FYI, i dug up an old post from another board that i made when i built this server. Its a bit dated, esp the cost aspect
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the best backup is bittorrent, having 100's of people who can zip it to you overnight.
For a personal collection, the following things need to be kept in mind:
-redundance is required in all cases
-any media will potentially fail
so for true backup, you have the following options:
1. DVD x 2.
cost per GB: 7-8 cents. (Good TY 30 cent bulk media from supermediastore or meritline)
advantages: cheap
disadvantages: very time-intensive, collection gets 'fragmented very quickly'. most people are too lazy to order the good discs online, and buy the crap in the store, 95% of which is less reliable and costs twice as much, at best buy, and they end up using cheap disks, compromising their data
2.Hard Drive x 2.
cost per GB: $1.00 external, 70-80 cents internal)
advantages: quick access, easy to organize collections. best for medium collections (500 GB - 2 TB)
disadvantage: requires manual action to backup, easy to get confused when synching or backing up. Externals are slightly more prone to data loss due to corruption of file tables by USB/firewire connectivity issues.
3. RAID(0) in your PC
cost/gb: 75 cents (2-4 drives+$25 raid card if not onboard
advantages: cheap and easy. best solution for collections under 2 TB. limited to 4 drives, so you dont require dedicated pc or power supply. set up once and forget about it.
disadvantages: little bit of tech required. doesnt use drive space as efficiently as raid 5. limited to 4 drives generally
More on RAID 0
RAID 0 simply simultaneously writes the same data to two different drives, but they are kept in synch in real time, and the user sees only one fileset. so using 500 gb drives:
2 drives : 500 GB of capacity
4 drives: 1000 GB of capacity
4. Serial-ata RAID5 array in a dedicated machine:
cost per gb: 55-85 cents
advantages: can scale arrays from 1-4 TB, and add capacity as needed. parity makes the use of drives very efficient.
best cost/gb over 2TB. set up once and forget about it.
disadvantages: high initial cost. best used with dedicated PC. requires some skills with computers to assemble one
More on RAID arrays:
A RAID5 array uses multiple drives and looks at it as one large drive, so to the user it really is one large drive, which makes managing large collections (over a TB) easier.
The array backs up data redundantly in real-time, thus there is only one fileset to manage, which eliminates a lot of work.
The RAID array uses parity (a different discussion) to back up all data redundantly while using less than twice the space
Array capacity is the number of hard drives minus one * drive size, so for 500 gb drives:
# of drives / capacity
2 / 500 GB
3 / 1000
4 / 1500
5 / 2000
6 / 2500
7 / 3000
8 / 3500
so you use 7/8's of your total drive capacity when its maxed out at 8 drives, or 3/4 of the drive capacity at 4 drives (67 cents/GB The card is $200. If youre going to put 8 drives in a computer, you really need to start with new power supply and good cooling.
I put one together recently, from scratch as a dedicated torrent machine
case $100
mobo + processor $150
good power supply $100
2 x512 MB memory $100
250 GB system/active torrent drive $80
4 x 400 WD RAID-duty drives, $180 each
4 x nice oem (liteon/nec/benq) dvdr's $35 each
I built mine on a 400 gb platform, the 500's are the same price now. Always go with the second best drive size, it generally gives you the best price/performance/expandability, so today, on a 500 gb platform, you would have the following capacities:
$1300 / 1.5 TB (87 cents/GB)
$1480 / 2.0 TB (74 cents/GB)
$1660 / 2.5 TB (66 cents/GB)
$1840 / 3.0 TB (61 cents/GB)
$2020 / 3.5 TB (58 cents/GB)
keep in mind thats a dedicated bulletproof pc with the ability to scale a 4-drive array up to 8 drives as drive price falls. the machine can also burn and verify 4 dvds at a time in under 10 minutes, while torrenting and not missing a beat. you can skimp and go with 2 drives, I very rarely burn more than 2 at a time even tho I have 4 drives.
the serial ata drives are pretty fast, the raid function doesnt really slow em down. I'm kind of worrying about fragmentation, as I'm using about 95% of my 1.2TB array.
I want to expand soon. i wish more people had large systems like this and we could synch 3.5 TB at a time, over LAN. the better sata cards have online capacity expansion so the array is expandable without rebuilding the volume (i.e you dont have to reformat). thats the one to get. highpoint rocketraids are pretty good, but there s a lot of models. there are two new types of incompatible hi-speed pci slots, so you have to make sure you get the right card for your mobo.
This system doesnt even require a fast computer, just fast drives. I have a lowly athlon 2000 ish mhz processor on a two-year old pci mobo, both from ebay. you dont really need much speed for a dedicated bt and media burning center.