Re: ssh & select() problem on 5.3

Hi,

Barney Wolff wrote:
> 
> Perhaps an MTU problem, with the ICMP "fragmentation needed but DF set"
> being blocked by the firewall?  It would only show up when the server
> has enough to send to fill a packet.
> 

I'm the friend he was talking about.

The very same thing happens when the firewall is disabled.

I tried from 5.2.1 console and same thing happens. However, we were
unable to reproduce the problem on any other servers. It only happens there.

No, it's not an ssh bug. I wrote a connect-back snippet and the same
thing happens when running commands with relatively big output (like dmesg).

I tried logging from 5.2.1 and 5.3 to different servers behind his
firewall, running also 5.3 and 5.2.1. The results are similar for all
the possible combinations.

A tcpdump shows that what actually happens is that packets won't reach
me in spite of the fact that his firewall(router)'s tcpdump shows that
he keeps sending them to me. Packets never reach me, but I am still able
to send them, by pressing ENTER on the ssh console.

Interesting fact is that I also get ACK packets for each of the packet I
send by pressing ENTER. However this is useless, as the connection is
already desynced and I receive no output. The connection times out in 5
minutes.

I hope I didn't use a way too obfuscated English.

PS: I personally suspect a hardware failure, probably an ethernet card,
and he is going to check this out tomorrow.

Regards,
-- 
Alin-Adrian Anton
Spintech Systems
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