Troubleshooting guide

5-18
ATM and Layer 3 Switch Router Troubleshooting Guide
OL-1969-02
Chapter 5 Troubleshooting Switch Router ATM Interface Connections
Common show controller Troubleshooting Fields
Table 5-4 explains Line coding errors displayed in the output of the show controllers atm command.
Note All parameters are accumulated in 15-minute intervals, and up to 96 intervals (24 hours worth) are
kept by the ATM switch router. Fewer than 96 intervals of data are available if the ATM switch router
has restarted within the last 24 hours. In addition, each performance parameter has a rolling 24-hour
total.
Table 5-2 show controller Display Facilities Statistics and Explanations
Facility Statistic Explanation Recommendation
Line Code Violation
(LCV)
Indicate the number of bipolar violation (BPV) or
excessive zeros (EXZ) errors. The conditions that
cause this error to increment will vary with the line
coding.
Bipolar violation:
AMI—Receiving two successive pulses of the
same polarity.
B3ZS or HDB3—Receiving two successive pulses
of the same polarity, but these pulses are not part
of zero substitution.
Excessive zeros:
AMI—Receiving more than 15 contiguous zeros.
B3ZS—Receiving more than seven contiguous
zeros.
Framing Bit Error
(BE)
Indicate the number of times that an incorrect
pattern for the F1-to-F4 framing bits was detected.
Summed Excessive
Zeros (EZD)
Indicate the number of times that an “excessive”
number of adjacent binary zeros was detected.
Excessive is defined as greater than three zeros for
B3ZS and greater than four zeros for HDB3.