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Ahmed Musallam
Ahmed Musallam

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How To Autocomplete SSH Hosts

So you know about SSH config file, there are several awesome articles on the subject:

This awesome article

and this one that covers some tips and tricks

Now, with all of that, you still have to remember the full host entry to connect and it will not be autocompleted for you.

let's say I have the following in my config file:


Host unicorn-one
  HostName 1.2.3.4
  User amusallam
  IdentityFile ~/.ssh/id_rsa

Host unicorn-two
  HostName 2.2.3.4
  User amusallam
  IdentityFile ~/.ssh/id_rsa

Host unicorn-three
  HostName 3.2.3.4
  User amusallam
  IdentityFile ~/.ssh/id_rsa

and now I type ssh unicorn into terminal and hit ⇥ Tab, it will not auto complete...

sad gif

But fear not! for I have what your heart desires!

Autocomplete Script

I've only tried this on MacOs.

courtesy of this stackexchange answer:

Found it!!

It seems that in Ubuntu the entries in ~/.ssh/known_hosts are hashed, so SSH completion cannot read them. This is a feature, not a bug. Even by adding HashKnownHosts no to ~/.ssh/config and /etc/ssh/ssh_config I was unable to prevent the host hashing.

However, the hosts that I am…

add the following file: /etc/bash_completion.d/ssh whose contents:

_ssh() 
{
    local cur prev opts
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"
    opts=$(grep '^Host' ~/.ssh/config ~/.ssh/config.d/* 2>/dev/null | grep -v '[?*]' | cut -d ' ' -f 2-)

    COMPREPLY=( $(compgen -W "$opts" -- ${cur}) )
    return 0
}
complete -F _ssh ssh

Then load that file: in your ~/.bash_profile, add:

## load ssh autocompletion
. /etc/bash_completion.d/ssh

and reload by running source ~/.bash_profile or just terminate your terminal and reopen it.

and voila!

(The flashes you see below are me hitting ⇥ Tab)

Alt Text

easy peasy!

Extra helpful alias

if you want to see a list of all your hosts, you can add this alias to your .bash_profile:

# list all "Host" and "HostName" lines, then remove the strings: "Host " and "HostName "
alias sshhosts="grep -w -i -E 'Host|HostName' ~/.ssh/config | sed 's/Host //' | sed 's/HostName //'"

reload by running source ~/.bash_profile or just terminate your terminal and reopen it.

then you can run it:

sshhosts

from unicorn example above, this prints:

unicorn-one
  1.2.3.4
unicorn-two
  2.2.3.4
unicorn-three
  3.2.3.4

Top comments (2)

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tobiashochguertel profile image
Tobias Hochgürtel

The "Extra helpful alias" isn't useful when you have your ssh config stored in several config files. As example, I have a few ssh-config files with host definitions stored under ~/.ssh/config.d/and my ~/.ssh/config has just one line to include all config files from the sub-folder config.d/.

My ~/ssh/config has only one line:

Include config.d/*.config
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and the directory: config.d/ has the following files:

~/.ssh/config.d/1-homeoffice.config
~/.ssh/config.d/2-github.com.config
...
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Quick solution for fixing the "extra Helpful alias is to use the $opt-variable-command from the bash-completeion:

alias sshhosts="grep '^Host' ~/.ssh/config ~/.ssh/config.d/* 2>/dev/null | grep -v '[?*]' | cut -d ' ' -f 2-"
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okay it prints then only the Host description, without their ip-address / hostname value. But it lists all definitions from all my ssh-config files.

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vgrs profile image
Vugar Suleymanov

Also it is good to add complete -F _ssh scp to the end of /etc/bash_completion.d/ssh file, to enable autocompletion in scp command.. Thank you for helpful article

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