topic RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it? in ExtremeSwitching (EXOS/Switch Engine)

When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Tue, 17 Nov 2015 23:24:00 GMT

hello Guys , I have added new switch type Summit X450-24x DC in my network , when i creating any Vlan after 1 hours loop happen in network , why that happened , Is there commanded or method to shows me where the defect was?

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Thiago_da_Silva — Tue, 17 Nov 2015 23:40:00 GMT

I believe that you should do test without the cables of networks.
If not working.
The loop can be into your network.
You should do update in switch.
If you have problem, please write me.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Tue, 17 Nov 2015 23:46:00 GMT

I appreciate your feedback, but how I can doing test without Cable?

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Jeremy_Gibbs — Tue, 17 Nov 2015 23:53:00 GMT

Assuming you are running stp,

show stpd s0 ports blocked-ports

show stpd s0 ports non-forwarding-reason

show stpd s0 ports detail

These commands might help you solve your problem.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Thiago_da_Silva — Wed, 18 Nov 2015 00:20:00 GMT

Hello,

You should segment the network.
Taking the cables on to one.
You will see if there is one problem in your network.
you have create one instance Spanning tree.

create stpd EX: stpd_S0
config add vlan ports dot1d
config tag
config mode dot1w
enable stpd
enable stpd

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Patrick_Voss — Wed, 18 Nov 2015 00:48:00 GMT

How are you confirming there is a loop in the network? Loops usually present themselves instantly so it is odd it takes an hour.

If you could give us a brief topology that would be helpful as well.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Wed, 18 Nov 2015 03:57:00 GMT

yes you are right, i think got on broadcast in network

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Dorian_Perry — Wed, 18 Nov 2015 03:57:00 GMT

Hi Munir,

Yes, considering the time delay of the issue, this is more likely to be a broadcast storm. If you connect a PC to one of the switches and assign it to the same VLAN experiencing the issue, a Wireshark packet capture should help in tracking down the source of the broadcast traffic.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

SchmuFoo — Wed, 18 Nov 2015 15:27:00 GMT

You can try to nail down the problematic port with..

.. Extreme Loop Recovery Protocol (ELRP)

configure elrp-client one-shot "VLANe-Name" ports all print
https://gtacknowledge.extremenetworks.com/articles/Q_A/Which-commands-can-be-used-to-detect-a-loop

or

.. check the pkts/sec counter for high counters

show ports utilization

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Wed, 18 Nov 2015 15:27:00 GMT

in which switch i would do configure elrp. the switch that has the problem?

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Patrick_Voss — Wed, 18 Nov 2015 15:27:00 GMT

All of them. This will give you the best chance of finding the loop if there is one in the future.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Wed, 18 Nov 2015 15:27:00 GMT

thank you

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Thiago_da_Silva — Wed, 18 Nov 2015 22:09:00 GMT

How is your topology?
If it is a ring, you will need a loop prevention protocol such as EAPS or ERPS Extreme.
The ERPS protocol there is the CFM, that work with switches that are not have ERPS.
Is very nice.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Thiago_da_Silva — Sat, 21 Nov 2015 04:15:00 GMT

What problem friend!
There seems to be a loop topology, can be a loop on the door or a machine with a virus.
Once I shared the problem in such a network.
I had a machine that had a virus.
This virus was flooding the network with broadcast.
I took a one of the machines on the network and saw what was the machine that was causing the issue. It was a machine with full access.
you will have to do the same.
if you want to put EAPS which only works on network ring tell me I mands commands.

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Sat, 21 Nov 2015 21:07:00 GMT

the problem fixed, with new plan in our network i removed one switch and i re-arrange the vlan for each port , But my concerns when adding a new switch i will getting same problem. thank you fro your support

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Wed, 25 Nov 2015 14:37:00 GMT

*Apr 14 02:05:53.689: %ETHCNTR-3-LOOP_BACK_DETECTED: Loop-back detected on Gigab itEthernet0/3.

*Apr 14 02:05:53.689: %PM-4-ERR_DISABLE: loopback error detected on Gi0/3, putti

ng Gi0/3 in err-disable state

*Apr 14 02:05:54.713: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth

ernet0/3, changed state to down

*Apr 14 02:29:05.485: %ETHCNTR-3-LOOP_BACK_DETECTED: Loop-back detected on Gigab

itEthernet0/3.

*Apr 14 02:29:05.485: %PM-4-ERR_DISABLE: loopback error detected on Gi0/3, putti

ng Gi0/3 in err-disable state

*Apr 14 02:29:06.500: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth

ernet0/3, changed state to down

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Wed, 25 Nov 2015 14:37:00 GMT

i got on this massage , what mean and how i can fixing? this massage from Cisco switch ,its linking directly with extreme switch

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

Jeremy_Gibbs — Wed, 25 Nov 2015 14:37:00 GMT

https://supportforums.cisco.com/document/20111/error-ethcntr-3-loopbackdetected-catalyst-switch-runs-cisco-iosr-softwarE

RE: When creating a vlan, I get a loop after 1 hour in network. How can I check it?

MUNIR_ENG — Wed, 25 Nov 2015 14:37:00 GMT

thank you