Hi,

sip_provider_proxy1[ uac module-register] ---> kamailio [dispatcher Module]  ----> Asterisk1
                                                                                                                               ----> Asterisk 2

in my configuration kamailio register to the sip provider using uac module, sip information are stored in database (uacreg).

when a incoming call(INVITE) come to kamailio it will dispatch call to Asterisk using "dispatcher module".

Here i have couple of questions 

1.  If my SIP provider has a secondary proxy as a failover server (sip_provider_proxy2), can I configure Kamailio with the uac module to use the secondary proxy if the primary proxy fails?
2. Since my application is inbound-only, registration failure is only identified when the registration expires (3600 seconds = 1 hour). Can I use the dispatcher module to select the SIP proxy and switch the registration to the secondary proxy if the primary proxy is not reachable (using OPTIONS)?