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Enable tab completion for known SSH hosts

Terminal - Enable tab completion for known SSH hosts
complete -W "$(echo `cat ~/.ssh/known_hosts | cut -f 1 -d ' ' | sed -e s/,.*//g | uniq | grep -v "\["`;)" ssh
2011-06-01 23:21:06
User: sammcj
-2
Up
Down
Enable tab completion for known SSH hosts
Add to favourites | Report as malicious

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
complete -W "$(echo $(grep '^ssh ' .bash_history | sort -u | sed 's/^ssh //'))" ssh
2009-07-25 23:07:25
User: 0x89
9
Up
Down
ssh autocomplete

Stop tormenting the poor animal cat. See http://sial.org/howto/shell/useless-cat/.

Edit:

replaced

sort | uniq

by

sort -u
Comments (2) | Add to favourites | Report as malicious
complete -W "$(echo `cat ~/.ssh/known_hosts | cut -f 1 -d ' ' | sed -e s/,.*//g | uniq | grep -v "\["`;)" ssh
2009-07-23 15:59:55
User: viner
3
Up
Down
ssh autocomplete

Add to your bash profile to minimize carpal tunnel syndrome.

Doesn't work with user@hostname but appending "-l user" works fine if needed.

Works for ping as well..

complete -W "$(echo `cat ~/.ssh/known_hosts | cut -f 1 -d ' ' | sed -e s/,.*//g | uniq | grep -v "\["`;)" ping

Show sample output | Comments (4) | Add to favourites | Report as malicious
perl -ne 'print "$1 " if /^Host (.+)$/' ~/.ssh/config
2011-08-21 14:51:20
User: bashrc
Functions: perl
3
Up
Down
ssh autocomplete based on ~/.ssh/config

I use this in my bashrc to expand hosts defined in ~/.ssh/config:

function _ssh_completion() {

perl -ne 'print "$1 " if /^Host (.+)$/' ~/.ssh/config

}

complete -W "$(_ssh_completion)" ssh

Here's a great article on how to setup your own ~/.ssh/config:

http://blogs.perl.org/users/smylers/2011/08/ssh-productivity-tips.html

Comments (1) | Add to favourites | Report as malicious
complete -W "$(sed 's/;.*//;' /etc/hosts | awk ' /^[[:digit:]]/ {$1 = "";print tolower($0)}')" ssh
2011-06-20 03:54:45
User: daodennis
Tags: ssh bashrc tab completion /etc/hosts
-1
Up
Down
Enable tab completion for known SSH hosts

If you have a lot of hosts in /etc/hosts this would be very useful. Anyone have any more concise examples?

Comments (0) | Add to favourites | Report as malicious
complete -W "$(while IFS=' ,' read host t; do echo $host; done < ~/.ssh/known_hosts)" ssh
2011-02-10 03:34:35
User: smax
-2
Up
Down
ssh autocomplete

Simple and fast variant, not using external programs. Another variation:

complete -W "$(while read line; do echo ${line%%[, ]*}; done < ~/.ssh/known_hosts)" ssh

HashKnownHosts must be off, of course.

Comments (0) | Add to favourites | Report as malicious

Know a better way?

If you can do better, submit your command here.

What others think

Useful. But we can make it better.

Lose the "cat" and pipe the file straight into sed.

Use "sed" to delete everything after a comma or a space (no need for cut).

Then use "sort -u" to remove duplicates. "uniq" will only work if the list is already sorted.

I've dropped your final "grep" -- I'm sorry, I don't understand it. When do you see "[" in your hostnames?

complete -W "$(echo $(sed 's/[, ].*//' < ~/.ssh/known_hosts | sort -u))" ssh
Comment by flatcap 102 weeks and 6 days ago

But your command and my improvement are static -- the list of hostnames is only read once.

What you really need is something that reads known_hosts every time.

Then, if you ssh to a new host, the name is added to known_hosts and the completion automatically picks it up.

This function does the trick. It's not a one-liner any more :-)

_ssh_complete () { local cur _get_comp_words_by_ref cur COMPREPLY=( $( compgen -W "$(echo $(sed 's/[, ].*//' < ~/.ssh/known_hosts | sort -u))" -- "$cur" ) ) } complete -F _ssh_complete ssh
Comment by flatcap 102 weeks and 6 days ago

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