Enhanced disaster recovery solution for outbound calls
Introduced in SIP Server version 8.1.103.78. After receiving a negative response, SIP Server can now select an alternative trunk for outbound calls. In addition, SIP Server can now attempt to connect to a DN via an alternative softswitch (found in the DN configuration) if the first attempt to connect to a DN via a softswitch resulted in a negative response from that softswitch.
The following Application-level option supports this feature:
sip-error-codes-overflow
Setting: [TServer] section, SIP Server Application
Default Value: An empty string (or 503 error code)
Valid Values: A list of patterns for numeric error codes separated by a comma (,). Letter X in a pattern represents any digit. A single pattern must start with a digit and contain all 3 digits, and a pattern containing "X" should conclude the pattern's list, if present.
Examples:
- 503
- 503,504
- 487,50X
- 487,5XX
- Patterns 5X3,XXX are invalid
Changes Take Effect: For the next call
When, on an initial INVITE message, SIP Server receives a negative response containing the error code that matches the option value setting, SIP Server attempts to find an alternative trunk or softswitch to initiate a call.