[SR-Users] Avoid resolving names by DNS

[Santiago Soares]

Hello,

Both options (dns_cache_init=no and use_dns_cache=no) worked for me.
I think that the internal resolver is used only if cache is enabled.
Thank you!

Santiago Soares
Fone: (41) 8488-0537


On Wed, Sep 1, 2010 at 2:09 PM, Daniel-Constantin Mierla
<miconda at gmail.com>wrote:

>
>
> On 9/1/10 7:01 PM, Andrei Pelinescu-Onciul wrote:
>
>> On Sep 01, 2010 at 18:49, Klaus Darilion<klaus.mailinglists at pernau.at>
>>  wrote:
>>
>>> kamailio>= 3.0 is based on ser's core which has implemented its own
>>> caching resolver library. I do not know if there is a way to disable
>>> it complete and use the system's stub resolver. You could try the
>>> "use_dns_cache" option:
>>> http://sip-router.org/wiki/cookbooks/core-cookbook/devel#dns_parameters
>>>
>> Yes, if you disable the dns cache it will use the system resolver.
>>
>
> when the cache is enabled and the record is not cached, will first dns
> query find the records in /etc/hosts and then cache it? Or in other words,
> if a query to internal cache fails, then is used the system resolver?
>
> Just for sake of completing info in this thread, disabling completely the
> internal cache is by global parameter:
> dns_cache_init=no
>
> Thanks,
> Daniel
>
>
>  It's also used during the initial startup phase, when the dns cache is
>> not yet fully initialized.
>>
>> You could also leave the cache enabled and add/remove records by hand
>> (using sercmd or xmlrpc) using the dns rpcs (e.g. dns_add_a,
>> dns.add_srv, dns.delete_a a.s.o, for more info see
>>
>> http://sip-router.org/docbook/sip-router/branch/master/rpc_list/rpc_list.html#dns.add_a
>> ).
>>
>> Andrei
>>
>>  regards
>>> klaus
>>>
>>> Am 01.09.2010 17:10, schrieb Santiago Soares:
>>>
>>>> Hello,
>>>>
>>>> I'm using kamailio as a simple load balancer.
>>>> My dispatcher list is something like that:
>>>>
>>>> 1   sip:server1:5060
>>>> 1   sip:server2:5060
>>>> 2   sip:server1:5060
>>>>
>>>> and /etc/hosts is
>>>>
>>>> 10.1.1.1   server1
>>>> 10.1.1.2   server2
>>>>
>>>> When I want to do some maintenance task in one of the servers, server2,
>>>> for exemple, I simply change /etc/hosts like that:
>>>>
>>>> 10.1.1.1   server1
>>>> 10.1.1.1   server2
>>>>
>>>> And all the traffic is redirected to server 1. It's a simple yet
>>>> effective way to remove a server from balancing.
>>>> The thing is that it works on kamailio 1.5.3, but on kamailio 3.0.3 it
>>>> doesn't work, since kamailio appears to resolv names only by DNS.
>>>> I receive this message on startup:
>>>>
>>>> Sep  1 12:04:32 install /usr/local/sbin/kamailio[16077]: ERROR:
>>>> dispatcher [dispatch.c:241]: could not resolve server1
>>>> Sep  1 12:04:32 install /usr/local/sbin/kamailio[16077]: ERROR:
>>>> dispatcher [dispatcher.c:247]: no dispatching list loaded from file
>>>> Sep  1 12:04:32 install /usr/local/sbin/kamailio[16077]: ERROR:<core>
>>>> [sr_module.c:874]: init_mod(): Error while initializing module
>>>> dispatcher
>>>>
>>>>
>>>> Is there any way to avoid this behavior, and force kamailio to use
>>>> /etc/hosts?
>>>>
>>>> Thank you.
>>>>
>>>> Santiago Soares
>>>> Fone: (41) 8488-0537
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
>>>> sr-users at lists.sip-router.org
>>>> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>>>>
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>> _______________________________________________
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>>
>>
> --
> Daniel-Constantin Mierla
> http://www.asipto.com/
>
>
> _______________________________________________
> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
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