Cisco Cisco ONS 15600 SDH, Руководство по устранению неисправностей

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Cisco ONS 15600 SDH Troubleshooting Guide, R8.0
July 2010
Chapter 1 General Troubleshooting
1.8.3 Free-Running Synchronization Mode
1.8.3 Free-Running Synchronization Mode
Symptom
The clock is running at a different frequency than normal and the FRNGSYNC alarm appears.
Free Running is reported when the node is running on the internal clock after a failure of the primary
and secondary clock references.
Table 1-20 describes the potential cause of the symptom and the solution.
1.8.4 Daisy-Chained BITS Not Functioning
Symptom You are unable to daisy-chain the BITS.
Table 1-21 describes the potential cause of the symptom and the solution.
1.8.5 Circuits Remain in PARTIAL Status
Symptom Circuits remain in the PARTIAL status.
Table 1-24 describes the potential cause of the symptom and the solution.
Table 1-20 Free-Running Synchronization Mode
Possible Problem Solution
No reliable reference
input is available. The clock is using the internal oscillator as its only frequency reference. This
occurs when no reliable, prior timing reference is available. See the
“FRNGSYNC” condition on page 2-64 for a detailed description.
Table 1-21 Daisy-Chained BITS Not Functioning
Possible Problem Solution
Daisy-chaining BITS is
not supported on the
ONS 15600 SDH. Daisy-chaining BITS causes additional wander buildup in the network and
is therefore not supported. Instead, use a timing signal generator to create
multiple copies of the BITS clock and separately link them to each
ONS 15600 SDH.
You cannot use BITS Out A and/or BITS Out B outputs when providing a
clock source from BITS In A and/or BITS In B inputs. To provide BITS
Out A and/or BITS Out B external outputs, the clock source must be derived
from an optical input.
Table 1-22 Circuits Remain in PARTIAL Status
Possible Problem Solution
The MAC address
changed. Repair the circuits. See the “Repair Circuits” procedure on page 1-69 .
The node is resetting. Wait for the node to finish the reset.