Connection Timout Problem

A handful of people have reported ongoing problems with their ssh sessions timing out when left idle for a short time. Turning off the power save features on the machines seems to have resolved the problem for quite a few people. However, Simpatico seems particularly aggressive about killing stalled connections and users will have to resort to using the keep-alive option to keep from being disconnected.

Turning on Keep Alive: When conecting to CSLab using ssh include the following options, -o ServerAliveInterval=120 -o ServerAliveCountMax=3. This means your command should look something like:

ssh -o ServerAliveInterval=120 -o ServerAliveCountMax=3 username@cs.toronto.edu

You can play around with the numbers if it doesn't solve the proble. Try lowering the alive interval to 60 or if there is a lot of nios try increasing the max count to 5. Once you find a setting that works you can add it as an alias so that you won't have to keep retyping it.

Turning off Power Save (OS X): To turn the power save option on OS X off, go to System Preferences, then in the Hardware section go to Energy Saver. You probably don't want to turn power save off when disconnected so for Settings select Power Adapter, then under "Put the computer tp sleep when it is inactive for:" move the slider all the way to the right so that it points to never. Now the computer will not go to sleep when it its plugged in.