2950 and Fibre connections

Switches in the same cabinet... is it possible that there is already a logical link between the two, and that when you are adding the fibre connection that the spanning tree algorithm is kicking in and disabling the fibe link?

Sorry for the delay Walter, the main link between the 2 switches is normally via a ethernet port but when i am attempting to try this out the cable has been unplugged so the only exisiting link is that of the fibre - Are there any more ideas please as this is driving me mad :)

The fiber port IS an Ethernet port. So:- if you make the confguration of the fiber and copper ports the same _except_ for speed/duplex settings then you should be in business.

For Gigabit do not use Speed/Duplex settings.

i dont quite understand what you mean there so have copied in the relevant parts of the config files interface Port-channel1 switchport mode trunk no ip address ! interface FastEthernet0/1 description ****** switchport mode trunk no ip address ... ... interface GigabitEthernet0/1 description *** *** switchport mode trunk no ip address channel-group 1 mode on ! interface GigabitEthernet0/2 description *** *** switchport mode trunk no ip address channel-group 1 mode on

It is similar on both switches and the connection works fine across cabinets just seems to fail locally.

thanks

What type of GBICs are being used ?

Is the minimum fiber cable distance of 6.5 ft being respected ?

Try using the longest patch cable available

the gbics are 1000base-sx gbics. The fibre cables between the switches is only a maximum 2m. differant cables have been tried

Start from the beginning.

Are the interfaces coming up?

CORE1#sh int gi 1/1 GigabitEthernet1/1 is up, line protocol is up (connected)

If not then you have a physical layer issue. e.g.

Are the ports err-disable?

shut then "no shut" to remove err-disable.

Are you using an appropriate fiber?

The fiber you need is 62.5/125 or 50/125 micron core. NOT 8.5/125 or

9/125 micron core. The fiber is usully marked periodically along its length with the Inner/Outer core diameter.

You CLEARLY have to connect the Transmitter on one side to the Receiver on the other side. Check that this is the case. The Right hand port on one switch should go to the left hand one on the other.

I have not used many GBICs for a while but they used to be pretty unreliable.

If the switched have more than one GBIC port you could put them both in

each switch in turn and check if it works that way.

Fibers that look damaged are probably scrap. They should be stored with the ends protected from abrasion and dirt/dust.

post sh int sh int trunk sh etherchannel

The interfaces when connected do come up live i believe the err-disable is off and the fibre is 62.5/125. As suggested above the ports are connected up as you suggest with the rhs of the top switch going to the lhs of the bottom switch. As requested here are edited versions of the files

int :

GigabitEthernet0/1 is up, line protocol is up (connected) Hardware is Gigabit Ethernet, address is 000f.34e3.50d9 (bia

000f.34e3.50d9) Description: *** *** MTU 1500 bytes, BW 1000000 Kbit, DLY 1000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 1000Mb/s, link type is auto, media type is SX output flow-control is on, input flow-control is off ARP type: ARPA, ARP Timeout 04:00:00 Last input 00:00:22, output 00:00:06, output hang never Last clearing of "show interface" counters never 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 1487000 bits/sec, 191 packets/sec 5 minute output rate 207000 bits/sec, 140 packets/sec 52347378 packets input, 3517655132 bytes, 0 no buffer Received 5805082 broadcasts (0 multicast) 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 3318076 multicast, 0 pause input 0 input packets with dribble condition detected 44840744 packets output, 3438110220 bytes, 0 underruns 0 output errors, 0 collisions, 2 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 GigabitEthernet0/2 is up, line protocol is up (connected) Hardware is Gigabit Ethernet, address is 000f.34e3.50da (bia 000f.34e3.50da) Description: *** *** MTU 1500 bytes, BW 1000000 Kbit, DLY 1000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 1000Mb/s, link type is auto, media type is SX output flow-control is on, input flow-control is off ARP type: ARPA, ARP Timeout 04:00:00 Last input 00:00:22, output 00:00:06, output hang never Last clearing of "show interface" counters never 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 1216000 bits/sec, 275 packets/sec 5 minute output rate 699000 bits/sec, 223 packets/sec 60901726 packets input, 1416495495 bytes, 0 no buffer Received 1380340 broadcasts (0 multicast) 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 51529 multicast, 0 pause input 0 input packets with dribble condition detected 58637153 packets output, 3780763984 bytes, 0 underruns 0 output errors, 0 collisions, 2 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 Port-channel1 is up, line protocol is up (connected) Hardware is EtherChannel, address is 000f.34e3.50d9 (bia 000f.34e3.50d9) MTU 1500 bytes, BW 2000000 Kbit, DLY 1000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Full-duplex, 1000Mb/s input flow-control is off, output flow-control is off Members in this channel: Gi0/1 Gi0/2 ARP type: ARPA, ARP Timeout 04:00:00 Last input 00:00:01, output never, output hang never Last clearing of "show interface" counters never 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 2737000 bits/sec, 474 packets/sec 5 minute output rate 947000 bits/sec, 377 packets/sec 113249094 packets input, 639182691 bytes, 0 no buffer Received 7185414 broadcasts (0 multicast) 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 3369597 multicast, 0 pause input 0 input packets with dribble condition detected 103477886 packets output, 2923906204 bytes, 0 underruns 0 output errors, 0 collisions, 1 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

int trunk :

2950CabB#sh int trunk

Port Mode Encapsulation Status Native vlan Fa0/1 on 802.1q trunking 1 Po1 on 802.1q trunking 1

Port Vlans allowed on trunk Fa0/1 1-4094 Po1 1-4094

Port Vlans allowed and active in management domain Fa0/1 1-2,6,10-11,30 Po1 1-2,6,10-11,30

Port Vlans in spanning tree forwarding state and not pruned Fa0/1 1-2,6,10-11,30 Po1 1-2,6,10-11,30

sh etherchannel : Channel-group listing: -----------------------

Group: 1

---------- Group state = L2 Ports: 2 Maxports = 8 Port-channels: 1 Max Port-channels = Protocol: -

Any help again is appreciated but i will be away for the next week so will be a little slow in replying .

Many many thanks Phil