Here is a table of the IAX2 to assist with debugging IAX2 call issues
More IAX2 information can be found here and the RFC is here
CSV download is here
| Number | Cause | Reference |
|---|---|---|
| 1 | Unassigned/unallocated number | [RFC5457] |
| 2 | No route to specified transit network | [RFC5457] |
| 3 | No route to specified transit network | [RFC5457] |
| 4-5 | Unassigned | |
| 6 | Channel unacceptable | [RFC5457] |
| 7 | Call awarded and delivered | [RFC5457] |
| 8-15 | Unassigned | |
| 16 | Normal call clearing | [RFC5457] |
| 17 | User busy | [RFC5457] |
| 18 | No user response | [RFC5457] |
| 19 | No answer | [RFC5457] |
| 20 | Unassigned | |
| 21 | Call rejected | [RFC5457] |
| 22 | Number changed | [RFC5457] |
| 23-26 | Unassigned | |
| 27 | Destination out of order | [RFC5457] |
| 28 | Invalid number format/incomplete number | [RFC5457] |
| 29 | Facility rejected | [RFC5457] |
| 30 | Response to status enquiry | [RFC5457] |
| 31 | Normal, unspecified | [RFC5457] |
| 32-33 | Unassigned | |
| 34 | No circuit/channel available | [RFC5457] |
| 35-37 | Unassigned | |
| 38 | Network out of order | [RFC5457] |
| 39-40 | Unassigned | |
| 41 | Temporary failure | [RFC5457] |
| 42 | Switch congestion | [RFC5457] |
| 43 | Access information discarded | [RFC5457] |
| 44 | Requested channel not available | [RFC5457] |
| 45 | Pre-empted (causes.h only) | [RFC5457] |
| 46 | Unassigned | |
| 47 | Resource unavailable, unspecified (Q.931 only) | [RFC5457] |
| 48-49 | Unassigned | |
| 50 | Facility not subscribed (causes.h only) | [RFC5457] |
| 51 | Unassigned | |
| 52 | Outgoing call barred (causes.h only) | [RFC5457] |
| 53 | Unassigned | |
| 54 | Incoming call barred (causes.h only) | [RFC5457] |
| 55-56 | Unassigned | |
| 57 | Bearer capability not authorized | [RFC5457] |
| 58 | Bearer capability not available | [RFC5457] |
| 59-62 | Unassigned | |
| 63 | Service or option not available (Q.931 only) | [RFC5457] |
| 64 | Unassigned | |
| 65 | Bearer capability not implemented | [RFC5457] |
| 66 | Channel type not implemented | [RFC5457] |
| 67-68 | Unassigned | |
| 69 | Facility not implemented | [RFC5457] |
| 70 | Only restricted digital information bearer capability is available (Q.931 only) | [RFC5457] |
| 71-78 | Unassigned | |
| 79 | Service or option not available (Q.931 only) | [RFC5457] |
| 80 | Unassigned | |
| 81 | Invalid call reference | [RFC5457] |
| 82 | Identified channel does not exist (Q.931 only) | [RFC5457] |
| 83 | A suspended call exists, but this call identity does not (Q.931 only) | [RFC5457] |
| 84 | Call identity in use (Q.931 only) | [RFC5457] |
| 85 | No call suspended (Q.931 only) | [RFC5457] |
| 86 | Call has been cleared (Q.931 only) | [RFC5457] |
| 87 | Unassigned | |
| 88 | Incompatible destination | [RFC5457] |
| 89-90 | Unassigned | |
| 91 | Invalid transit network selection (Q.931 only) | [RFC5457] |
| 92-94 | Unassigned | |
| 95 | Invalid message, unspecified | [RFC5457] |
| 96 | Mandatory information element missing (Q.931 only) | [RFC5457] |
| 97 | Message type nonexistent/not implemented | [RFC5457] |
| 98 | Message not compatible with call state | [RFC5457] |
| 99 | Information element nonexistent | [RFC5457] |
| 100 | Invalid information element contents | [RFC5457] |
| 101 | Message not compatible with call state | [RFC5457] |
| 102 | Recovery on timer expiration | [RFC5457] |
| 103 | Mandatory information element length error (causes.h only) | [RFC5457] |
| 104-110 | Unassigned | |
| 111 | Protocol error, unspecified | [RFC5457] |
| 112-126 | Unassigned | |
| 127 | Internetworking, unspecified | [RFC5457] |
| 128-255 | Unassigned |