[c-nsp] WS-X6348-RJ-45 and Output drops

[Robert Hass]

Hi

I have installed WS-X6348-RJ-45 card in Catalyst 6500/Sup32 and I saw
increasing output drops on each FE interface. Currently I'm using only 3
ports on this card (Fa1/1, Fa1/2, Fa1/48). Avarage traffic level on each
port is about 10-20Mbps. I also didn't saw large traffic peaks like >80Mb on
MRTG graphs (with WithPeak option switched-on) of these ports.

So, what causing Output drops on this card ?

Here is output of show interface:
FastEthernet1/1 is up, line protocol is up (connected)
  Hardware is C6k 100Mb 802.3, address is 0001.c96a.8e84 (bia 0001.c96a.8e84)
  Description: Customer DataTech
  MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
     reliability 255/255, txload 31/255, rxload 65/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 100Mb/s
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output never, output hang never
  Last clearing of "show interface" counters 7w3d
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 19674562
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  30 second input rate 25559000 bits/sec, 10902 packets/sec
  30 second output rate 12205000 bits/sec, 13481 packets/sec
     24149904901 packets input, 10099290976969 bytes, 0 no buffer
     Received 7617 broadcasts (7617 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
     29324673054 packets output, 3831810881262 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

FastEthernet1/48 is up, line protocol is up (connected)
  Hardware is C6k 100Mb 802.3, address is 0001.c96a.8e86 (bia 0001.c96a.8e86)
  Description: sw3
  MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
     reliability 255/255, txload 105/255, rxload 51/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 100Mb/s
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output never, output hang never
  Last clearing of "show interface" counters 7w3d
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 2032436
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  30 second input rate 20003000 bits/sec, 6993 packets/sec
  30 second output rate 41324000 bits/sec, 7807 packets/sec
     25171862715 packets input, 9131681778867 bytes, 0 no buffer
     Received 493121 broadcasts (160311 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
     28744492098 packets output, 19704727289126 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

interface FastEthernet1/1
 description Customer DataTech
 switchport
 switchport access vlan 604
 switchport mode access
 no ip address
 logging event link-status
 load-interval 30
 no cdp enable
 spanning-tree portfast
 spanning-tree bpdufilter enable
!
interface FastEthernet1/2
 description MGMT SDH
 switchport
 switchport access vlan 2150
 switchport mode access
 no ip address
 logging event link-status
 load-interval 30
 speed 10
 no cdp enable
 spanning-tree portfast
!
...
interface FastEthernet1/48
 description sw3
 switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 136,338,622,1810
 switchport mode trunk
 switchport nonegotiate
 no ip address
 logging event link-status
 logging event bundle-status
 logging event trunk-status
 load-interval 30
 speed 100
 duplex full
 no cdp enable
 spanning-tree portfast trunk
 spanning-tree bpdufilter enable
!

Thanks,
Robert