[Pdns-users] Possible tcp listener issue

[Simon Bedford]

Please see answers below, thanks.

bert hubert wrote:
> On Tue, May 04, 2010 at 05:04:51PM +0100, Simon Bedford wrote:
> 
>>> We created a patched version in the end and rolled to one server
>>> back on the 8th April, no fault seen since and now rolled to the
>>> entire platform as of today, looking good.
>> We have now had 2 more failures of the tcp listener on 2 seperate
>> servers in the last week, a simple reload of the software fixes
> 
> So this is with the patched servers?

Yes

> 
>> this. the thing I have noticed when this occurs is that when
>> telnetting to the port you can then type in anything and try and
>> escape, etc but the connection never closes, whereas on a working
>> server the session will close after a short while of typing and
>> pressing Enter.
>>
>> The logs do not show anything or give any pointers as to the cause...
> 
> Please remind us of your operating system, RHEL4 I think? Or 5? Is there
> anything special about your workload? Residential internet connections I
> think? 
>

Debian Etchnhalf and Lenny.

Just run of the mill DSL connection DNS requests.

> How many TCP/IP queries do you see per second, roughly? A quick run of
> rec_control should dig this up.

date;rec_control get tcp-questions
Tue May  4 17:34:22 BST 2010
79371

date;rec_control get tcp-questions
Tue May  4 17:35:53 BST 2010
79924

Gives us rough stats from a short period of 6 tcp requests per second 
per server, theres 8 servers.

> 
> 	Bert

Simon