topic Re: Stacking Ports Flapping X460-G2 in ExtremeSwitching (EXOS/Switch Engine)

Stacking Ports Flapping X460-G2

Christopher_Tay — Wed, 20 Mar 2019 22:22:29 GMT

We have 9 X460-G2 stacks running version 22.5.1.7 and we have noticed that the stacking ports are flapping on a regular basis.
The link goes down on Stacking ports 1:2 and 2:1 then comes back up.
Has anyone else experienced this problem? What was the resolution?

Thank you

Re: Stacking Ports Flapping X460-G2

CFaber — Wed, 20 Mar 2019 23:05:38 GMT

Silly Question: Did you try replacing the cable?
The only time I had this problem, the cable had a serious issue ?

Re: Stacking Ports Flapping X460-G2

Christopher_Tay — Wed, 20 Mar 2019 23:11:48 GMT

We have re-seated the cables and rebooted the switches but not changed them.
As it is happening to all of our stacks I find it difficult to believe it is the cables unless I got a really bad batch.

Thank you,

Re: Stacking Ports Flapping X460-G2

CFaber — Wed, 20 Mar 2019 23:20:00 GMT

Interesting behaviour.
Are you using 22.5.1.7 or 22.5.1.7-patch1-2 or 22.5.1.7-patch1-3?
Are you using extreme-stacking-cables or third party-stacking-cables?

Re: Stacking Ports Flapping X460-G2

Sarah_Seidl — Wed, 20 Mar 2019 23:34:14 GMT

We had some issues with slots randomly rebooting and TAC recommended that we
configure stack-ports debounce time 150.
We just did that recently and are currently monitoring. Difference with us we have 460-48p Generation 1s, running a 16 code (with v.80 stacking - extreme branded)
then you can show stack-ports debounce to confirm the time (ms) took place.

Re: Stacking Ports Flapping X460-G2

AdrianO — Fri, 22 Mar 2019 19:55:13 GMT

We had the same problem, changing debounce time on stacking ports fixed it. I wonder what are the implications of this and if there is none or if is necesary why its not the default value....

Re: Stacking Ports Flapping X460-G2

Chris_H — Mon, 25 Mar 2019 16:00:13 GMT

Hello,

The 10Gb/stacking ports flapping in 22.5 on the x460G2 is a known issue that will be fixed under xos0073360.

In the meantime i suggest, like already mentioned before, to configure 150ms debounce timers on the stacking-ports as explained in the following article: https://gtacknowledge.extremenetworks.com/articles/Solution/Link-flaps-continuously-on-X460-G2

The implications of setting this 150ms debounce timer are that in case of a valid link down event of these ports, the switch will wait 150ms before it declares the link to really be down, so this could cause additional latency/delay in case of a real failover.

best regards,
Chris

Re: Stacking Ports Flapping X460-G2

AdrianO — Mon, 25 Mar 2019 16:29:04 GMT

Thanks @ChrisH