Locate Loss of Pointer Path Alarms
Purpose
A loss of pointer path (LOP-P) alarm indicates a possible provisioning problem and occurs when the Juniper Networks router cannot determine a valid payload pointer. The Juniper Networks router monitors the H1/H2 bytes, located in the line overhead area. This alarm is usually discovered upon initial provisioning of SONET circuits, and is not generally seen after the router has been deployed in the network for some time.
Action
To display SONET alarms and errors, use the following JUNOS CLI operational mode command:
user@host>show interfacesso-fpc/pic/portextensive
Sample Output
user@host> show interfaces so-1/1/1 extensive
[...Output truncated...]
SONET alarms : LOP
SONET defects : LOP
SONET PHY: Seconds Count State
PLL Lock 0 0 OK
PHY Light 0 0 OK
SONET section:
BIP-B1 0 0
SEF 0 0 OK
LOS 0 0 OK
LOF 0 0 OK
ES-S 0
SES-S 0
SEFS-S 0
SONET line:
BIP-B2 0 0
REI-L 0 0
RDI-L 0 0 OK
AIS-L 0 0 OK
BERR-SF 0 0 OK
BERR-SD 0 0 OK
ES-L 0
SES-L 0
UAS-L 0
ES-LFE 0
SES-LFE 0
UAS-LFE 0
SONET path:
BIP-B3 0 0
REI-P 0 0
LOP-P 174 0 Defect Active
AIS-P 0 0 OK
RDI-P 0 0 OK
UNEQ-P 0 0 OK
PLM-P 0 0 OK
ES-P 174
SES-P 174
UAS-P 174
ES-PFE 0
SES-PFE 0
UAS-PFE 0
[...Output truncated...]
What It Means
The sample output shows that an LOP-P alarm occurred for 174 seconds. An LOP-P alarm can occur when the ADM on the other end is configured for nonconcatenate mode, while the Juniper Networks router is configured for concatenate mode (the default setting). In this instance, the pointer word in the required STS frame does not have the concatenation indicator set.
The condition of 8, 9, or 10 consecutive frames without valid pointer values can raise an LOP-P alarm.
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NOTE: Although Juniper routers do not report pointer adjustments, an LOP-P alarm will not occur as long as the pointer adjustments stay within tolerance levels. |