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problems with SFPs

Posted: Thu Jun 15, 2017 12:16 pm
by mgthump
I'm struggling to get SFPs working in the sw12-250AC switches. if i reboot the switch with our SFP in them, it may or not not take and link. if the SFP is removed and inserted they won't come back until i reboot.

both switches are on 1.4.6, board F.

I've got a old sw-12-250B running 1.4.6 that is taking these SFPs without a problem and the rest of my switches here don't seem to mind them.

I've already played music SFPs and all of the SFPs i have are fine in the planet, juniper and older sw-12-250b, but they won't reliably work in the board F 12-250s i've got in service. these are about 2 months old.


I've tried planet MM 2km SFPs and fiber store SFPs and no go.


any ideas on this?

Re: problems with SFPs

Posted: Thu Jun 15, 2017 12:31 pm
by sirhc
Well please upgrade to to v1.4.8rc6 or at least v1.4.7 but remember bugs found in v1.4.7 are fixed in v1.4.8rcX

With that said I so have come across SFP modules (which I have talked about in posts) that I found would stop working on a warm reboot such as a firmware upgrade or UI/CLI directed reboot that would require me to pull out the SFP and reinsert it.

Weird thing is I would have the same make and model SFP that works flawlessly. I would swap out the SFP module with another one, sometime same make and model sometimes another brad and problem goes away.

Also note that some SFP modules work best with SFP port Speed set to Auto and other work better set to 1G. Most time you need to make sure the other side of the link is also set the same either Auto or 1G.

With that being said I would tend to point my finger at the SFP module being the issue but you may disagree?
I do suggest when using an SFP module to fully put it through the paces before putting in service.

Insert SFP and get a link.
Do a warm reboot in the UI/CLI (same as a firmware upgrade reboot) make sure the link comes back up.
Do a cold boot (power cycle) and make sure the link come back up.
If it fails try setting port speed to both Auto and then 1G and see which works better with that module.
If it still fails try another SFP module, maybe same brand and then another brand and test again.

Re: problems with SFPs

Posted: Mon Jul 03, 2017 5:05 am
by jowang
You should know which optical transceivers can be used in WISP switches, read the previous link posted in Netonix forum or directly read the articles below http://www.fiber-optic-transceiver-modu ... witch.html

Re: problems with SFPs

Posted: Mon Jul 03, 2017 9:08 am
by sirhc
Our switches "should" work with any Cisco compatible SFP module but since not all manufacturers follow the spec the only way to test each module would be to buy every module on the market and test them.

Re: problems with SFPs

Posted: Sat Jan 11, 2020 12:39 pm
by cable guy
My experience with SFP not working was resolved when I hard coded the SFP port to 1000

also means I can't plug a 10/100 device into after that

Re: problems with SFPs

Posted: Mon Jan 20, 2020 9:09 am
by mike99
cable guy, Netonix on both side ? The only time I had to use static rate and duplex is when the remote device didn't support auto.