said by DSLR98004:I have multiple three-line Aastra SIP phones (9143i). I actually only use lines 1 and 2 on a normal basis (one home office line and one personal residence line). Those two lines (DIDs) are registered to the Seattle server. I have a third line/DID that is registered to Houston but is normally not used ($0.99/month insurance).
On my Aastra 6730i I have options to specify backup that seems to work automatically. For line 1 I set:
Proxy Server=tampa.voip.ms
Backup Proxy Server=chicago.voip.ms
Registrar Server=tampa.voip.ms
Backup Registrar Server=chicago.voip.ms
The Status screen field Backup Registrar Used? reports YES or NO to let you know which server is in use.
I will be looking for something other than an Obi with similar functions for the main house unless someone can tell me how to do something like this on an Obi.