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Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

Hey guys, I'm having some issues connecting my Netgear GS724Tv4 24port switch to my Unifi 16 XG via Fiber SFP.  I just got the Unifi 16XG and I'm still working out a few bugs.

 

I'm using Finisar SFP to Multimode Fiber modules.  

 

To give you an idea of my knowledge in all this, I managed to somehow use singlemode fiber with these modules and everything connected between my Unifi 24 port switch and the Netgear switch.  

 

So, I purchased some multimode fiber, now that I know the black bar on the modules represents Multimode.  I now know that I have the correct fiber and module connecting to each other.  I know that the modules are compatible with both the Netgear switch and Unifi 24 port switch since I've had those two connected to each other.

 

I also know that the modules work with the Unifi 16XG switch since I have the Unifi 24 port and Unifi 16 XG connected to each other via SFB Multimode Fiber (with a tweak on the Unifi 16XG side.  I had to go from auto negotiate to 1gig mode).  

 

What I'm having issue with is the netgear 24 port switch.  I've gotten the Unifi 16XG to detect that those ports are active in the same fashion I hooked the Unifi 24 port switch up (by decreasing link speed).  The problem is, the Netgear web interface still says the link is down.  On the Unifi 16XG I have lights on for the corresponding ports, but I don't have any blinking.  They are just a solid Green.   The only way I can access the netgear switch is via Rj45.  I've factory reset the switch to see if that was an issue, but it continues to show link down.  

 

I think I've tired everything I can imagine...  I have trouble believing it's hardware related since the modules worked in another config, but with my prior comment about my knowledge of these things, I could be wrong. 

 

Any help would be appreciated.

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

if you got this working with a patch of single mode fiber and the only thing you have done is swap to multi mode I would check to make sure the fiber is good. On a multimode fiber/sfp you can look down the end and see light coming through on one side. Check and make sure you have light coming out of both of your optics on one side then connect your fiber and ensure you see light coming across the fiber. Then finally make sure you fiber isn’t rolled (very common) and the transmitting side from the opposite end is going into the receiving side of the optic on the other end.

 

Typically when you are using a 1gb SFP in a 10gb SFP+ port you will have to manually set the speed/duplex.

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

I’ve verified that the fiber cables work with the 24port UniFi switch.  I’ve also ensures that the speeds on the UniFi 16xg were manually set to 1G.

 

im still at a loss

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

To be more clear.  I had the fiber connections (single mode) working between the netgear 24 port switch and the UniFi 24 port switch.  I never had it working between the netgear and the UniFi 16 xg.  

 

Using multi mode I have the connection working between the UniFi 24 port switch and the UniFi 16xg.

 

what I have not verified is using multi mode with the netgear and UniFi 24 port to verify that still works.

 

What i don’t understand is why the same SFP modules and fiber cables don’t produce the same results when I go from a UniFi 24 port switch to the UniFi 16xg.  Making sure the ports are configured the same for the netgear and UniFi 24 port switches.

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

I was able to verify tonight that when I plug the multimode fiber from the netgear into the unifi 24 port switch all is functional.  Now I just can't figure out why the Unifi 16 XG isn't working....

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

You mentioned you are using Finisar optics earlier, are you using them on both sides? What I am wondering is if those optics will work correctly in the XG or not and if the XG is capable at coming up at 1Gb on the SFP+ ports. I don’t have access to an XG switch right now so I can’t say for sure but i’ve only configured this in 10Gb using the UBNT DAC/Twinax cables to the SFP+ ports on other UBNT switches. I know that when you insert an unsupported optic in other vendor’s switches they will sometimes refuse to come up, might be worth SSH’ing to the XG and looking in the logs under /var/logs/messages to see if it has anything like ‘unsupported transceiver’ in there. Finally if you insert an optic into the XG and set the speed do you see light coming out of it?

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

I can say with certainty that it was the transceivers.  I was using some SFP fiber modules that I had from a SANbox i got from work and apparently these specific finistar SFP modules can do 1-4 Gigabit.  That makes sense that i had to tell the XG to go to 1gigabit and not autnegotiate.  I purchased some ipolex SFP modules on amazon that are made to work with Ubiquiti, and lucky thing it says Netgear as well.  This solved my problem.  The second I put the ports back to autnegotiate the netgear SFP port lit up.

 

I have a few others coming from Unifi to play with as well, but it's good to know that not all SFP are created equal, and I think that's the confusing part of advanced networking.  Gone are the days of simple ethernet plug and play unless you want to pay out the wazoo!

 

Thanks for the help guys.

 

The model modules I got are X0013YJLBR (these are Single mode modules) they run at 1Gigabit.  I also purchased 2 X0013YJEJV modules which run at 10 gigabit, but I haven't been able to test them since I'm  still sorting out the fiber side of my setup.

 

 

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Re: Unifi 16 XG to Netgear GS724Tv4 via SFP fiber

It turns out it was my specific modules.  They just weren't compatible with the unifi switches, and definitely not compatible with the Netgear switch.  I picked up a few from amazon and a few from unifi, and they all work.