Use `known-hosts-files` for `zsh` ssh command completion

Andreas

6/25/24, 9:17 PM

This question was originally asked on SO, which is incorrect. As I was not able to (get it) moved to serverfault, I am re-asking it.

I am trying to configure tab completion for the ssh command in zsh to use an additional known_hosts file (which not located in ~/.ssh). By additional I mean I still want to use the "default" known_hosts file.

Currently, when I hit TAB after ssh, I get a list of hosts which seems to come from ~/.ssh/known_hosts and (probably) /etc/hosts. I would like to also get the hosts listed in ~/other/path/known_hosts.

I found a lot of material online, but somehow I cannot wrap my head around this one. The zsh webiste for example lists a style called known-hosts-files which sounds very promising. Also when I see how it is used it seems quite to the point.

But I cannot figure out how to use known-hosts-files.

I tried, for example, the following in my .zshrc:

zstyle ':completion:*:*:ssh:*:*' known-hosts-files '~/other/path/known_hosts'

and many variations of it to no avail.

For good measure I have also added (in my .zshrc):

zstyle ":completion:*:commands" rehash 1

but this did not change anything.

There is an older answer here on serverfault and another answer) tackling the same question, but I do not fully understand them and it seems that known-hosts-files should do exactly what I want?

I also use Oh-my-zsh, if that matters...

1 + 0

zsh

mac-osx

Score:0

Server

Andreas

6/28/24, 5:43 AM

Well, finally I found the culprit: quotes.

When setting known-hosts-files to just a single file (like in my example), the quotes can be used, but not with ~!

Adding this to .zshrc works as intended (macOS):

zstyle ':completion:*:*:ssh:*:*' known-hosts-files 'Users/<username>/other/path/known_hosts'

In hindsight it seems reasonable: to set known-hosts-files to a list of files, do not use quotes at all (~ is then OK to use again).

So the following works:

zstyle ':completion:*:*:ssh:*:*' known-hosts-files /etc/ssh/ssh_known_hosts ~/.ssh/known_hosts ~/other/path/known_hosts

This seems to be related to the fact that the shell is interpreting the quoted text as a literal single string... Naturally...

+ 0

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Use `known-hosts-files` for `zsh` ssh command completion

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