ssh over udp (or: -L option listening for traffic with a UDP service?)

Ángel González keisial at
Thu Oct 11 10:23:06 EST 2012

On 10/10/12 23:19, Peter Stuge wrote:
>> I see the '-L' option to ssh, so it looks like that's a hook to do this,
>> but AFAICT, the listening port is TCP and TCP only. Is it possible to make
>> it UDP and UDP only, and to put hooks in to have the traffic be handled by
>> a UDP protocol of the user's choosing.
> How would that help? Your problem seems to be to get SSH working at
> all. Since that doesn't work I guess it's difficult to use anything
> that exists *on top of* SSH?
> //Peter

Well, his problems are getting things to work on top of TCP, so he
proposes using
UDP instead.
It shouldn't be needed (TCP has automatic retransmissions and so on),
but I have
seen that behavior with ssh with a "lossy" network. If you were fast,
you could start
a session and get to the file list, but as soon as it started losing
packets, it froze.
Tweaking the TCP options with more aggressive resending should help.

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