Hello all,
I am adding a 3rd spine ("Spine 3") to our ACI fabric and we are making use of some fiber patch panels that we have in the datacenter. The fiber patch panel has standard fiber "cassettes" which take an MTP fiber connection on the back of the cassette (an MTP fiber cable has 12 fiber strands), and the front of the cassette has 12 LC ports (so the 12 MTP fiber strands break out into the 12 LC ports on the front of the cassette. And for plugging in LC fiber cables, since each LC fiber cable has 2 "ports" (send and receive), you could hook up 6 LC fiber cables to the front of the cassette). The fiber cassette looks something like this: Customized MPO MTP® to LC/SC Single-Mode Fiber Optic Plug-N-Play Cassette - FS
So, to make use of these fiber cassettes in the fiber patch panel, what we have done is run an MTP cable from e1/1 on Spine 3 to the back of the fiber patch panel cassette. Then on the front of the fiber cassette, we have run 2 LC cables to 2 different Leafs. So it looks something like this:
LC
+-=-=-=-=-=-+ e1/1 (MTP) +-=-=-=-=-=-=-=-=-=+ -------- | Leaf 1 |
| Spine 3 | ============= | Fiber Cassette |
+-=-=-=-=-=-+ +-=-=-=-=-=-=-=-=-=+ -------- | Leaf 2 |
LC
The SFP on the Spine side is a 40-gig QSFP (QSFP-40G-SR4 since we're using an MTP fiber cable) and the QSFP on the Leaf side will be 40-gig as well (a standard LC 40-gig QSFP).
My concern is that we have Leaf 1 and Leaf 2 both ultimately connecting to Spine 3 via a single spine port (e1/1). And this concern is extended because we have 20+ Leafs that will be similar to this configuration, i.e. each "pair" of Leafs will connect back to a respective single Spine port on Spine 3 (Leaf1/2 to e1/1, Leaf 3/4 to e1/2, etc.)
Is this a supported cabling configuration? Should I be concerned? Our other 2 Spines (Spine 1 and Spine 2) both connect to all the Leafs with straight-through LC-LC fiber cables at 40-gig, so this MTP-to-LC configuration with Spine 3 is a first for me.
0xD2A6762E
