[c-nsp] LX GBIC at half duplex?

[Jason Lixfeld]

Hi all,

Running up against an odd issue where we have a 3550 with an LX GBIC trying to talk to a copper port on an ME3600 with a media converter in the middle.  The ME3600 side always shows as up; we disabled fault passthrough on the MC.  The LX GBIC on the 3550 side shows down/down with negotiation enabled, so with negotiation disabled, it shows up/up, but at half duplex(?!).  Anyone seen this before?  I didn't think an LX GBIC at half duplex was possible, even with negotiation disabled as there is still no way to force the duplex in that state.  Bad GBIC?  Media converter borked?  Gremlins?

I'd be grateful for any insight gleaned from prior experiences..

Thanks in advance.

For completeness:

Model number: WS-C3550-24-SMI
System image file is "flash:c3550-ipservicesk9-mz.122-35.SE5.bin"

TOYF-1.10-1.A920#show int g0/1
GigabitEthernet0/1 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is 0014.6aa4.0c00 (bia 0014.6aa4.0c00)
  Description: Facing gi0-24.pe01.171EastLibertySt01.YYZ
  Internet address is 1.1.1.1/30
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, 
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive not set
  Half-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseLX
  input flow-control is off, output flow-control is on 
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 23:14:46, output 00:00:02, output hang never
  Last clearing of "show interface" counters 06:02:06
  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 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 144492 bytes, 0 no buffer
     Received 0 broadcasts (0 IP 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
     326 packets output, 122306 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
TOYF-1.10-1.A920#sh run int g0/1
Building configuration...

Current configuration : 167 bytes
!
interface GigabitEthernet0/1
 no switchport
 ip address 1.1.1.1 255.255.255.252
 speed nonegotiate
end

TOYF-1.10-1.A920#show mac address-table int g0/1
          Mac Address Table
-------------------------------------------

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
TOYF-1.10-1.A920#

.........


TOYF-1.10-1.A920#sh int g0/1
GigabitEthernet0/1 is down, line protocol is down (notconnect)
  Hardware is Gigabit Ethernet, address is 0014.6aa4.0c00 (bia 0014.6aa4.0c00)
  Description: Facing gi0-24.pe01.171EastLibertySt01.YYZ
  Internet address is 1.1.1.1/30
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, 
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive not set
  Auto-duplex, Auto-speed, link type is auto, media type is 1000BaseLX
  input flow-control is off, output flow-control is on 
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 23:18:01, output 00:00:18, output hang never
  Last clearing of "show interface" counters 00:00:32
  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 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 0 bytes, 0 no buffer
     Received 0 broadcasts (0 IP 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
     4 packets output, 1210 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
TOYF-1.10-1.A920#sh run int g0/1
Building configuration...

Current configuration : 148 bytes
!
interface GigabitEthernet0/1
 description Facing gi0-24.pe01.171EastLibertySt01.YYZ
 no switchport
 ip address 1.1.1.1 255.255.255.252
end

TOYF-1.10-1.A920#