Re: tramp (2.2.7); tramp does not distinguish connections differentiated by port number

[Michael Albinus]

Tzvi Edelman <address@hidden> writes:

> Hi Tramp-Devel,

Hi Tzvi,

> When I attempt to use tramp in the same emacs session to connect to
> different hosts sitting behind a single router (distinguished by
> different port numbers), I only get files from the host to which I
> first connected via that router in that session.

This is known. In the Tramp sources, there is a comment

;; Check for port number.  Until now, there's no
;; need for handling like method, user, host.

I should change the wording of "Until now", at least ...

> Perhaps a clue to the cause of this bug can be seen in the name of
> buffer "*tramp/ssh address@hidden" used for both connections;
> it does not include a port# in the buffer name.

Unfortunately, it is not such easy. Tramp uses a vector for internal
connection identification with the slots [method user host localname hop].

Adding a port slot to this vector is possible, but it requires a check
over the whole sources, whether it breaks something.

I'll add an entry to the TODO list. If time permits, I'll check. But
don't start to cheer yet.

> Yes, I can construct workarounds to circumvent this bug, but I'd much
> rather that Tramp deal with this correctly and not treat all
> connections to the same hostname as the same when they have different
> port numbers.
>
> I attach the data created by tramp-bug as tramp-bug.txt and the buffer
> as address@hidden

Personally, I would add different entries to ~/.ssh/config, call them
"vcon30", "vcon32", or so. Then you could connect via "/ssh:vcon30:",
which is much shorter than "/ssh:address@hidden:".

> Thanks - Tzvi.

Best regards, Michael.