Established connection timing out

Darren Tucker dtucker at dtucker.net
Tue Feb 27 12:37:24 AEDT 2018


On 27 February 2018 at 12:17, Kip Warner <kip at thevertigo.com> wrote:
[...]
> I am having problems with already established connections to a remote
> server

What platforms are the client and server?

> timing out after a few minutes. I connect either over ssh or via
> rsync tunnelled over the former.
>
> On the client side eventually I just see a whole pile of messages like
> this, but no rsync traffic appears occurring:
>
>     debug1: client_input_channel_req: channel 0 rtype     keepalive at ope
> nssh.com     reply 1

This sounds like some firewall or network device is aggressively
timing out TCP connections.  I suggest looking at the output of
netstat at both ends when it starts sending the keepalive packets and
finding the line corresponding to the SSH connection.  If the "Send-Q"
columns are non-zero and keep increasing it indicates that TCP is not
getting acks for the packets it's sending.  If that's the case you
have a broken network or firewall of some kind.

-- 
Darren Tucker (dtucker at dtucker.net)
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.


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