1
vote
2answers
95 views

can I tell to useradd to execute a script? Maybe in /etc/default/useradd?

There are plenty of people that already answered to the question "how to execute useradd properly in a script?" My question is: "is it possible to tell to useradd to execute one script when it is ...
20
votes
1answer
23k views

How does tcp-keepalive work in ssh?

I am trying to code a shell-script that uses a ssh-connection for doing "heartbeats". I want to terminate the client- and server-side of that connection after a certain timeout (after the connection ...
1
vote
4answers
1k views

How to find which machines are idle on a cluster of many nodes

I run measurements on a cluster consisting of 32 nodes/machines. I do not require all nodes, only 4, for example. The problem is most of the time, the nodes are busy with other people running their ...