We have an ATM network with 8540 and 8510 ATM switches. We have designed NCDP in such a way that that the priority 1,2,3,4 clock sources are the PABX. Priority 5 clock source is the internal system clock. Every few day we believe that there is a PABX issue whereby the clock fails over to the priority 5 internal system clock which is fair enough. But when the PABX clock becomes stable again the 85xx switches don't revert back to the PABX clock and stay using the internal system clock, although we have configured to revert. As a temporary work-around we have to remove and re-apply the ncdp commands for the 85xx to start using the PABX clock again.
