Re: Tramp and ssh control path

[Suvayu Ali]

Hi Michael,

On Mon, Apr 15, 2013 at 03:39:30PM +0200, Michael Albinus wrote:
> Michael Albinus <michael.albinus@gmx.de> writes:
> 
> >> BTW, such problems shouldn't exist any more now that the master
> >> is handled correctly (it's not one of the sessions any more, so all
> >> sessions are "equal").
> >
> > In this case, I could make ControlPath configurable, with a red blinking
> > warning about possible side effects ...
> 
> The Tramp FAQ has now the following wording:
> 
> --8<---------------cut here---------------start------------->8---
>    * TRAMP does not use my 'ssh' 'ControlPath'
> 
>      Your 'ControlPath' setting will be overwritten by 'ssh' sessions
>      initiated by TRAMP.  This is because a master session, initiated
>      outside Emacs, could be closed, which would stall all other 'ssh'
>      sessions for that host inside Emacs.
> 
>      Consequently, if you connect to a remote host via TRAMP, you might
>      be prompted for a password again, even if you have established
>      already an 'ssh' connection to that host.  Further TRAMP
>      connections to that host, for example in order to run a process on
>      that host, will reuse that initial 'ssh' connection.
> 
>      If you know that your 'ControlPath' settings won't disturb TRAMP,
>      you could customize the variable 'tramp-ssh-controlmaster-options'
>      like this:
> 
>           (setq tramp-ssh-controlmaster-options
>                 (concat
>                   "-o ControlPath=/tmp/ssh-ControlPath-%%r@%%h:%%p "
>                   "-o ControlMaster=auto -o ControlPersist=no"))
> 
>      Note, that "%r", "%h" and "%p" must be encoded as "%%r", "%%h" and
>      "%%p", respectively.
> --8<---------------cut here---------------end--------------->8---
> 
> This shall work starting Tramp 2.2.7. Emacs 24.3 has built-in Tramp
> 2.2.6, so it doesn't work there yet.

Thanks a lot, for both the very clear FAQ and the option to override it.

Cheers,

:)

-- 
Suvayu

Open source is the future. It sets us free.