[Pdns-users] NS caching bug reappears in recursor 3.1.6

[Kenneth Marshall]

Hello,

I would just like to add a report of my own regarding a caching
problem with version 3.1.6. I am not sure of the exact details,
but the scenario involves our main PDNS server serving rice.edu
and a subdomain xxx.rice.edu. The default ttl of rice.edu was
3600 and it was 86400 for xxx.rice.edu. The observed problem
was that the A record for xxx.rice.edu was not resolvable as
the MX for xxx.rice.edu. Making the ttl's the same at 3600 helped,
but in the end to work around the problem, I had to use the
forward-zones file to point xxx.rice.edu back to the auth PDNS
server to eliminate the A record lookup failures. Of course,restarting
the recursor let everything work smoothly for a while. Let me know
if there is anything else I can do to help resolve this problem.

Regards,
Ken

On Fri, May 16, 2008 at 03:43:44PM -0600, Darren Gamble wrote:
> Good day,
> 
> During our lab test suite on 3.1.6, we discovered that an old bug has
> unfortunately reappeared.  It's not present in 3.1.4.  We didn't test
> 3.1.5.
> 
> The issue is that the cache always caches information it receives in the
> Authority Section.  This can cause a problem where it indefinitely
> consults a server that is no longer supposed to be authoritative for a
> zone, but is still configured as such.
> 
> Here's the original thread:
> http://mailman.powerdns.com/pipermail/pdns-users/2006-May/003422.html 
> 
> ... where Bert noted he had originally fixed it in commit 837.
> 
> This is definitely a blocking issue for us.
> 
> Please let us know if we can provide any more information or help.
> Thanks!
> 
> ============================
> Darren Gamble
> Systems Architect, Regional Services
> Shaw Cablesystems GP
> 630 - 3rd Avenue SW
> Calgary, Alberta, Canada
> T2P 4L4
> (403) 781-4948
>  
> 
> _______________________________________________
> Pdns-users mailing list
> Pdns-users at mailman.powerdns.com
> http://mailman.powerdns.com/mailman/listinfo/pdns-users
>