[Users] Dns resolution failure..

Kir Kolyshkin kir at openvz.org
Wed Jun 14 08:26:07 EDT 2006


I suggest to turn on the dump mode and check that /etc/resolv.conf in a 
VE contains the same as on the hardware node. If not, use vzctl set VEID 
--nameserver x.x.x.x --save command.

Next step is to try pinging the nameserver from inside a VE.

Kirill Korotaev wrote:

> Hello Aaron,
>
>> We've gone down that route with no results.
>>
>> What's bugging me (and I can't wrap my brain around it) is that we 
>> can ping the outside world, wget to IP addresses, and ssh into 
>> external hosts.
>
> from VPS, correct?
>
> > The only thing that seems to be failing is DNS at the
>
>> application level.. Again, nslookup and host both work without issue.
>
> does dig <some domain> works correctly?
> does ping <some domain> works?
>
> do tcpdump (both in VPS and host) and check why UDP packets from 
> applications DNS request fail.
>
> Also check that you have no any firewalls in host/VPS.
>
> I feel that there is something simple, but can't say what is wrong 
> yet...  :)
>
> Thanks,
> Kirill
>
>> -=Aaron
>>
>> Kirill Korotaev wrote:
>>
>>> You need to check with tcpdump in the host whether your packets go 
>>> ok from VE to host system.
>>> Does networking work correctly from VE when IP addresses are used?
>>>
>>> Kirill
>>>
>>>> Hey all,
>>>>
>>>> We're seeing a problem where within one particular VE on a host we 
>>>> can nslookup or "host" a hostname and everything works.
>>>>
>>>> But when we try running yum update or wget (even to 
>>>> www.google.com)  we get "Temporary failure in  name resolution."
>>>>
>>>> We've dug around on the lists and tried solutions posted there with 
>>>> no luck (w.r.t setting forwarding on the main system, etc).
>>>>
>>>> We're also seeing the following in the logs (not sure if it's a 
>>>> red-herring or not):
>>>>
>>>> Jun 12 15:48:19 FOO sysctl: net.ipv4.ip_forward = 0
>>>> Jun 12 15:48:19 FOO sysctl: error: unknown error 1 setting key 
>>>> 'net.ipv4.conf.default.rp_filter'
>>>> Jun 12 15:48:19 FOO sysctl: error: unknown error 1 setting key 
>>>> 'net.ipv4.conf.default.accept_source_route'
>>>> Jun 12 15:48:19 FOO sysctl: error: unknown error 1 setting key 
>>>> 'kernel.sysrq'
>>>> Jun 12 15:48:19 FOO sysctl: error: unknown error 1 setting key 
>>>> 'kernel.core_uses_pid'
>>>>
>>>>
>>>> I should mention that all other VE's running on the host work 
>>>> without a problem.
>>>>
>>>> Any ideas?
>>>>
>>>> _______________________________________________
>>>> Users mailing list
>>>> Users at openvz.org
>>>> https://openvz.org/mailman/listinfo/users
>>>
>>>
>>>
>>> _______________________________________________
>>> Users mailing list
>>> Users at openvz.org
>>> https://openvz.org/mailman/listinfo/users
>>
>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at openvz.org
>> https://openvz.org/mailman/listinfo/users
>
>
> _______________________________________________
> Users mailing list
> Users at openvz.org
> https://openvz.org/mailman/listinfo/users
>


More information about the Users mailing list