Avaya 03-300430 User Manual

The EPN Sanity Audit feature enhances the system’s ability to recover from failure conditions 
that disable an entire PN. In such situations, not only is the affected PN unable to provide 
service to the system, but the system itself has not detected the condition. The EPN Sanity 
Audit feature recognizes a PN as unable to provide service when the software cannot receive 
control messages from PN circuit packs. When such a failure is detected by the EPN Sanity 
Audit, a sequence of recovery actions is triggered to restore the PN to service.

For a standard-reliability system (unduplicated server), the recovery sequence is:

1. TDM bus switch

2. EPN WARM reset

3. EPN COLD reset

The recovery sequence is:

1. TDM bus switch

2. Tone-Clock switch within the PN

3. PNC interchange

4. PN WARM reset

5. PN COLD reset

The EPN Sanity Audit feature activates only when every existing maintenance operation has 
failed to detect the PN problem. The EPN Sanity Audit serves as a safety net for the PN.

Note:

It is not clear why certain types of PN problems activate this feature. Thus, error 
log entries related to these problems do not specify which hardware to replace. 
The error log entries only indicate that some drastic recovery action occurred due 
to an unknown problem. However, clues as to the root cause of the PN outage 
may be present in the Error Logs and the Alarm Logs of the following MOs: 

on page 1176, and 

on page 1235, and 

page 1851. You should refer to these maintenance sections during 
troubleshooting operations.

EPN-SNTY

None

None

EPN Sanity Audit