Cisco ONS 15310-CL, Руководство по устранению неисправностей

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Cisco ONS 15310-CL and Cisco ONS 15310-MA Troubleshooting Guide, R7.0
78-17235-01
Chapter 1 General Troubleshooting
1.10.5 OC-3 and DCC Limitations
1.10.5 OC-3 and DCC Limitations
Symptom There are limitations to OC-3 and DCC usage.
Table 1-24 describes the potential cause of the symptom and the solution.
1.10.6 ONS 15310-CL or ONS 15310-MA Switches Timing Reference
Symptom
Timing references switch when one or more problems occur.
Table 1-25 describes the potential causes of the symptom and the solutions.
Table 1-23 Circuit Creation Error with VT1.5 Circuit
Possible Problem Solution
You might have run out
of bandwidth on the VT
cross-connect matrix at
the node indicated in the
error message. The ONS 15310-CL matrix has a maximum capacity of 336 bidirectional
VT1.5 cross-connects. The ONS 15310-MA capacity is 1,064.
Table 1-24 OC-3 and DCC Limitations
Possible Problem Solution
OC-3 and DCC have
limitations for the
system. For an explanation of OC-3 and DCC limitations, refer to the “DCC
Tunnels” section in the
Cisco ONS 15310-CL and Cisco ONS 15310-MA
Procedure Guide .
Table 1-25 ONS 15310-CL or ONS 15310-MA Switches Timing Reference
Possible Problem Solution
The optical or building integrated timing supply
(BITS) input is receiving loss of signal (LOS), loss of
frame (LOF), or AIS alarms from its timing source. The node internal clock operates at a
Stratum 3 level of accuracy. This gives the
node a free-running synchronization accuracy
of +/–4.6 ppm and a holdover stability of less
than 255 slips in the first 24 hours or 3.7 x
10
–7
per day, including temperature.
Node free-running synchronization relies on
the Stratum 3 internal clock.
Use a higher quality Stratum 1 or Stratum 2
timing source. This results in fewer timing
slips than a lower quality Stratum 3 timing
source.
The optical or BITS input is not functioning.
Synchronization status message (SSM) is set to Don’t
Use for Synchronization (DUS).
SSM indicates a Stratum 3 or lower clock quality.
The input frequency is off by more than 15 ppm.
The input clock wanders and has more than three slips
in 30 seconds.
A bad timing reference existed for at least two
minutes.