implementing a heartbeat for tramp

implementing a heartbeat for tramp

[Matthew Kennedy]

A router I have to work through frequently seems to kill inactive ssh
sessions after a few minutes for no apparent reason.  If I'm using
tramp with one of the ssh or scp methods, then this means my tramp
connection is killed, causing tramp to reconnect automatically and go
though its time-consuming initialization phase.

Based on my very effective hack where I run "xclock -update 10" to
cause some activity on the connection every 10 seconds during remote
shell sessions, I thought I might attempt something similar with
tramp... call it a "tramp heart-beat" if you will.

My idea was to create a timer, which walked all emacs buffers looking
for tramp buffers.  When it found one, it would (maybe)
`tramp-send-command' to send a heart-beat (I guess some kind of null
operation... touch /dev/null??? -- or maybe the command itself
suffices)

Does this sound reasonable?  Any other ways to approach this problem
perhaps?

Matt
-- 
Matthew Kennedy

Re: implementing a heartbeat for tramp

[Dan Anderson]

> Does this sound reasonable?  Any other ways to approach this problem
> perhaps?

There's a LISP function to alias a command for another command.  So you
could alias tramp so that whenever it starts in a buffer it would work
on a timer.  Not sure of what it is though... :-(

-Dan

Re: implementing a heartbeat for tramp

[Kai Grossjohann]

Matthew Kennedy <mkennedy@gentoo.org> writes:

> My idea was to create a timer, which walked all emacs buffers looking
> for tramp buffers.  When it found one, it would (maybe)
> `tramp-send-command' to send a heart-beat (I guess some kind of null
> operation... touch /dev/null??? -- or maybe the command itself
> suffices)

I think "echo heart-beat" would do fine :-)
Or maybe "echo hello", that's used in Tramp for other purposes
already, I think.

But maybe someone can come up with a really KEWL command that goes
well with the name Tramp?

Are you going to contribute your code?  That would be just great.

Hm.  Hmmm...  Isn't there a keep-alive option for ssh?  Just a
thought.

Kai

Re: implementing a heartbeat for tramp

[Matthew Kennedy]

Kai Grossjohann <kai@emptydomain.de> writes:

> Matthew Kennedy <mkennedy@gentoo.org> writes:

[...]

> I think "echo heart-beat" would do fine :-)
> Or maybe "echo hello", that's used in Tramp for other purposes
> already, I think.
>
> But maybe someone can come up with a really KEWL command that goes
> well with the name Tramp?
>
> Are you going to contribute your code?  That would be just great.
>
> Hm.  Hmmm...  Isn't there a keep-alive option for ssh?  Just a
> thought.

[...]

Hi Kai,

Yes, I will try to write it in such a way that its contributable ;)

There is a keep alive option for ssh, unfortunately this router
somehow clobbers it.

Matt
-- 
Matthew Kennedy