06-10-2013 08:29 AM - edited 03-07-2019 01:48 PM
Hi,
I have a problem between two switches with etherchannel configured:
Model number : WS-C2960S-24TS-L
System image file is "flash:/c2960s-universalk9-mz.122-58.SE2/c2960s-universalk9-mz.122-58.SE2.bin"
Gi1/0/23 ETH-CH_1_SW-EDGE01 err-disabled trunk auto auto 10/100/1000BaseTX
Gi1/0/24 ETH-CH_2_SW-EDGE01 connected trunk a-full a-1000 10/100/1000BaseTX
Po1 Trunk_SW-EDGE01 connected trunk a-full a-1000
Gi1/0/23 ETH-CH_1_SW-EDGE02 notconnect trunk auto auto 10/100/1000BaseTX
Gi1/0/24 ETH-CH_2_SW-EDGE02 connected trunk a-full a-1000 10/100/1000BaseTX
Po1 Trunk_SW-EDGE02 connected trunk a-full a-1000
sw-edge02#sh int status err-disabled
Port Name Status Reason Err-disabled Vlans
Gi1/0/23 ETH-CH_1_SW-EDGE-0 err-disabled udld
interface Port-channel1
description Trunk_SW-EDGE01
switchport trunk native vlan 999
switchport trunk allowed vlan 1-299,301-4094
switchport mode trunk
switchport nonegotiate
no keepalive
spanning-tree link-type point-to-point
spanning-tree vlan 1-4094 port-priority 0
end
interface GigabitEthernet1/0/23
description ETH-CH_1_SW-EDGE-01
switchport trunk native vlan 999
switchport trunk allowed vlan 1-299,301-4094
switchport mode trunk
switchport nonegotiate
spanning-tree vlan 1-4094 port-priority 0
channel-group 1 mode on
end
interface GigabitEthernet1/0/24
description ETH-CH_2_SW-EDGE-01
switchport trunk native vlan 999
switchport trunk allowed vlan 1-299,301-4094
switchport mode trunk
switchport nonegotiate
udld port disable
spanning-tree vlan 1-4094 port-priority 0
channel-group 1 mode on
end
interface Port-channel1
description Trunk_SW-EDGE02
switchport trunk native vlan 999
switchport trunk allowed vlan 1-299,301-4094
switchport mode trunk
switchport nonegotiate
no keepalive
spanning-tree link-type point-to-point
spanning-tree vlan 1-4094 port-priority 0
end
interface GigabitEthernet1/0/23
description ETH-CH_1_SW-EDGE02
switchport trunk native vlan 999
switchport trunk allowed vlan 1-299,301-4094
switchport mode trunk
switchport nonegotiate
spanning-tree vlan 1-4094 port-priority 0
channel-group 1 mode on
end
interface GigabitEthernet1/0/24
description ETH-CH_2_SW-EDGE02
switchport trunk native vlan 999
switchport trunk allowed vlan 1-299,301-4094
switchport mode trunk
switchport nonegotiate
spanning-tree vlan 1-4094 port-priority 0
channel-group 1 mode on
end
I allready change the wire without success, and allreday restart sw-edge02.
With "udld port disable" the link is working correctly.
Do you have an idea ? (I allready read this thread https://supportforums.cisco.com/message/3787690#3787690).
Best regards.
PD:
I have two anothers switchs working with SFP Cable:
Gi0/25 ETH-CH_1_SW-CORE02 connected trunk a-full a-1000 1000BaseCX SFP Cable
Gi0/27 ETH-CH_2_SW-CORE02 connected trunk a-full a-1000 1000BaseCX SFP Cable
Po1 Trunk_SW-CORE02 connected trunk a-full a-1000
Model number : WS-C3560G-24TS-S
System image file is "flash:c3560-ipbase-mz.122-50.SE1/c3560-ipbase-mz.122-50.SE1.bin"
Solved! Go to Solution.
06-11-2013 01:54 AM
UDLD in copper, works marvelously -- when it works. But when it doesn't, the port goes into err-disable more than a fibre optic port. Hence, the main reason why UDLD for copper lines don't work.
If you and everyone else is fine, then go-ahead. I'm just speaking based from my experience.
06-10-2013 08:38 AM
take udld err disable out of the configs. its for fiber only.
06-10-2013 10:56 PM
Vmiller,
Tough UDLD is designed for fiber , but it also works fine with copper.
It detects the ports failure on errdisable it. (I.e Mean to say one side is up and other side is down) the UDLD detects on copper as well.
HTH
Regards
Inayath
06-10-2013 11:44 PM
Hi Inayath,
While I agree that UDLD is supported for copper and fibre, I have seen the side-effects of configuring UDLD on copper ports several times that I've learned to avoid it like a plague.
06-10-2013 05:00 PM
Never, under any circumstances, enable UDLD on a copper link.
What you are seeing is the very reason why.
06-11-2013 12:56 AM
Leo.... PM.
06-11-2013 01:08 AM
Hi Inayath,
PM received. Replied.
06-11-2013 01:47 AM
Hi,
Thanks you all for the answer.
I used to suffer a problem in a switch port years ago, the switch was only sent packet without receive any packet. (was not a wired problem). At this time we only choose to not use this port anymore.
In my mind the udld was the solution for this problem.
I read what UDLD was not necessary in copper wire because negociation already do the job, but for the etherchannel I use "switchport nonegotiate", and I would like be able to detect a cable problem.
For etherchannel do you use "switchport nonegotiate" ?
Do you really think desactivate the udld is the only solution ? (Someone know why is not working as excepted?).
Thought this config has working some time at the beginning, (before the first reboot).
Best regards
06-11-2013 01:54 AM
UDLD in copper, works marvelously -- when it works. But when it doesn't, the port goes into err-disable more than a fibre optic port. Hence, the main reason why UDLD for copper lines don't work.
If you and everyone else is fine, then go-ahead. I'm just speaking based from my experience.
07-02-2013 01:46 AM
Thanks for you answer.
Not really like it, but if it's not working, not working, anyone already open a ticket to cisco about this ?
07-02-2013 01:56 AM
Vincent,
ere are some keep things to remembers
-UDLD is disabled globally and enabled in readiness on fiber ports by default.
-Because UDLD is an infrastructure protocol that is necessary between switches only, UDLD
is disabled by default on copper ports. Copper ports tend to be used for host access.
-You can enable UDLD globally for all fiber ports or on a port-by-port basis. A port
configuration overrides the global configuration parameter.
Ref UDLD enabling on the Copper: http://www.cisco.com/en/US/partner/docs/switches/lan/catalyst6500/ios/12.2SXF/native/configuration/guide/udld.html
Please go through the link above as it will clear the doubt.
I hope this clears up the confusion
Regards
Inayath
07-02-2013 03:22 AM
anyone already open a ticket to cisco about this
You mean report what you are seeing as a bug? I don't think so. UDLD is working, hence your ports went into error-disable.
Could you shed some light as to why you want to enable UDLD on you copper link?
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