Troubleshooting guide

Troubleshooting the CMTS
4-47
High P-Adj (power adjustment) This condition can indicate that the fiber
node is clipping the upstream return laser.
Evaluate the CMs with the highest number
of correcteds and uncorrecteds first. If the
CMs are not going offline (Ins = 0), this will
not be noticed by the subscriber. However,
they could receive slower service due to
dropped IP packets in the upstream. This
condition will also result in input errors on
the cable interface.
High insertion rate. If link re-establishment happens too
frequently, then the CM is usually having a
registration problem.This is indicated by a
high ‘Ins’ counter which tracks the ‘Flap’
counter.
Note: CMs go offline faster than the frequency hop period and can cause
the frequency to stay fixed while CMs go offline. Reduce the hop period to
10 seconds to adjust to the hop frequency period.
Table 4-2 Troubleshooting CM Problems
Cause or Symptom Problem