XS716T to XS712T with SFP+ and fibre

Salut coxbuell​ 

Nothing specific to activate.

Fiber isn't that simple and straightforward like copper Ethernet, but in most aspects very similar.

1. Using the correct spec SFP+ modules for the finer type? There are Multimode Fiber (MMF) and Single Mode Fiber (SMF) modules -and- fibers? There is a big difference in the core diameter of the fiber (9 um vs. 50...100 um), and the optics on the module itself is therefore very different.
2. Done a loopback test with one fiber (both ends of the same fiber into the SFP+ module to proof the module (and the fiber) is basically operational? The respective LED will come up on the switch.
3. Not all vendors allow the usage of random SFP+ modules, most restrict the usage of modules carrying the same exact maker and designation flashed. To my knowledge, Netgear doesn't require that on newer switch models like the XS712T and the XS716T. However, NEêtgear does only support the original Netgear modules as specified with each switch model.
4. Which exact switch models (XS712T or XS716T, and XS716T or XS716Tv2)?
5. Which SFP+ modules (brand, and exact type) do you have in place?
6. Have not deployed by accident classic 1 Gb SFP Transceiver 1000BASE-LX modules?
7. Last but not least, which firmware versions are in place on your two switches?

These are for example the lists of supported module types and variants on the XS712T and the XS716T:

Source: https://www.downloads.netgear.com/files/GDC/datasheet/en/XS712T-XS728T.pdf

Source: https://www.downloads.netgear.com/files/GDC/XS708T/XS708T_XS712Tv2_XS716T_XS728T_XS748T_DS.pdf