output drops on fastethernet not saturated. - Page 2

s.balon · ‎09-14-2010

Hi,

We had a Cisco 3750 with a interface that encounter output drop .

We change the cable, we change the interface.

The traffic have the same bandwidth pattern since a long time but now we have output drop.

We try to increase the output hold queue but with the same result.

It's a 100Mbps Full duplex Lease line.

sh int gi 2/0/10
GigabitEthernet2/0/10 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is xxxx.xxxx.xxxx
MTU 1528 bytes, BW 100000 Kbit, DLY 100 usec,
     reliability 255/255, txload 139/255, rxload 56/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is 10/100/1000BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 9w4d, output 00:00:56, output hang never
Last clearing of "show interface" counters 00:03:53
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 25824
Queueing strategy: fifo
Output queue: 0/100 (size/max)
30 second input rate 22006000 bits/sec, 11820 packets/sec
30 second output rate 65047000 bits/sec, 14305 packets/sec
     2506589 packets input, 573262613 bytes, 0 no buffer
     Received 496 broadcasts (495 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 495 multicast, 0 pause input
     0 input packets with dribble condition detected
     3096893 packets output, 1729579549 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 PAUSE output
     0 output buffer failures, 0 output buffers swapped out

Does someone have a idea ?

What can cause output drops except saturation.

Thanks for your help.

francisco_1 · ‎09-16-2010

Have you tried enabling flow control on both side to exchange paue frame to help with the conjestion?

Francisco.

s.balon · ‎09-17-2010

Hi,

We have effectivly try with flowcontrol but we had the same issue.

Today we have connect a new switch behind the stack

a 3560G.

We put a gigabit trunk between the stack and this new switch.

We migrate the link to this new switch..

And.... tada.. no more drop....

So we have definitvly a issue with the stack.

I have put on the flash of the stack to the last ios version available and we need to schedule a reboot.

If we still had packet drop on the stack, we will go for a RMA I think.

If you have any oher idea... you welcome :-).

Thanks all for your help.

Steve

s.balon · ‎09-30-2010

Hi,

The upgrade has been performed and the switch reboot...

But We still have the same issue with the packets drop.

The latest test is to remove one switch from the stack and test it in stand alone.

We are very stuck.

Why we have the same problem on the 2 switch in the stack ?

Have a nice day.

Steve