How to reduce or eliminate output queue drop?

Santosh Shetty · ‎10-21-2014

Getting outpug queue drop on router

Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 38827
Queueing strategy: Class-based queueing
Output queue: 0/40 (size/max)
1 minute input rate 11256000 bits/sec, 3444 packets/sec
1 minute output rate 19425000 bits/sec, 3882 packets/sec

We get queue drop even when link utlization is low. RX, TX 10%.

Joseph W. Doherty · ‎10-21-2014

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If cause of your drops are because of transient bursts, increasing egress queue limit might mitigate.

PS:

BTW, "low" link utilization doesn't preclude having queue drops. Conversely you can have 100% utilization with no drops and no egress queue.

Carlos de Armas · ‎10-21-2014

Hello,

Check the output queue size and if you have any QoS that could be the cause.

Also you might want to take a look to this doc:

http://www.cisco.com/c/en/us/support/docs/routers/10000-series-routers/6343-queue-drops.html

Regards