I'm planning on using some hardware I have laying around to throw together a NAS/Home Server PC this summer. It's a fairly powerful rig, running a 2.9GHz Dual Core, 2GB of DDR3, and on-board HD Graphics. Nothing special, but overkill for this project; that's how I like it. I just want some simple tasks to be performed by this machine, and I'll sure I'll add more as time goes on. The top priority is a NAS. I need a bunch of storage, and I'd like for it to be accessible by both my current computers. I have a whole bunch of questions however, none of which are really related
1.) I'm planning on running software RAID (Through either Linux or BSD), using 2 disks. I kind of have two ideas that I'd like to go with, but I'm just not too sure what to do.
i.) RAID 0. Nice and fast, no redundancy. Would need to back-up to an additional disk.
ii.) RAID 1. Redundancy, but no increase to speed. No need for additional disks.
So looking at these 2 options, I'm not sure which to go with. While I only have a 100-Mbit router at this point in time, I do plan on getting a Gigabit router once this is all up and running. I'd like to shoot for speeds of >100MB/s. I know Gigabit's theoretical limit is 125MB/s, so I think 100 should be achievable. If it's slightly under I'm fine with that, but this is just simply a goal. Anyways, will the RAID-1 configuration give me the speeds I'm looking for, or will I need to go RAID-0 in order to achieve these speeds? I know it's hard to say, and I hate asking such a generic question, but I'm hoping somebody has enough experience that they can give me an estimate.
2.) Do I need separate drive for the OS? From what I've read so far it seems like you can't install an OS on the RAID array if you're using software RAID. I'm fine with this, just curious as to whether or not this is the case.
3.) If you do need an OS drive, what kind of I/O Speeds do you need? Does the Read/Write speeds for the OS significantly, or does it just kind of need to be there? I'd like to be able to just use a modified USB drive, or an IDE/Sata Module or something. Also helps me determine what kind of HD to get if I do need one.
4.) What am I looking at for expandability? If I wanna add another 2 drives down the road when I get some more money to do a RAID-10 or something, will I be able to re-build the RAID, or will I just need to back everything up and restart from scratch? Does using EXT3/4 or ZFS make a difference for this?
5.) Are the rumors about the reliability of the 1.5TB & 2TB HD's true? Should I stick with 1TB drives, or are these larger capacities safe to use?
Thanks in advance to anybody that takes the time to even read this post I'm very new to all this, and am just looking to get things sorted out so I can tell myself I have any clue what I'm getting into
1) I'd get a raid 1. NAS isn't primary storage, it's backup, right? Your network will be a bottleneck, not just because of the bits per second, but the latency compared to a local hard drive, and the overhead of windows smb over a network.
2) Not sure, but why not use raid from the motherboard (if the chipset supports it?)
3) OS read/write is probably only an issue on a NAS for bootup, then very small usage after that. Data drives are much more the issue.
For me, I'd get 2 drives in a mirror, partition off 30-50GB for os & maybe a few apps, then leave the rest for storage. I'd also make an occasional backup to removable media, just to take something offsite.
Thanks for your input. Pertaining to your first answer, I just now realized I left out a bunch of information last night. I'm wanting to use it more as a media-server type of deal; I want to store all my movies, tv series, music, etc on this rig, and have them accessible to all other computers connected to the network. I'd also like to be able to stream to my PS3 to play the videos on my TV.
As for the onboard RAID, I guess I must have gone and confused myself here. I was under the impression that MoBo RAID was "Fake RAID". I should stop posting threads in the middle of the night apparently I'll look into what my motherboard supports.
I'll definitely get some form of removable media once money permits. I have faith that the drives will last that long, and if they don't, it's my own fault.
Alright, rethinking this a bit. I'm trying to simplify this, as I've made things overcomplicated. I have 2 options that I'm considering at this point.
i) 2x 2TB drives in Software-RAID1. This gives me 2TB of space with redundancy.
ii) 2x 2TB drives. I'd just rsync the drive on a daily/weekly basis, or something to that effect. Considering wiring a switch into the power connector for the backup drive, to minimize it's use and maximize it's lifespan. Something to that effect.
I'm just wondering if it's worth setting everything up with RAID1, or if I should just back things up manually.
raid is more of an "uptime" issue - if a drive dies, you have another drive still running, vs. going to backups. So if you can afford a little downtime, I'd go with 1 drive for the data, and 1 for backup (extra bonus for external backup). Not sure if it's worth messing with a power switch - could add more risk of drive failure than just letting it run, but in an external case you can turn it off & detach when not in use.