What would be the best RAID solution for a backup NAS and Home Media Server?
My best guess would be to use RAID 0 for the home media server for speed while using RAID 1 for the NAS that will be used for backups, as well as being able to access non-media files from multiple computers. I'd likely be using a pair of 4TB in RAID 0 for the server or 4 3TBs in a spanned volume. And the NAS would be 4 or 6 4TB in RAID 1 in another spanned volume.
Edit: I fear my question was misunderstood. I mean that for the home media server, I would have 2 disks running in RAID 0 for the performance increase, I would be storing movies, music, game installs. i understand that this has no mirroring. For the NAS I would have 4 or 6 drives running in RAID 1. The NAS would be a backup and universal storage space for all of my media and files that I don't need on my media server, tax documents, work/school files, and the like. The NAS would backup from my gaming pc and media server and would be accessible from my laptop and others on my network.
RAID is something new to me, so I only know what I've read, but even then it's rather hazy. I've been lucky so far, and I've had no issues with lost data, but as I build my music and movie libraries, I don't want to get screwed with shortsightedness.
The safest way is to install it in a non-RAID array, giving you separate drives for backing up data. Remember, in a RAID array (striping), when a drive fails, all drives fail.
I use internal drives on my PC for backing up data on the other 3 PC's (and my PC) - all in non-RAID. The advantages of RAID 0 are speed increase and size increase of a single "drive". I utilize RAID at work, because if a drive fails, I have to keep going, can't afford any down-time. At home, I do not utilize RAID. The drives at work are all RAID 5 (mirror/stripe), and theoretically, in a single drive failure, it keeps going, I simply replace the bad drive.
At home, I can afford to be down 2-3 hours while I put a new drive in and copy the data.
Do not use RAID 0 for data arrays, a single drive failure and you lose all data with no chance for retrieval. For a home media server, RAID 5 is acceptable, but if you have enough drives RAID 6 may be reasonable. At all times remember that RAID is only for fault tolerance, you must still have adequate backup if the array fails and cannot be retrieved. I currently use an 8 drive (3TB) RAID 6 NAS box for my home media server and it works very well.
If you want to get a little deeper into the possibilities, a NAS running FreeNAS with ZFS raidz is a very resilient approach. It does not require a RAID card, but instead a low priced host bus adapter, like an IBM M1015 which is a cheaper way to get what is an LSI adapter.
I don't think my question understood at first, so I edited my original post. What I'd like to have is a media server that would run in RAID 0 for performance or as JBoD if RAID 0 would be unnecessary. For the NAS I'd run in RAID 1 while backing up my media server and my gaming pc, while also acting as a house-wide storage point.
My opinion is that raid0 is unneeded in a NAS. A single modern HDD can saturate the network, a raid0 will just sit there spinning and waiting to send the next "piece" half the time. Depending on the media server OS, go with splitting up your frequently used file types across the drives. For example. My wife primarily watches her recorded shows/soaps so they go on drive1, my scifi/action stuff goes onto drive 2 so that 1 drive is never trying to feed both of us which it could easily, I just prefer it like that. The next heaviest users would be my young grandkids and their cartoons. That stuff goes onto drive2 with my stuff since I would never be watching my shows if they are here.
ps - what backs up the NAS? Raid is not a backup, Raid1 included. Please make sure your important files are stored in more than 1 device.
The NAS would be the backup. The media server would be the method of broadcasting music/movies, while the NAS is there as a backup. Or I may be misunderstanding the use of NAS as a backup, instead of a different method as a back up system.
Or you can use ZFS RAIDZ
Which needs 1GB per TB storage and a decent CPU - I'm currently exploring/learning about it
With FreeNAS and Openfiler you can use snap-shot - another way of back up
With WHS you can add UMD to stream your media to your smart phones, tablet devices, your your TV if it's support DNLA (Digital Living Network Alliance), or UPnP (Universal Plug and Play)