SIP 181 Call Is Being Forwarded vs 500 Server Internal Error
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 500 (Server Internal Error) is a 5xx Server Failure response. 181 indicates that a proxy server may send this to indicate that the call is being forwarded to a different set of destinations. In contrast, 500 means that the server encountered an unexpected condition that prevented it from fulfilling the request.
Descripción
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
Cuándo lo verás
When the callee has call forwarding enabled and the request is being redirected to another number or device.
Cómo solucionarlo
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
Descripción
The server encountered an unexpected condition that prevented it from fulfilling the request.
Cuándo lo verás
When the SIP server has an internal error — database failure, unhandled exception, or resource exhaustion.
Cómo solucionarlo
Check server logs for the specific error. Common causes include database connectivity issues, configuration errors, or memory exhaustion.
Diferencias clave
181 is a 1xx Provisional response, while 500 is a 5xx Server Failure response.
SIP 181: A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
SIP 500: The server encountered an unexpected condition that prevented it from fulfilling the request.
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 500 when when the SIP server has an internal error — database failure, unhandled exception, or resource exhaustion.
Cuándo usar cada uno
For 181 (Call Is Being Forwarded): No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings. For 500 (Server Internal Error): Check server logs for the specific error. Common causes include database connectivity issues, configuration errors, or memory exhaustion.