01-11-2019 03:17 AM - edited 03-08-2019 05:00 PM
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
Solved! Go to Solution.
01-14-2019 05:01 AM
Hello,
what was the solution to this ?
01-14-2019 05:05 AM
we issued the service-unsupported transceiver and it did not work so we switched the rx/tx on the non working ones and they started coming up.
Now I still have doubts since 4/12 are Legrand brand and the 4 ones that originally worked are of some other brand (probably Cisco) so perhaps the command was necessary but the problem was indeed the cabling.
01-11-2019 03:43 AM
Your port channel configurations are configured correctly, the fact that your device is detecting each sfp module I would move to look at the media that is connecting the switches together, have you tried switching the fiber cables around by using the pairs that are confirmed to be working to the non working ports?.I would definitely recommend that to see if you have some bad fiber pairs in the mix before looking at the sfp as an issue.
01-11-2019 04:19 AM
Thanks for the reply Patrick.
Switching the ends was my first though but the connectors have some sort of protection that does not let me switch the ends.
Usually, when I have any problem of the sort, switching the ends would be my first troubleshooting step, as everything seems to be pointing to a hardware problem (either sfp or fibers).
01-11-2019 06:08 AM
01-11-2019 06:06 AM
Hi,
The SFP is recognised by the switch and configuration looks OK. Common problem is fibre patch leads. Have you checked the fibre cables to make sure transmit is going to receive.
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