I've got several mac minis (Intel) - each is dedicated to a single client, and runs FileMaker server and Apache (and sometimes a few other minor services). I've been happy with this setup, but am planning a move to the M1s soon.
There are benefits to having separate hardware servers, but also risks as well, and I'm wondering if now might be the time to virtualize?
What if instead of running N separate M1 mac minis, I ran a single M1 (maxxed out with RAM/SSD) which ran several VMs inside it. I would probably run one VM per client, since I like to keep them very isolated from each other. I would run VMs of macOS (since that's what I know) but I suppose I could run Linux VMs if that made more sense.
Each client's workload is generally a monthly process, which tends to not overlap much in time (e.g. client 1's busy days are the 1st to 5th of the month, client 2's busy days are 10th to 15th, etc.)
(iii) to install, use and run up to two (2) additional copies or instances of the Apple Software within virtual operating system environments on each Mac Computer you own or control that is already running the Apple Software, for purposes of: (a) software development; (b) testing during software development; (c) using macOS Server; or (d) personal, non-commercial use.
Compared to traditional server hardware, the mini has none of the redundancies that provide for high reliability server services. That being said, even redundant systems can fail, and everything on one box, increases the "single-point-of-failure" probability, although redundancies mitigate that considerably.
One per Mac mini, would provide single-point-of-failure for one client FMS instance (the max FM license allows). You can mitigate the SPoF risk by using something like MirrorSync to mirror the entire server to a second mini.
Note that current M1s max out at 16gb (hopefully to change maybe this spring ) but the price/performance benchmarks make it a highly attractive option as a server box, even with the additional cost of HA/FT using parallel hardware and a MirrorSync type approach.
I just looked up Apple's Software License Agreement for Mac OS. It is as @xochi quoted. Users are limited to two copies of Mac OS X within virtual operating system environments on each Apple-branded computer… and only when used for specific purposes.
The way I interpret this section, I am limited to two virtual machines with Mac OS X on a Mac, and I must have Mac OS Server installed in each VM if I am to offer FileMaker server services from these VMs for any purpose other than software development purposes or for personal, non-commercial uses.
@Malcolm I believe the limitation is only for hosting macOS VMs ("child VMs") within a macOS Host VM. In your case, you could host an infninite number of linux VMs within a macOS M1 host.
This brings up an interesting point: though I'm most familiar with macOS, if hosting FileMaker server on a Linux VM (with Apache) is relatively easy, that may be a valid solution I could use.
However, this would be a problem as @Otmar points out. ClarisPKB doesn't seem to specify if it's x86_64 or ARM for Linux, but it seems logical they would mention if they had a Linux ARM version already...