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fsm Beginner
Beginner

GigabitEthernet is down, line protocol is down (notconnect)

Hi all,

I've got a problem with some sfps which status are "GigabitEthernet is down, line protocol is down (notconnect)"

I've got the impression that this is a problem with the hardware (either the sfps or the fibers between them) since configuration wise it looks OK, but I would like your opinion to rule out any configuration problems or something I've missed, before ordering more hardware.

I can provide more info if necessary

 

The setup:

2 stacks of 3 switches (6 in total, 12 sfps)

Port-channel between these stacks are always on port gx/0/51 and gx/0/52

On all 6 switches, ios is the same

Cisco IOS Software, C2960X Software (C2960X-UNIVERSALK9-M), Version 15.2(6)E1, RELEASE SOFTWARE (fc4)

Port-channel is mode "on" on all switches

 

The problem:

Out of 12 sfps, only 4 are working

No lights on the non working ones and if I run the command "show int gx/y/z" this is the output

 

SW-S02#show int g1/0/51

GigabitEthernet1/0/51 is down, line protocol is down (notconnect)

  Hardware is Gigabit Ethernet, address is 003c.1093.f533 (bia 003c.1093.f533)

  Description: SW-02 UPlink to SW-01

  MTU 1500 bytes, BW 10000 Kbit/sec, DLY 1000 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 SFP

  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 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 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 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

     0 packets output, 0 bytes, 0 underruns

     0 output errors, 0 collisions, 4 interface resets

     0 unknown protocol drops

     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

 

More info:

Ports are connected as such. Example

SW01 1/0/51==>SW02 1/0/51

But since the person who setup the stack did not force priorities and such the stack looks like the following

SW01

SW02

1

3

2

2

3

1

 

So logically

SW01 1/0/51==>SW02 3/0/51

 

 

Under show inventory, all sfps'a are recognized by the switch. Example

 

SW-S02#show inventory

 

NAME: "GigabitEthernet1/0/51", DESCR: "1000BaseLX SFP"

PID: GLC-LH-SMD          , VID: V01  , SN: LEG3A91D9036 

 

This is the output os sh int status

 

SW-S02#show int g1/0/51 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi1/0/51  SW-02 UPlink t notconnect   1            auto   auto 1000BaseLX SFP

SW-S02#show int g1/0/52 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi1/0/52  SW-S02 UPlink  notconnect   1            auto   auto 1000BaseLX SFP

SW-S02#show int g2/0/51 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi2/0/51  SW-02 UPlink t notconnect   1            auto   auto 1000BaseLX SFP

SW-S02#show int g2/0/52 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi2/0/52  SW-S02 UPlink  connected    trunk      a-full a-1000 1000BaseLX SFP

SW-S02#show int g3/0/51 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi3/0/51  SW-02 UPlink t notconnect   1            auto   auto 1000BaseLX SFP

SW-S02#show int g3/0/52 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi3/0/52  SW-S02 UPlink  connected    trunk      a-full a-1000 1000BaseLX SFP

SW-S02#

 

SW-S01#show int g1/0/51 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi1/0/51  SW-S01         notconnect   1            auto   auto 1000BaseLX SFP

SW-S01#show int g1/0/52 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi1/0/52  SW-S01         connected    trunk      a-full a-1000 1000BaseLX SFP

SW-S01#show int g2/0/51 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi2/0/51  SW-01          notconnect   1            auto   auto 1000BaseLX SFP

SW-S01#show int g2/0/52 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi2/0/52  SW-S01         connected    trunk      a-full a-1000 1000BaseLX SFP

SW-S01#show int g3/0/51 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi3/0/51  SW-01          notconnect   1            auto   auto 1000BaseLX SFP

SW-S01#show int g3/0/52 status

 

Port      Name               Status       Vlan       Duplex  Speed Type

Gi3/0/52  SW-S01         notconnect   1            auto   auto 1000BaseLX SFP

SW-S01#

 

Confiuration of these ports

 

SW-S02#show run int g1/0/51

Building configuration...

 

Current configuration : 130 bytes

!

interface GigabitEthernet1/0/51

 description SW-02 UPlink to SW-01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S02#show run int g1/0/52

Building configuration...

 

Current configuration : 132 bytes

!

interface GigabitEthernet1/0/52

 description SW-S02 UPlink to SW-S01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S02#show run int g2/0/51

Building configuration...

 

Current configuration : 130 bytes

!

interface GigabitEthernet2/0/51

 description SW-02 UPlink to SW-01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S02#show run int g2/0/52

Building configuration...

 

Current configuration : 151 bytes

!

interface GigabitEthernet2/0/52

 description SW-S02 UPlink to SW-S01

 switchport mode trunk

 downshift disable

 channel-group 1 mode on

end

 

SW-S02#show run int g3/0/51

Building configuration...

 

Current configuration : 130 bytes

!

interface GigabitEthernet3/0/51

 description SW-02 UPlink to SW-01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S02#show run int g3/0/52

Building configuration...

 

Current configuration : 132 bytes

!

interface GigabitEthernet3/0/52

 description SW-S02 UPlink to SW-S01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S02#show run in port-channel 1

Building configuration...

 

Current configuration : 99 bytes

!

interface Port-channel1

 description SW-S02 UPlink to SW-S01

 switchport mode trunk

end

 

 

SW-S01#show run int g1/0/51

Building configuration...

 

Current configuration : 111 bytes

!

interface GigabitEthernet1/0/51

 description SW-S01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S01#show run int g1/0/52

Building configuration...

 

Current configuration : 111 bytes

!

interface GigabitEthernet1/0/52

 description SW-S01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S01#show run int g2/0/51

Building configuration...

 

Current configuration : 110 bytes

!

interface GigabitEthernet2/0/51

 description SW-01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S01#show run int g2/0/52

Building configuration...

 

Current configuration : 111 bytes

!

interface GigabitEthernet2/0/52

 description SW-S01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S01#show run int g3/0/51

Building configuration...

 

Current configuration : 110 bytes

!

interface GigabitEthernet3/0/51

 description SW-01

 switchport mode trunk

 channel-group 1 mode on

end

 

SW-S01#show run int g3/0/52

Building configuration...

 

Current configuration : 111 bytes

!

interface GigabitEthernet3/0/52

 description SW-S01

 switchport mode trunk

 channel-group 1 mode on

end

 

 

SW-S01#show run int port-channel 1

Building configuration...

 

Current configuration : 78 bytes

!

interface Port-channel1

 description SW-S01

 switchport mode trunk

end

 

Show ip int brief (edited)

 

SW-S02#show ip int brief

Interface              IP-Address      OK? Method Status                Protocol

GigabitEthernet1/0/51  unassigned      YES unset  down                  down   

GigabitEthernet1/0/52  unassigned      YES unset  down                  down   

GigabitEthernet2/0/51  unassigned      YES unset  down                  down   

GigabitEthernet2/0/52  unassigned      YES unset  up                    up     

GigabitEthernet3/0/51  unassigned      YES unset  down                  down   

GigabitEthernet3/0/52  unassigned      YES unset  up                    up     

Port-channel1          unassigned      YES unset  up                    up     

 

SW-S01#show ip int brief

Interface              IP-Address      OK? Method Status                Protocol

GigabitEthernet1/0/51  unassigned      YES unset  down                  down   

GigabitEthernet1/0/52  unassigned      YES unset  up                    up     

GigabitEthernet2/0/51  unassigned      YES unset  down                  down   

GigabitEthernet2/0/52  unassigned      YES unset  up                    up     

GigabitEthernet3/0/51  unassigned      YES unset  down                  down   

GigabitEthernet3/0/52  unassigned      YES unset  down                  down   

Port-channel1          unassigned      YES unset  up                    up     

1 ACCEPTED SOLUTION

Accepted Solutions
VIP Advisor

Re: GigabitEthernet is down, line protocol is down (notconnect)

it should just work after issuing the command , the command is non service effecting it wont break anything , it will just allow 3rd party sfps to work

the fact 4 of the sfps work it may not be the issue , if it was software/hardware blocking them as unsupported they would block the 12 of them not just some of them

Did you try cross the fibres over at one end ,the tx/rx yet
20 REPLIES
VIP Advisor

Re: GigabitEthernet is down, line protocol is down (notconnect)

Hi
have you tried to hardcode the speed under the interfaces ?

the port is physically down so you have some form of Layer 1 issue , either SFPs or fibre cable itself
Have you tried split the pairs at one end , incase the tx and rx are back to front , basically cross them over

ther long range SFPs are you connecting between buildings or long distances , what is the fibre type cable your using ?

Its not a config issue id say as it hasnt even got layer 1 up yet , is there any difference between the fibre cabling or sfps on the 4 working connections ?

fsm Beginner
Beginner

Re: GigabitEthernet is down, line protocol is down (notconnect)

Thanks for the reply Mark.

"have you tried to hardcode the speed under the interfaces ?"

I haven't tried it yet. Will do and keep you posted.

"ther long range SFPs are you connecting between buildings or long distances , what is the fibre type cable your using ?"

No, in fact It's connecting two floors. I also found it strange that long range has been used since there's tops 100 meters between the two cabinets. Unfortunatelly I had no say when the whole installation was done, and it was done in a rush (by a professional company). I don't know exactly the fibre type, I know it's monomode and the cables are pairs.

"Its not a config issue id say as it hasnt even got layer 1 up yet , is there any difference between the fibre cabling or sfps on the 4 working connections ?"

Afaik there's no difference on the cabling, which has been done by a professional company and tested. I'm wondering about the sfps though, since they're Legrand brand. I would like to remove one of the working sfps to verify and make sure they're also of the same brand, but I'm afraid that by plugging it back it will give me the same error as the others.

fsm Beginner
Beginner

Re: GigabitEthernet is down, line protocol is down (notconnect)

Mark,

I cannot change the speed

 

SW-S01(config)#int g3/0/51
SW-S01(config-if)#speed ?
% Unrecognized command

Highlighted
VIP Advisor

Re: GigabitEthernet is down, line protocol is down (notconnect)

yes sorry that was my early morning brain , you cant alter speed on fibre it should just pick it up
Only works for copper
VIP Advisor

Re: GigabitEthernet is down, line protocol is down (notconnect)

Yes there not really the correct sfps for that , a standard 1 GB sfp would be alot cheaper and work fine

 

If there not Cisco and there Legrand brand. then add what George has stated incase its having issues reading them , there unsupported as far as the switch may see them as there not cisco , most 3rd party brands do work but a lot dont either and it can be the difference of a version number on the back of the sfp

 

you can see the SFP type with show int gx/x transciever

 

 they may need to be crossed over protection or not on the cable , they should pop out of the protection clip and be able to be changed around , all standard fiber cables usually can

 

do you have any Cisco sfps you could test with instead to rule out the Legrand brand ? even some GLC-MM-SX ones

 

VIP Mentor

Re: GigabitEthernet is down, line protocol is down (notconnect)

Hello,

 

on a side note, and in addition to Mark's remarks, there is a remote chance that globally configuring 'service unsupported-transceiver' gets the SFPs up...

 

Switch(config)# service unsupported-transceiver.

fsm Beginner
Beginner

Re: GigabitEthernet is down, line protocol is down (notconnect)

Thanks for the reply Georg.

I thought about this but I don't know if this will have any negative impact on the working ones, since they're recognized and working.

VIP Mentor

Re: GigabitEthernet is down, line protocol is down (notconnect)

Hello,

 

you can configure this, it won't affect the existing, working SFPs...

fsm Beginner
Beginner

Re: GigabitEthernet is down, line protocol is down (notconnect)

Georg,

Ebverything is pointing to the direction of the sfps not being supported.

We will turn on globally the service-unsupported transceiver today on the two switch stacks.

I have used this command in the past on a lab environment and I don't remember if I had to shut-no shut the interfaces, reboot the devices or if it just worked after issuing the command.

Can you please give your opinion on how I should go about this?

I'll let you know once done, looks like you gave the solution :-)

VIP Advisor

Re: GigabitEthernet is down, line protocol is down (notconnect)

it should just work after issuing the command , the command is non service effecting it wont break anything , it will just allow 3rd party sfps to work

the fact 4 of the sfps work it may not be the issue , if it was software/hardware blocking them as unsupported they would block the 12 of them not just some of them

Did you try cross the fibres over at one end ,the tx/rx yet
fsm Beginner
Beginner

Re: GigabitEthernet is down, line protocol is down (notconnect)

Thanks for the swiftly reply Mark.

In fact while checking the sfps closelly, we saw that the 4 working ones are different from the other 8... So I'm guessing that they're Cisco brand (although I cannot confirm, since there's prod traffcic going through them we did not plug them out, but externally they look different).

I'll let you know but in any case many thanks for the help!

VIP Advisor

Re: GigabitEthernet is down, line protocol is down (notconnect)

Ah ok that may be the issue then good luck
Contributor

Re: GigabitEthernet is down, line protocol is down (notconnect)

Try the command "sh idprom interface gix/y"

in the output may occur "Vendor Name : OEM"

compare output from working and non-working SFP's

fsm Beginner
Beginner

Re: GigabitEthernet is down, line protocol is down (notconnect)

Hi,
we had to cross the fibers after the service-unsupported transceiver did not work.
After the fiber rx and tx were crossed in one end the interfaces started coming up.
Thank you very much for your help
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