Maintained by: NLnet Labs

[Unbound-users] Unbound stop working without error-log

lst_hoe02 at kwsoft.de
Tue Nov 2 11:38:16 CET 2010


Zitat von "W.C.A. Wijngaards" <wouter at NLnetLabs.nl>:

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> Hi Andreas,
>
> On 11/02/2010 11:13 AM, lst_hoe02 at kwsoft.de wrote:
>> we have unound 1.4.6 operating as caching resolver asking a border Bind
>> 9.7 as forwarder. This has worked for some time but today we got trouble
>> to resolve more and more domains/hosts. A restart a unbound cleared the
>> problem for some time but it failed again after some minutes. There is
>> nothing in the normal log either for the border Bind 9.7 or for unbound.
>> I have captured one failing event (www.computeruniverse.net) on the wire
>> an with unbound loglevel 4. The border Bind does resolve fine and quick,
>> but unbound does not deliver the result further on. This has happened
>> for many different domains over night according to mailserver logs. Any
>> hints how to debug this problem?
>
> In the debug log, it seems like unbound receives the reply just fine,
> and should be trying to do a send() call to send a reply to the user.
>
> The tcpdump does not show any reply from unbound to a user.  Unbound
> must be trying to send, and the syscall seems to work, or it would log
> an error.  Is there some routing issue?  (try interface-automatic: yes?)
>
> Best regards,
>    Wouter

The request is orginating at localhost with "nameserver 127.0.0.1" as  
the only content in resolv.conf so routing should not be the problem.  
If have disabled "interface-automatic: yes" because the machine is  
multihomed and have bound unbound to the needed interfaces "by hand"  
with the "interface:" statement. I have also set "do-ip6: no" because  
the machine has ipv6 capabilities but no ipv6 connectivity until yet.

Regards

Andreas