08-18-2022 01:20 PM
Hello,
Recently some of switches I have has been shown faulty issue on Fiber port.
I have seen this kind of issue on both '3750X series and 2960X series', and issue is following:
- Swithes are 48- Ethernet ports PoE + 4 Fiber ports
- 3750X switch = 3/4 ports are currently plugged with Cisco GBIC module.
2960X switch = 1/4 port is currently plugged with Cisco GBIC module.
- I plugged new Fiber cable with new GBIC module, but switch port is NOT working (no blinking).
- Show int status result:
- I tried Port shutdown and no shutdown, but no different.
- Try another GBIC module, still not working.
Do you think my fiber port has faulty? Is there any command line that I can check the port status?
Thank you very much.
08-18-2022 01:29 PM
make sure you are maping Tx to RX and vise versa, if its multimode, you can check the light, if its single mode, just try reversing the fiber cable and see if it works.
08-18-2022 01:31 PM
Hi,
There is no command to test the fiber port. Can you try a different fiber patch cord?
Also, are you using the correct fiber patch with the correct SFP?
If the fiber is single-mode, you need single-mode SFPs.
If the fiber is multimode, you need multimode SFPs.
HTH
08-18-2022 02:05 PM
Hello, Thank you for your response.
Fiber cable is multi mode, LC-LC type(OM4 Duplex multimode, aqua color) and module is also multimode (Cisco GLC-SX-MMD).
I also tried fiber patch cord (1,2 - 2,1 or 1,2 - 1,2), but still does't work.
When I plug device (firewall), firewall port is blinking (uplink is fine).
However, only switch port gives me 'notconnect' interface status..
01-31-2024 01:14 AM
I am facing same problem.
Did you get any solution.
Please share with me.
Thanks.
01-31-2024 01:40 AM
Hello,
the same problem meaning on the same device (3750X/2960X) switches ?
01-31-2024 01:50 AM
Hello, Thank you for your response.
I have Cisco C9300X-12Y switch (SW Version : 17.09.03),
and Sonicwall NSA5600
Firewall and switch are connected by fiber optic cable
multimode fiber
SFP "GLC-SX-MMD" on both side.
Sonicwall port comming up but cisco switch port show down.
I also tried fiber patch cord (1,2 - 2,1 or 1,2 - 1,2), but still does't work.
I gave the command "speed nonegotiation" , but still does't work.
Thanks.
01-31-2024 02:05 AM
Hello,
understood. Can you post the output of 'sh int' of the interface on the 9300 that is connected to the SonicWall ?
01-31-2024 02:47 AM
Please find below
Switch#sh int TwentyFiveGigE1/0/12
TwentyFiveGigE1/0/12 is down, line protocol is down (notconnect)
Hardware is Twenty Five Gigabit Ethernet, address is 9088.5553.2d8c (bia 9088.5553.2d8c)
MTU 1500 bytes, BW 25000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseSX SFP
input flow-control is on, 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: 0/2000/0/0 (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
Output 0 broadcasts (0 multicasts)
0 output errors, 0 collisions, 9 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
Switch#
Switch#
Switch#sh run int TwentyFiveGigE1/0/12
Building configuration...
Current configuration : 80 bytes
!
interface TwentyFiveGigE1/0/12
switchport mode trunk
speed nonegotiate
end
Switch#
Switch#
Switch#sh int TwentyFiveGigE1/0/12 statu
Switch#sh int TwentyFiveGigE1/0/12 status
Port Name Status Vlan Duplex Speed Type
Twe1/0/12 notconnect 1 full 1000 1000BaseSX SFP
Switch#
Switch#
Switch#
Thanks.
01-31-2024 03:11 AM
Hello,
as far as I recall, the SonicWall lets you set either AutoNeg or 1G. On the Cisco, I think you cannot set the speed, so make sure that both sides are set for Autoneg.
08-18-2022 02:56 PM
https://www.youtube.com/watch?v=gORYoiCp-Sg
this video help you,
check command use to check the Fiber health
08-18-2022 03:57 PM
Loop the fibre and see if the LED goes green/amber or not.
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