im considering getting the nvme duo to build a pi nas but im wondering is there a max cap to the amount of storage it can take. it seems in the listing you can get it with a max of 4tb (2x2Tb drives) but im wondering would it take for example 8 tb in total (2x4Tb)
Neither the OS, nor the physical connection will limit you. But honestly, if you need that much storage, there are far better solutions (even if you don’t need that much storage).
I recently evaluated some of the mini N100+12GB RAM systems. Some of them offer 2xPCIe NVME slots. If you add up everything you have to buy (Pi5, NVME-base/hat, case, power-supply) and so on you will have a cheaper and more robust solution with one of those N100 minis. And since the N100 offers more PCIe lanes, you will also have a faster system.
im not needing a superfast device this is more budget constraints than anything else. iv not seen any conventional nas that comes close to the price most are at least 2 to 4 x the cost of building the pi nas. without drives.
I am talking about budget (the N100 is not superfast compared to the Pi5). I can get a N100 with solid cooling, case, and power-supply for 130€ and lower. And no flimsy FPC-cable for PCIe with shared single lane. Read in this forum about all the problems users have with that. And sit down and add up all the components you need and you will see how this sums up.
The days have passed when the Pi was a budget solution.
There is one single argument for using a Pi for a NAS: it is still a fairly low-power device. The N100 is also very good, but not as good. But with 8TB I would put my emphasis on reliability.