Hello Leon
This is an interesting endeavor, and a very useful one for today’s market. I am by no means an expert, but I can share with you some of my experience as well as the results of a short research I did on the topic. It seems that there’s no single undisputed player in SAN/storage vendors like there is with Cisco.
Dell EMC is probably the largest, at least by revenue, and one of the largest install bases in the world. NetApp, Pure Storage, HPE and IBM are all strong contenders as well. A note on Synology, although it is a well known name, its primary focus is SMB markets, and I would not characterize it as a “Tier 1”, datacenter grade, or enterprise grade player.
Now concerning certifications, I would probably focus on two: NetApp and Dell.
NetApp has the most mature certification path, which is similar to the CCNA → CCNP → CCIE path of Cisco certs. From a certification standpoint, I think this is the best designed and has the widest recognition. This is probably your best bit if you want to be as vendor-neutral as possible.
Dell, because of its installed base is also quite good, and its certifications are typically product-specific.
I suggest you research those two primarily, and then take a look at HPE, and Pure Storage cert options.
Finally, if you want to remain completely vendor-neutral, take a look at the Storage Networking Industry Association (SNIA) with vendor-neutral certifications (SCSP, SCSE) covering protocols, RAID, availability, and data protection. They are excellent for foundational knowledge, but employers typically search resumes for “NetApp” or “Dell EMC” rather than “SNIA.”
I hope this is a good start for you, and it gets you going on your own research to find the best optoin for you. Keep us posted on your progress, it would be interesting to see your results!
I hope this has been helpful!
Laz