Hi experts,

We have a POS port going to our upstream provider. Recently we've noticed lots of errors on the port. We've tried changing the sfp and line cards to no avail. We have contacted our upstream provider, but they found nothing on there end...

Could it be a clocking issue?

See below logs:

Mar 22 12:58:31 SCT: %SONET-4-ALARM:  POS3/0/1: PAIS declared

Mar 22 12:58:32 SCT: %SONET-4-ALARM:  POS3/0/1: B3 declared

Mar 22 12:58:41 SCT: %LINEPROTO-5-UPDOWN: Line protocol on Interface POS3/0/1, changed state to down

Mar 22 12:58:42 SCT: %SONET-4-ALARM:  POS3/0/1: B3 cleared

Mar 22 12:58:43 SCT: %SONET-4-ALARM:  POS3/0/1: PAIS cleared

Mar 22 12:59:03 SCT: %LINEPROTO-5-UPDOWN: Line protocol on Interface POS3/0/1, changed state to up

Mar 22 13:03:32 SCT: %SONET-4-ALARM:  POS3/0/1: PRDI declared

Mar 22 13:03:43 SCT: %SONET-4-ALARM:  POS3/0/1: PRDI cleared

Mar 22 18:07:03 SCT: %SONET-4-ALARM:  POS3/0/1: PRDI declared

Mar 22 18:07:03 SCT: %SONET-4-ALARM:  POS3/0/1: B3 declared

Mar 22 18:07:04 SCT: %SONET-4-ALARM:  POS3/0/1: PAIS declared

Mar 22 18:07:13 SCT: %SONET-4-ALARM:  POS3/0/1: B3 cleared

Mar 22 18:07:15 SCT: %SONET-4-ALARM:  POS3/0/1: PAIS cleared

Mar 22 18:07:16 SCT: %SONET-4-ALARM:  POS3/0/1: PRDI cleared

Mar 22 18:07:24 SCT: %LINEPROTO-5-UPDOWN: Line protocol on Interface POS3/0/1, changed state to down

Mar 22 18:07:45 SCT: %LINEPROTO-5-UPDOWN: Line protocol on Interface POS3/0/1, changed state to up

Mar 23 14:36:36 SCT: %SONET-4-ALARM:  POS3/0/1: PAIS declared

Mar 23 14:37:06 SCT: %SONET-4-ALARM:  POS3/0/1: B3 declared

Mar 23 14:37:07 SCT: %LINEPROTO-5-UPDOWN: Line protocol on Interface POS3/0/1, changed state to down

Mar 23 14:37:16 SCT: %SONET-4-ALARM:  POS3/0/1: B3 cleared

Mar 23 14:37:17 SCT: %SONET-4-ALARM:  POS3/0/1: PAIS cleared

Mar 23 14:37:28 SCT: %LINEPROTO-5-UPDOWN: Line protocol on Interface POS3/0/1, changed state to up

Thanks to advise.

Regards Steve