Alaxala AX2500S, Troubleshooting Manual

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3 Troubleshooting Functional Failures During Operation
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3.15 Communication failures in filtering and QoS configurations
3.15.1 Checking the filtering and QoS control configuration information
If a communication problem occurs on a network employing the Switch, it is possible that
certain packets have been discarded either by filtering or by the QoS control shaper.
To determine which functionality discarded which packets when packets have been
discarded in the Switch by filtering and QoS control, do the following.
(1) Checking whether packets have been discarded by filtering
1. Log in to the Switch.
2. Execute the show access-filter operation command, and check the filtering
conditions in the access list applied to the interface, the number of packets that
match the filtering conditions, and the number of packets discarded by a filter entry
for implicit discard.
3. Compare the filtering conditions you checked in step 2 and the contents of the
packets that cannot be forwarded to determine whether the target packets were
discarded. If the contents of the packets that cannot be forwarded do not match any
of the applied filtering conditions, the packets might have been discarded implicitly.
4. Check whether the setting conditions in the filtering configuration are correct.
(2) Checking whether packets have been discarded by the QoS control shaper
1. Log in to the Switch.
2. Use the show qos queueing operation command to check the information displayed
for
discard packets
in the output interface statistics.
3. Check whether the shaper is being used appropriately in the system configuration.