GitLab

Previously, we have not provided users with an easy way to do passwordless ssh (particularly from startup scripts) between nodes in their experiments.

This is becoming problematic, as many popular software stacks (eg. hadoop, openstack, chef) want to do this. Users are rolling their own ways of doing it, doing so badly, and getting broken into as a result.

We have considered three possibilities so far:

1. Set this up for the root user only: straightfoward to do, but encourages users to use root account and they may not find it easily
2. Set up for each individual user account: Tricky to do due to having many user accounts, and very problematic with NFS home directories
3. Use an shosts type mechanism to capture all accounts: appealing, but might force us to bite the bullet of per-host ssh keys in order to do it securely