Windows Server – How to Create One Big Continuous Space from 4 Disks

1) This is kind of true. RAID doesn't maintain file systems. It only maintains the way bits get written to the drives. The file system is further up the chain. But you're mostly correct in that if the controller itself died, you'd need a similar (but not necessarily identical) controller to rebuild the array.

2) Typically its just another HDD, of greater than or equal capacity, but I have seen instances where the controller was more picky. If you're running RAID1 on a 3-5 year old array and a disk dies, you are going to want to replace both disks anyway, simply because the odds of the second older disk failing are much much greater.

3) Get a NAS device. A ReadyNAS, a Drobo, something. Not for nothing, but if you are just getting into it and you need to ask these types of questions, you're better off sticking with something that's going to do the heavy lifting for you. Keep your focus on your work, not on the technology, leave that to the nerds like me and others.

4) See above, I have deployed ReadyNASes and I know many people who have and love Drobos. There are other options as well, I wouldn't be afraid of anything from QNap, Thecus, Buffalo, Synology, Promise, Lacie, or even Cisco/Linksys, Western Digital, or Seagate. They all have their merits and weaknesses, but all would most likely do the job you're looking to accomplish.

5) There are plenty. You just have to look around. Newegg, as much as I hate shilling for them, has a ridiculous selection, it can take a while to sort through.

Pick your capacity, pick how much growth you might need, and pick what interface you want, then start looking around. I'm a fan of ReadyNAS and Thecus over most others, but do some research and pick the one that's right for you. Its your data, do you really want to trust it to the opinions of some random nerds (or trolls) on the internet? :)

The only reason you would need to use that ratio of RAM to storage space, would be if you decided to use data deduplication. It does not say that the 1 GB to 1 TB ratio is a requirement.

According to a wiki:

Effective use of deduplication may require large RAM capacity; recommendations range between 1 and 5 GB of RAM for every TB of storage. Insufficient physical memory or lack of ZFS cache can result in virtual memory thrashing when using deduplication, which can either lower performance or result in complete memory starvation. Solid-state drives (SSDs) can be used to cache deduplication tables, thereby speeding up deduplication performance.

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