[c-nsp] Switchport has high Total output drops

[Ruben Alvarez]

Hi All,

I have a Catalyst 6509 FE port with a high level of total output drops.  It
is connected to a 3640 router with an 10M Eth port.  It looks like there is
about 5Mbps of traffic being dropped at the switch interface.  I did an RX
and TX packet capture at the switch port.  The RX was normal with very
normal traffic coming from the router.  The TX traffic included much more
traffic that shouldn't be seen on that port.  I would think POP And SMTP
destine for other IP addresses in the network would not show on that
capture.  I've already cleared ARP and checked to make sure no incorrect
routes were destine for that router.  Anyone have any ideas?

Thanks.

Cat6509#
FastEthernet8/39 is up, line protocol is up (connected)
  Hardware is C6k 100Mb 802.3, address is 000f.233e.1e96 (bia
000f.233e.1e96)
  MTU 1500 bytes, BW 10240 Kbit, DLY 100 usec,
     reliability 255/255, txload 140/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 10Mb/s
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:55, output never, output hang never
  Last clearing of "show interface" counters 00:08:00
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops:
119053
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 53000 bits/sec, 59 packets/sec
  5 minute output rate 5643000 bits/sec, 1303 packets/sec
     31232 packets input, 3119120 bytes, 0 no buffer
     Received 79 broadcasts (79 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 0 multicast, 0 pause input
     0 input packets with dribble condition detected
     604547 packets output, 340450837 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

3640router#
Ethernet0/0 is up, line protocol is up
  Hardware is AmdP2, address is 0030.94b3.8701 (bia 0030.94b3.8701)
  Internet address is 192.168.1.20/24
  MTU 1500 bytes, BW 10240 Kbit, DLY 1000 usec,
     reliability 255/255, txload 1/255, rxload 9/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters 00:08:26
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 375000 bits/sec, 66 packets/sec
  5 minute output rate 42000 bits/sec, 58 packets/sec
     38798 packets input, 28866998 bytes, 0 no buffer
     Received 1309 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 input packets with dribble condition detected
     32136 packets output, 3014355 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 output buffer failures, 0 output buffers swapped out