Intermittent connection failure

[Michael Härtl]

Hi Matt,

thanks for your answer and sorry that my response took so long


Matt McCutchen schrieb:
> On Thu, 2008-11-13 at 10:29 +0100, Michael Härtl wrote:
>>
>> It sometimes works, but every third or fourth rsync fails with this message:
>>
>> rsync: failed to connect to ip.of.client.A: Connection refused (111)
>> rsync error: error in socket IO (code 10) at clientserver.c(104) 
>> [sender=2.6.9]
> 
> You mean ip.of.rsync.server, right?

Yes, correct, typo...

> 
> Try manually running "nc -v ip.of.rsync.server 873" a few times and see
> if you get the same "Connection refused".  If so, that means the rsync
> client is not at fault.  On the server side, you could try setting up
> the daemon under inetd and see if you get the same result and whether
> inetd logs anything useful.  You could even try "nc -l 873" on the
> server to see if the problem is purely with the network.
> 
>> There's also nothing in the logs.
> 
> I guess that would suggest that the daemon isn't seeing the incoming connection at all.

I think i've nailed it down now to some nameserver problem on the rsync 
server. Is it correct that rsync tries to do some reverse lookup on 
every client connect? It seems to me that the rsync server's nameserver 
had some connection issues and rsyncd stalled when trying to do the lookup.

I've now included all client hosts into /etc/hosts on the server and the 
problem seems to be gone now.

Does that sound plausible?

Thanks again
Mike