Bashing Linux   Linux system administration, programming and everything that goes in between…

I personally have a numerous number of hosts which I sometimes have to SSH to. It can get rather confusing and inefficient if you get lost among them.

I’m going to show you here how you can get your SSHing to be heaps more efficient with just 5 minutes of your time.

.ssh/config

In $HOME/.ssh/config I usually store all my hosts in such a way:

Host host1
    Port 1234
    User root
    HostName host1.potentially.very.long.domain.name.com

Host host2
    Port 5678
    User root
    HostName host2.potentially.very.long.domain.name.com

Host host3
    Port 9012
    User root
    HostName host3.potentially.very.long.domain.name.com

You obviously got the idea. So if I’d like to ssh to host2, all I have to do is:

ssh host2

That will ssh to root@host2.potentially.very.long.domain.name.com:5678 – saves a bit of time.

I usually manage all of my hosts in that file. Makes life simpler, even use git if you feel like it…

Auto complete

I’ve added to my .bashrc the following:

_ssh_hosts() {
    local cur="${COMP_WORDS[COMP_CWORD]}"
    COMPREPLY=()
    local ssh_hosts=`grep ^Host ~/.ssh/config | cut -d' ' -f2 | xargs`
    [[ ! ${cur} == -* ]] && COMPREPLY=( $(compgen -W "${ssh_hosts}" -- ${cur}) )
}

complete -o bashdefault -o default -o nospace -F _ssh_hosts ssh 2>/dev/null \
    || complete -o default -o nospace -F _ssh_hosts ssh
complete -o bashdefault -o default -o nospace -F _ssh_hosts scp 2>/dev/null \
    || complete -o default -o nospace -F _ssh_hosts scp

Sweet. All that you have to do now is:

$ ssh TAB TAB
host1 host2 host3

We are a bit more efficient today.