[Users] redundancy

[Steve Blair]

Ramin Dousti wrote:

> Hi Antoine,
>
> Unfortunately the site is unavailable (I'll keep trying).
>
> On the same token, I need to have some kind of redundancy. Someone
> on the list recommended the usage of NAPTR, SRV for that matter but
> as Bogdan pointed out that mechanism does not support automatic failover
> in its current state.
>
> Let me re-iterate my question, is there any way I could implement the
> failover mechanism based on the DNS A records within the configuration
> file. I've been going through the documentations and been unable to spot
> such a setting. Does anyone have any configuration snippet that shows how
> to "try this destination first, if the destination is unreachable, 
> then try that
> destination". Please note that the failover I'm looking for is only 
> with regards
> to the IP-connectivity failure, meaning if the next hop is not there I 
> want to
> failover, and not if the transaction to the next hop fails with some 
> legitimate
> return code.


In the proxy you can check the status of the t_relay and take corrective 
action based on the result. Something like "if (t_check_status("403")) 
... do something... " should work. What action you take will depend upon 
the desired outcome. You could send the call to voicemail, a greeting 
server, a different gateway, etc.

In the phones you can use SRV records to present a weighted list of 
proxy servers. The phone would register to a domain name which is a SRV 
record. This record resolves into the A records for each viable proxy. 
You could weight and prioritize the A records thereby giving the phones 
an ordered list of servers to try.

-Steve

>
> Thanks everyone for your time/help.
>
> Ramin
>
> On 9/20/06, Antoine Fressancourt <af.devlist at gmail.com> wrote:
>
>> I don't really know if it can help, but Jan Janak made a presentation
>> at the last FOSDEM about such redundancy problematics. It is
>> available at : http://www.iptel.org/jan/
>>
>> I hope it helps a bit...
>>
>> Antoine
>>
>> Le 19 sept. 06 à 20:38, Ramin Dousti a écrit :
>>
>> > Hi,
>> >
>> > A SIP INVITE to sip.mydoamin.com with sip.mydomain.com having two A-
>> > RR's, must
>> > be forwarded to the first IP and if that IP is unreachable then to the
>> > second IP. How can
>> > I achieve this?
>> >
>> > My first problem is that I seem to not have the list of the two IP's
>> > available to me via a
>> > configuration key-word. So I need to hardcode the IP's in my conf
>> > file.
>> >
>> > My second problem is I don't know how to iterate over these two IP's.
>> > Maybe I can
>> > use t_on_failure() and have the second IP processed in the
>> > failure_route[]. But then
>> > again, how can I distinguish between a timeout and a legitimate
>> > failure?
>> >
>> > Thank you in advance,
>> >
>> > --
>> > Ramin
>> >
>> > _______________________________________________
>> > Users mailing list
>> > Users at openser.org
>> > http://openser.org/cgi-bin/mailman/listinfo/users
>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at openser.org
>> http://openser.org/cgi-bin/mailman/listinfo/users
>>
>
>

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