So i-am playing around with freenas a bit and i'm about to buy 4 500GB identical disks (cheap).
But i want this server to store my important documents and vacation pictures and such. So how should i set up the drives?
I could do 2x2 drives so 1TB of storage cloned. Or i could do 1x2 drives 500GB storage for important stuff cloned(raid1) and 2x1 drive 1TB storage for torrents and general storage (raid0) wich i think might be a better choice?
I don't know how raidz works so what would be the recomended setup for me?
I would do a raidz equivalent of raid 5 so you have 1.5tb storage and the forth disk for redundancy. I've heard that freenas likes odd numbered drives though so I'm not sure if that's important or not.
It uses a data parity, meaning if any one of your drives fails, the other three will retain your data, and you can replace the 4th drive, rebuild the RAIDZ, and you are back to protected status. If two drives fail at the same time, you lose your data.
Yeah, raidz is what i mean. raidz has one disk redundancy, raidz2 has two etc.
The data isn't copied to the forth disk, instead the parity data (essentially the sum of the other disks) is stored there. So if disk1 + disk2 + disk3 = parity then parity - disk1 + disk2 = disk3 (this is a pretty basic explanation but that's essentially how it works.) So if one disk fails you can recover the data on it, but if two disks fail you lose everything.
Totally awesome! and that would mean that it does not matter wich drive fails right? as long as it's 1 drive at the time.
The biggest reason why i want this is because i buy these disks used. but hey 40 bucks for 4x 500GB hdd's aint bad for a student right :P
(Hitachi HUA721050KLA330 x4)
The server has a G1820 and 8GB of ram but i think that's a bit overkill? might change it to 4GB? also i-am planning on putting a UPS inside of the pc case.
If you want to use freenas the more RAM the better. If you don't want to have lots of ram then something like rockstor which runs btrfs might be a better option.
i think to myself (what a wonderful...) that 8GB might be abit overkill for 2TB when i could get away with 3GB but just put in 4GB. Those 2x4GB sticks can be used in another system ;) but i'll see maybe i'll use some very fancy options that saturate the 8GB's of ram. After all, ram not used is ram wasted
While possible nobody advises this long term... replace the drive as soon as possible because it will take some time to rewrite the disk and if another drive dies before the disk is finished rewriting you'll lose some data
I've read (and @wendell also mentioned it in his freenas video) that Freenas works better with 2^n+1 drives, but I have not found any decent explanation about it yet. Would somebody please explain what's the drawback of using like in this example 4 drives instead of 3? Has it something to do with better space usage?