Hard drive dilemma.

[jonowee]

Essentially this thread boils down to me trying to decide whether to buy 3.5" 1TB, 2TB, or 3TB hard drives?

So for the short term (till end of 2011 at current estimations) I think of running two HDDs to run in RAID 0, migrate the OS and everything off my current single 2TB Western Digital Green drive to the RAID array and use the Green drive as back up. In the long term I am in planning for a DIY 8 drive NAS-server, current planning shows the NAS to be even more expensive than 'workstation' main rig that I'm slowly upgrading around. Such is the high cost of the NAS tower is that certain tit bits like a TV tuner and a SSD will have to wait.

The plan for the NAS all along has be for eight 7200RPM 2TB drives; all kinds of ideas have been popping in and out; WD Greens, WD Blacks, Samsung F3s, Hitachi CinemaStars, and Hitachi DeskStars (feeling meh about Seagates).

Now more info to help you help me, you need to help me with everything in the brackets below:

Main rig:

Short term:

- 2x 3.5" 7200RPM (1TB, 2TB or 3TB) HDDs in RAID 0 for OS and main storage. 1TB keeps costs low, and together matches the capacity of the Green back up drive; post NAS build they can be hand me down drives at minimal cost to me. 2TB has life in the NAS build if used, but together they seem odd to larger than the back up drive. 3TB same story as 2TB, depends on whether I start with 2TB or 3TB on the NAS.

- 1x 3.5" 2TB WD Green for back up.

​

Long term:

- 1x 120GB (2.5" SSD or RevoDrive) for OS and programs.

- 1x 3.5" 7200RPM (1TB, 2TB or 3TB) HDDs for immediate access storage.

​

NAS-server:

Initial build:

- 8x 3.5" 7200RPM (2TB or 3TB) HDDs in RAID 6, so 12TB and 18TB of usable space respectively.

- 2x 4-in-3 3.5" SATA/SAS hot-swap backplanes​

Upgrades?:

- 8x 3.5" 7200RPM 3TB <4TB if they managed that in five years>, if starting with 2TB drives.

- Cost of short term data holding or engaging professional data migration services.

- There were ideas of expanding or starting to a 12/16 internal port RAID card, but the added cost of not utilising the extra 4-8 ports is wasted money, wasted time and more headaches juggling hard drives.

​

2TB or 3TB dilemma for the NAS-server.

Prices vary depending on who makes the drives and where I source them from, to keep things simple we'll stick with the drive manufacturer when weighing up my options. I will be sourcing the same HDDs from different resellers as to increase the chances of getting drives varying manufacture batches, and minimise the chance of exposing the array to too many 'bad batch' drives that could fail together.

As a rough price guide...

Hitachi DeskStar 7200RPM: 1TB $60, 2TB $120, 3TB $190.

Seagate Barracuda XT: 2TB $200, 3TB $280

Western Digital Green 1TB $65, 2TB $90, 3TB 7200 RPM $210.

Hitachi UltraStar and Seagate Constellation prices put them out of the question.

Remember, the costs of eight drives add up very quickly. For example, $50 extra per drive is $400 difference.

I almost called it quits for a Drobo Pro FS.

So your thoughts, ideas, and suggestions...

 

[Diablo]

I've done a project somewhat similar to this, in that I have a server with 5TB in a RAID 0 and a RAID 5 array. My advice would be to look at the price of hard disks exactly when you are building the system, but given the current prices, the 2TB drives look like the best option. As 3TB are much more expensive, they don't seem worth the money.

With regards to brands, that one is really up to you. In my current server, the data speed is limited by the network card - 1Gbps, not the disks. In that respect I doubt the green drives would slow things down unecessarily. As SATA III drives are coming out, it would be worth looking at RAID cards that support them, as it will make upgrades easier in the future.

Another factor you need to consider is the RAID card. An eight port card would be adequate (I run an adaptec 5808), but don't forget about a BBU. Your idea about sourcing drives from different locations is a good one, as it means that in the event of a disk failiure, if one reseller has gone out of buisness you will have some redundancy. It also means that you can pick and choose the resller to RMA things with depending on how easy they are to deal with.