Internal server errors when creating SIP trunks typically indicate an issue with the termination URI format(1).
Verify your termination URI format:
The termination URI should follow this structure: sip:remote.server.or.ip.number:5060(2). It should not include a phone number(2).
For example, if connecting to IP 160.251.184.117, use: sip:160.251.184.117:5060(3)
Transport protocol specification:
You can specify the transport method by appending it to the SIP server URL(3):
- For TCP:
sip:160.251.184.117:5060;transport=tcp(3) - For UDP:
sip:160.251.184.117:5060;transport=udp(3) - For TLS:
sip:160.251.184.117:5060;transport=tls(3)
Phone number format:
When importing the phone number, ensure it’s in E.164 format with the country code prefixed with a plus sign (+)(4). For example: +14157774444(4).
Common issues:
If your service provider requires SIP REGISTER, the standard elastic SIP trunking mechanism may not work directly(2). In such cases, you might need an intermediate SBC or cloud service to handle the registration(2).
If the error persists after verifying these settings, check with your telephony provider’s logs or contact them for additional troubleshooting(3).