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In case you prefer a password protected key or you want to "hop" from system to system, SSH Agent Forwarding is helpful.

Bash aliases for convenience

Bash aliases of ssh commands for most of the Blue Light supported computers are in the Blue Light git as "bash library/aliases.BL.sh" and functions.BL.sh.  They are intended for sourcing from .bashrc or similar.  Once they have been sourced the ag function can be used to display aliases containing an arbitrary string (ag is short for alias | grep).  The aliases have been designed with that in mind so they include nickname and user name strings.

An example showing user names:

master c@CW8:~$ ag work
1) uma='ssh root@ac002.workcom.av'
2) valli='ssh root@ac001.workcom.av'
#?

Where necessary the aliases hop via an intermediate host (Blue Light policy is to configure Internet-exposed servers to accept root logon only from specific addresses):

c@CW8:~$ ag hot
1) rad='ssh -A -t root@blav.bluelightav.org ssh root@hotspot.bluelightav.org'
#?

An example showing a hosting service provider name:

c@CW8:~$ ag online
1) online.net='ssh -A root@sd-44498.dedibox.fr'
2) online.net.backup='ssh -p 2222 root@sd-44498.dedibox.fr'
#?

Problem analysis

The ~/.ssh directories must have 700 permissions, for example:

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