SIP 300 Multiple Choices vs 500 Server Internal Error
SIP 300 (Multiple Choices) is a 3xx Redirection response, while 500 (Server Internal Error) is a 5xx Server Failure response. 300 indicates that the address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint. In contrast, 500 means that the server encountered an unexpected condition that prevented it from fulfilling the request.
Description
The address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
When You See It
When a user has multiple registered devices or contact addresses and the server cannot determine which one to use.
How to Fix
Select one of the provided Contact addresses and resend the request to that specific URI.
Description
The server encountered an unexpected condition that prevented it from fulfilling the request.
When You See It
When the SIP server has an internal error — database failure, unhandled exception, or resource exhaustion.
How to Fix
Check server logs for the specific error. Common causes include database connectivity issues, configuration errors, or memory exhaustion.
Key Differences
300 is a 3xx Redirection response, while 500 is a 5xx Server Failure response.
SIP 300: The address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
SIP 500: The server encountered an unexpected condition that prevented it from fulfilling the request.
You encounter 300 when when a user has multiple registered devices or contact addresses and the server cannot determine which one to use.
You encounter 500 when when the SIP server has an internal error — database failure, unhandled exception, or resource exhaustion.
When to Use Which
For 300 (Multiple Choices): Select one of the provided Contact addresses and resend the request to that specific URI. For 500 (Server Internal Error): Check server logs for the specific error. Common causes include database connectivity issues, configuration errors, or memory exhaustion.