Hello, there are many topologies you can deploy in such case. If you want full independence of the head-office when they get disconnected from internet (so they can call in between them), then a clone system can be installed there (whatever you have kamailio+asterisk+mysql). Maybe makes sense to replicate the subscriber records, but I typically don't replicate dynamic data (e.g., location records), but I do kind of peering approach: if target user is not found registered on local kamailio, I forward to the other kamailio server, which can send 404 if not found there as well. Cheers, Daniel On 16/02/16 12:18, Sébastien Brice wrote: hosted server in a way to manage calls dialogs in a real-time fashion. (and to manage many customers) register their hardphone on the remote Kamailio Ipbx, to free them of ours end-of-life PABX (alcatel-Lucent). master mysql db? a replicated asterisk instance?) ? Taking into consideration disaster recovery plan What could be my options to maintain internal call if my internet provider get down by exemple. -- Daniel-Constantin Mierla http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda Book: SIP Routing With Kamailio - http://www.asipto.com http://miconda.eu _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list sr-users(a)lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users