emacs:open file through ssh failed

Question

When trying to open a file through ssh in emacs, I got an error:

Couldn't find a POSIX `id' command

QUESTION: What is the problem?

Answer 1

Does your remote system has proper id command? You can verify what TRAMP is trying to do if you set

(setq tramp-verbose 10) 

Then try to connect and monitor buffers *tramp/...* and *debug tramp/...* . If the remote path does not get set correctly by TRAMP, you can change it:

(add-to-list 'tramp-remote-path "/path/to/id/command")

Answer 2

This just happened to me recently for the first time... after never having the issue before on the same cluster of servers. It ended up being that the server I was trying to connect to was out of disk space...and this error was just a side effect of that. So it's worth doing a df -h if this issue seems to come out of nowhere.