Had bit of a gotcha moment which caught me out and took a little longer than I would have liked to resolve.
The customer was experiencing the whole port network reset but from the logs we were seeing sanity errors, they investigated the network and found nothing. I replaced the IPSI board, cable and adapter but no change and we reached a stalemate both thinking it was each other. In the event we run a wireshark trace on the port but that came to nothing.
By accident while searching the Avaya site for IPSI related issues I came across an old Avaya PSN1380u issued back in 2007. In affect a momentary power shutdown can be caused when CM performs Test 51 Ring Application Test on TN2215 boards.
The resolution is to either install an additional TN2215 in the rack, replace it with a TN2215 vintage 18 or higher or replace the power supplies with units without the DT in the serial number. In this case the analogue TN2215 card which was at vintage 15, along with the 655A power supply’s having DT serial numbers.
I busied out the analogue board and disabled test 51 as a temporary measure and it stopped.
01A08 ANALOG LINE TN2215 000015
01A00 08DT50664809 Power Unit 655A Rev 01 700381452 1.12
01A15 08DT37555245 Power Unit 655A Rev 01 700381452 1.12