows one to re-use an existing connection to a remote host when opening new connections to that host. This is quite cool. Place the folling in ~/.ssh/config:

Host *
ControlMaster auto
ControlPath ~/.ssh/master-%r@%h:%p