output drops other than by RED

[paul amaral]

if using RED/WRED for congestion what else would cause output drops. i ask because i have a higher number of total output drops than I do with RED drops. Basically why im I not seeing the other drops, supposedly i have 719 drops but only 421 by RED, what caused the other drops.

Also in this case with late drops I'm assuming this is the typical congested output queue and WRED removed all non important packets.

thanks for your time, Paul

Serial8/1/1 is up, line protocol is up

  Hardware is PODS3 Serial

  MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,

     reliability 255/255, txload 40/255, rxload 38/255

  Encapsulation PPP, crc 16, loopback not set

Input queue: 0/75/0/7 (size/max/drops/flushes); Total output drops: 719

  Queueing strategy: Class-based queueing

  Output queue: 0/40 (size/max)

  30 second input rate 6702000 bits/sec, 1753 packets/sec

  30 second output rate 6978000 bits/sec, 1797 packets/sec

     50404534 packets input, 26804686540 bytes, 0 no buffer

     Received 0 broadcasts (0 IP multicasts)

     0 runts, 0 giants, 0 throttles

              0 parity

     9722 input errors, 9710 CRC, 0 frame, 3 overrun, 0 ignored, 9 abort

     53762996 packets output, 29151563718 bytes, 0 underruns

     421 packets late drop, 543133 bytes late drop

     0 output errors, 0 applique, 0 interface resets

     0 output buffer failures, 0 output buffers swapped out

     2 carrier transitions

sh int xx random

Class 0 queue size 0

       packets output 44386011, wred drops 421, nobuffer drops 0

WRED: queue average 0, weight 1/512, max available buffers 4973

[Joseph W. Doherty]

Disclaimer

The  Author of this posting offers the information contained within this  posting without consideration and with the reader's understanding that  there's no implied or expressed suitability or fitness for any purpose.  Information provided is for informational purposes only and should not  be construed as rendering professional advice of any kind. Usage of this  posting's information is solely at reader's own risk.

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Posting

Might be wred drops don't include RED tail drops or non-RED queue drops.

What's show policy interface stats look like?

[paul amaral]

The show policy-map int xxx shows only random drops that are 421 (less than total output drops) and tail drops at zero. what constitutes and non RED queue drop, i would think on a 44 meg serial interface doing an average of 10 megs a congestion mechanism like RED would drop all packets before the queue got congested, i guess that maybe im getting some spikes in bandwidth that RED is not keeping up!?

Paul

[Joseph W. Doherty]

Disclaimer

The   Author of this posting offers the information contained within this   posting without consideration and with the reader's understanding that   there's no implied or expressed suitability or fitness for any purpose.   Information provided is for informational purposes only and should not   be construed as rendering professional advice of any kind. Usage of  this  posting's information is solely at reader's own risk.

Liability Disclaimer

In   no event shall Author be liable for any damages whatsoever (including,   without limitation, damages for loss of use, data or profit) arising  out  of the use or inability to use the posting's information even if  Author  has been advised of the possibility of such damage.

Posting

I'm not positive WRED always replaces the original queue with its own queue.  It might help if you posted the show policy interfaces stats.

[paul amaral]

I think i figured out why i was seeing more drops reported with sh int xxx than with show policy-map int xxx. Looking at the router log i notice that the interface bounce a couple of times and this must of dropped all packets in the outgoing queue that were no WRED dropped.