Asterisk SIP Settings for Failover WAN IP?

So I want to utilize failover internet. But when internet carrier #2 takes over my wan ip no longer matches what is found in the Asterisk SIP Settings and calls are disconnected with no audio. Do I switch to DHCP in the Chan SIP tab and input the DDNS found in system admin? Thanks!

Pretty much, but replace DHCP with Dynamic IP. (DHCP Option doesn’t exist). Put in your dynamic host name with a low refresh time and you should be good. If you have external phones also connected to this PBX you will need to take them into consideration as well.

Thank you! Do you think under Asterisk SIP Settings in the General SIP tab for the external IP I should put my dynamic host name or just leave that as the typical WAN IP and have the dynamic host name placed under the Chan SIP Tab?

As I understand it, putting the name in the CHAN_SIP section overrides the General parameters. Leave the general as is, and put your dynamic host in the Chan_SIP section.