Was buying FibreChannel a good deal?
1) FC doesn’t work for hyper-converged, adapter firmware supports initiator or target mode, not both. As such, you could not host FC storage in the same chassis as it is consumed.
2) Scale-out storage which is far more capable than SAN requires multicast to replicate requests across all sharded nodes. FC (even with MPIO) does not support this. As such, FC bandwidth is always limited to a single storage node. With MPIO, it is possible to run two separate SANs for improved performance but the return on investment is very low.
3) FC carries SCSI (or in some cases NVMe) over a fibre protocol. These are block protocols which require a huge amount of processing on multiple nodes to perform block address translations and make use of long latency operations. In addition, by centralizing block storage, controllers have to perform massive hashing and lookups Tor possibly hundreds of other nodes. This is a huge bottle neck which even ASICs can’t cope with. Give massive limitation in the underlying architecture of FC SANs, distribution of deduplication tasks is not possible.
4) FC (even using Cisco’s MDS series) has severe distance limitations. This is controlled by the credit system which is tied to the size of the receiving buffers. Additional distance add additional latency which requires addition buffers to avoid bottle necks. 32Gb/s over 30km of fibre probably requires 512MB of fast cache to avoid too many bottle necks. At 50km, the link is probably mostly unused. Using FCoIP can reduce the problem slightly, but iSCSI would have been better and SMB or NFS would have been infinitely better.
I can go on, but to be fair, unless you have incompetent storage admins, FC has to look like a dog with fleas by now. We use it mostly because network engineers are horrible at supporting SCSI storage protocols. If we dump SCSI and NVMe as a long range protocol, the problems don’t exist.
I would however say that FC will last as long as storage admins last. Since they are basically irrelevant in a modern data center, there is no fear that people will stop using FC. After all, you can still find disk packs in some banks.