How can I switch the SIP adapter to a standby Asterisk?

Question

Asterisk

There are primary and backup Asterisk servers (located in different geographical locations). The VoIP adapters are configured to connect to the primary server. Sometimes this primary server becomes unavailable and it is necessary to switch to a backup. In order to do this, you need to register a different IP address through the web interface.
Is there another way to solve this issue? For example, through DHCP Option or POST request, or some other option. Cisco SPA-122 and their younger brothers - LinkSys SPA2102 act as adapters. Perhaps there is a completely different approach to organizing the main and backup servers.

Answer 1

The best option is through DNS - dynamically change the pointer to the working server in DNS.
Some equipment can work with 2 servers - if responses to REGISTRY or INVITE packets are lost, it dynamically switches to a spare

Answer 2

I will offer a solution "on the forehead". Connect all adapters via sip-proxy (for example, siproxd) and switch servers on it. This is already one place, not many web interfaces.
Further, if desired, a script in cron, which every minute checks the availability of servers and, in case of a crash, changes the ip of the server in siproxd and re-reads its config.