Master/node to gather and graph "everything" on your systems using Tobi Oetiker's rrdtool. It can optionally warn your surveillance software. This software package was originally called LRRD. The project. Please see http://munin-monitoring.org/
chainssh is a shell script to smplify the ssh login via multiple sshgateways/firewallgateaways. e.g. connect from homehost via sshgateway to a clusternode with one command.