tcp delays in jails

[William Taylor]

On Dec 1, 2009, at 3:07 AM, Ivan Voras wrote:

> William Taylor wrote:
>> I recently started having a problem with tcp connections in one of my jails.
>> Im running 4.9-stable
> 
> I guess it will not do any good to tell you to upgrade to 8.0? :)
> 
   Not at this time although I probably should eventually.  I still have a 3.5-STABLE box kicking around.
   I have always been a believer of if it isn't broken don't fix it.

>> both sendmail and perdition experience the same problem. I even tried stopping
>> everything on the box and the problem still persists.
> 
> Just to verify - the problem is on the side of the servers (TCP listeners)?
> 
   Seems to be. I could write a small tcp server and see if I can get it to exhibit the same behavior or not.

>> Connections to other jails on different ip's on the same box are fine.
>> There seems to be about a 5 second delay.
>> From this snippet of a ktrace I did you can see what looks to be a delay of about 5 seconds  after the CALL kevent
> 
> I'm not sure what you are tracing but this trace looks like something having to do with DNS.
> 
> Does DNS resolve properly on the box? Reverse DNS also? Some servers, ssh and probably sendmail also, do a reverse DNS lookup on the connecting client.
> Just the generic ones... try seeing if DNS and reverse DNS work first.
> 
> 

Yes DNS is resolving properly forward and reverse. I even tried changing DNS servers.