I have no experience with servers. The server network I want to setup is going to have a server that will be used for VPN access, a server for number crunching and data mining and processing map data, a storage server for storing data if the project ever goes full scale. I am okay with SSDs if any that are included in the server as long as they are removable.
Edit: A cheap server for VPN as it will be used for connecting people associated with the project to the server network as of now.
go for Arm 
Are they expensive? As in expensive with respect to INR.
As you talk about datamining and processing map data … ARM servers have are really good on this.
more scores a lot more cores…
But i mean depending an skills and biudged… you can build yourself too:
Professional grade ARM servers are not cheap for sure… but energy efficiency counts in that matter too
When I was building out my home lab I was looking at old dell power edge and HP proliant. You can get some insane value in used hardware as most businesses have long since made back their investment on outgoing hardware and sell it for pennies.
I generally look to old Dell/HP server and Workstation hardware. In example iuse to host Minecraft and some other game servers on an old HP Z400 and with about 6 VMs for different servers it hardly broke a sweat. ATM I don’t have a lab after getting rid of a lot before I moved cross country (didn’t want to haul it all) but I wouldn’t hesitate to do it again.
I would argue against this
The power savings for arm is a bit exaggerated in some cases. If your workload is good for arm and you’re doing very large scale deployments where the difference of 250w vs 280w (ampere max vs epyc 7773X) matters to some degree then maybe.
Thing with small scale deployment is ARM really doesn’t offer substantial benefits until you get into the very small/portable and you return to the same question of what the workload is. I.E Intel Atom will generally trash most similar price arm boxes for firewalls with traffic shaping,VPN,etc in my experience. In the case of small business or home lab the biggest concern is upfront cost and time to get roi. In small scale deployment consider maintenance burden (arm will be slightly higher), price, and what gets you the optimal performance within your budget.
It was mainly came to mind to say arm because it is a hype about arm servers currently …
I am in no way an expert on professional server hardware at all!!
There’s no harm in it, its just arm is a bit less established in the space. They’re fun to work with but some people think they’re universally a better choice and this is very workload and cost dependent.
What rack size and depth would you recommend I go for?
This depends on what the server is doing. VPN a 2U is fine, you’ll have more options with full depth. For Data Processing/Storage you’ll look at 4U or more and AFAIK half depth isn’t a thing for 4U.
Unless you mean the actual rack?
I mean the actual rack.
That’s gonna depend on what hardware you get, how much of it, and how much room for expansion you want.
I really can’t answer that for sure, just don’t buy a network rack/cabinet if you want to actually have room
If you want something reliable and performant Synology delivers great NAS.
I am still using a decade old synology 1010+ - their offer some great rack servers.
Synology rack units are completely underpowered for the use case that the OP describes.
Yes - for the datamining thing - you are correct.
Synology NAS uses DSM - the most intuitive control panel I have seen on a NAS - I have not seen all I admit
It is extremely difficult to make recommendations because each and every usecase is different.
Hardware evolves quickly and prices changes rapidly.
And should anyone follow such recommandation and it turns out bad then who’s going to be blamed?
QNap
Supermicro
Even as a NAS, Synology completely falls apart at scale. Also, their rack units are priced very poorly.
I use Synology at home and like them as a simple NAS for a small workgroup. However, they have no place in an enterprise environment or an environment where flexibility is important.
You probably have a personal experience to back the view - and that’s fine.
There has been no mention of budget or pricerange so one suggestion may be as good as the other.
After all it is the OP which ultimately makes a decision - and I sincerely hope it is not based on random comments to an impossible question.
Setting up 3 units using Supermicro is going to be insanely expensive.
I wouldn’t call them perfomant, and on some models reliability is in question, they’re definitely friendly to setup though.
Its not necessarily impossible, but also why assume to setup with expensive gear? You don’t need to buy new and there is so much good decommissioned hardware on the market that’s not even very old. Unless you’re doing a deployment that’s professional or for a business that can afford new going used market is amazing value. There is a middle ground between budget and expensive lol
