Phil Dawes’ Stuff

Uncovered an awesome ssh trick today. At work we use ssh extensively to run stuff on remote unix and windows servers, using SSH agents to handle batch job authentication. That’s all sweet because on unix you don’t need to install client software on each box, and you don’t need a root account - just copy a public key and you’re good to go. In a big multi-national company not installing stuff means less bureaucracy, and that counts for a lot.

Now unbeknown to me it appears that on top of all that good stuff you can also multiplex ssh sessions over existing connections using just vanilla openssh 4. This is tres-bien-cool for a couple of reasons:

1) Connection times are massively reduced. Like a few milliseconds rather than a couple of seconds.

2) Lots of connections to the same account only consume a single tcp connection and don’t load the cpu with handshakes.

OMG! Surely this makes ssh the killer app for a whole slew of things: monitoring remote processes, interactive remote applications, infact anything that you’d previously have installed client software for. Now why isn’t there a tool industry built around this awesome protocol?