I can successfully register one IP phone on a SP trunk however, I cannot register anything more other than a softphone on the same trunk with the same auth credentials.
Any troubleshooting advice? All IP phones are Grandstream GXP2130, connected to the same switch, with identical configurations.
Try configuring them with different port numbers. Typically the default is 5060. Some ITSPs allow only one registration but your success with the softphone suggests that is not the issue in this case.
Otherwise, ask on a forum that supports your phones as your question does not appear to involve Obihai equipment or services.
I would move forward with an Asterisk setup but I'm stumped as to how I can get multiple PhonerLite instances to register with the same SP yet only one ip phone.
Is there any configuration I may be overlooking?
Will the 2nd phone register when the 1st is powered off?
Can the GXP2130 call without registration? It's the same setup with or without registration. I don't see the option in the user guide, but I know some phones will call after registration fails. I don't know if the GXP2130 is one of them.
Once I disabled SIP registration and support SIP instance ID, inbound/outbound started working correctly on all ip phones!
Now I just need to figure out if I can get SUBSCRIBE/NOTIFY messages to proxy through the service provider so that the BLF keys show idle/ringing/busy for the phones. That would practically eliminate the need to setup/maintain a software PBX at home.