Output Drops on Cisco Switch -- Counter?

Question

I was always under the impression that the Total output drops was a counter that goes up until it resets (or maybe wraps around 4 billion).

However, this seems to indicate otherwise, or something is just messed up:

ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 14456
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 7228
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 7228
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3614

Another Sample:

ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3636
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 3636
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908
ny-swstack01#show int GigabitEthernet2/0/25 | inc Total output drops
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 10908

In both of these examples I am just running the command over and over again, ~ second or so between commands.

What's your IOS version on these switches? They're 2960's, aren't they? — Evan Anderson, Jul 12 '11 at 20:53
@Evan: 12.2(53r)SE -- we just updated this weekend because they seem to destabilize every two weeks, and they wouldn't show proper CPU usage unless you had a console session open. — Kyle Brandt, Jul 12 '11 at 20:56

score 2 · Accepted Answer · edited Aug 09 '11 at 17:48

2

This is a bug in the IOS version you are using and is filed under CSCtq86186. Run a show interface counter error and see out the outDiscards looks there. It's got me scratching my head.

edited Aug 09 '11 at 17:48

Kyle Brandt

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answered Jul 12 '11 at 21:07

Evan Anderson

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That seems to imply that it shows ASIC drops -- which doesn't really make sense because this goes up and down – Kyle Brandt Jul 12 '11 at 21:18
That command reports 3673 consistently it seems. – Kyle Brandt Jul 12 '11 at 21:18
Bug is filed as CSCtq86186 – Kyle Brandt Aug 01 '11 at 17:58

Output Drops on Cisco Switch -- Counter?

1 Answers1