Hi Mahmoud,

Thy typical way, to build a Active/Active setup is by using DNS-SRV
records. The two servers get different IPs and you announce both IPs
using DNS to the devices. Most common User-Agents support this
nowadays, so that's kind of easy. It is specified in RFC3263:
"Locating SIP-Servers" (http://tools.ietf.org/html/rfc3263).

However, when using DNS-SRV records, dialogs and transactions are
still associated with a single server, even though the User-Agent has
an Alternative, in case one server fails. If you want to increase the
HA for this, you can advertise the Domain name instead of an IP
(causes more DNS-Lookups).

You can share the dialog state between two nodes by using the dialog
module in db-only mode (db_mode = 1, see
http://kamailio.org/docs/modules/devel/modules/dialog.html#idp15368320).
You cannot share transactions between two nodes, only dialogs.

In addition, you can work with virtual IPs with Heartbeat/Pacemaker.

At a big operator, we've used a combination of the two: Active/Passive
for one site and DNS-SRV to distribute it among different sites.

Kind regards,
Carsten

2014-12-26 19:07 GMT+01:00 Mahmoud Ramadan Ali <cisco.and.more.blog@gmail.com>:
> Hi Dears,
> I have successfully configured Kamailio HA using Heartbeat and Pacemaker so
> if one of the two servers should go down the other server will own the
> virtual IP address and take over.
> But i have two questions:
>
> 1.This model is considered to be Active / Passive redundancy so one server
> will process the SIP signaling until it goes down and i'm wondering is there
> is any way two achieve Active / Active redundancy and if so how the
> signaling will be handled on the servers so they can be aware of the
> transactions and dialogs traversing the servers ? does the signalling will
> be replicated or synchronized between the servers or what ?!
>
> 2.What about the servers DB and how they should be designed in a cluster
> mode ? i want to replicate all the DBs of the server to get consistent user
> registration using the subscriber table for example.
>
> Thanks in advance and Best regards.
>

> _______________________________________________
> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
> sr-users@lists.sip-router.org
> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>



--
Carsten Bock
CEO (Geschäftsführer)

ng-voice GmbH
Schomburgstr. 80
D-22767 Hamburg / Germany

http://www.ng-voice.com
mailto:carsten@ng-voice.com

Office +49 40 5247593-0
Fax +49 40 5247593-99

Sitz der Gesellschaft: Hamburg
Registergericht: Amtsgericht Hamburg, HRB 120189
Geschäftsführer: Carsten Bock
Ust-ID: DE279344284

Hier finden Sie unsere handelsrechtlichen Pflichtangaben:
http://www.ng-voice.com/imprint/

_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users@lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users