Full list The following SIP answers of your provider will cause 3Cx to skip down to the next route:
400 Bad Request, 401 Unauthorized, 402 Payment Required, 403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable
407 Proxy Authentication Required
408 Request Timeout
409 Conflict
410 Gone
411 Length Required
413 Request Entity too large
414 Request URI too long
415 Unsupported Media Type
416 Unsupported URI Scheme
420 Bad Extension
421 Extension Required
423 Interval too brief
433 Anonymity Disallowed
480 Temp Unavailable
481 Call Transaction does not exist
482 Loop Detected
483 Too many hops
484 Address Incomplete
485 Ambiguous
487 Request Terminated
500 Server Internal Error
501 Not Implemented
502 Bad Gateway
503 Service Unavailable
504 Server Timeout
505 Version Not Supported
513 Message Too Large
603 Decline
604 Does not exist anywhere
606 Not Acceptable