Customer asked about LTI alarms were observed on many NEs in Ring when clock was re-configured after adding new external clock source in that Ring. NE version is V1R1. Software version is 188.8.131.52P02.
LTI on 9&10-EXCSA-OTHERS
Parameters: 0X03 0X00 0X01 0Xff 0Xff
According to alarm parameters, this was due to setting wrong "Priority Table For Phase-Locked Sources of 1st/2nd External Clock Output". In order to avoid LTI alarms, configure clock according to the attached diagram.
According to attached diagram there are possiblities shown for LTI alarm. Other possiblilities are as below:
1) After setting wrong "Priority Table For Phase-Locked Sources of 2nd External Clock Output" LTI alarm appeared on both cross connect boards.
2) NE went isolated from other NEs in a ring therefore LTI alarm appears.
For case of NE B: LTI appeared when you will add 8-SL64 in “Priority Table For Phase-Locked Sources of 1st/2nd External Clock Output”. This is because NE C is not directly receiving working clock from west side. By avoiding this we can get rid of LTI alarms.