To RAID or Not to RAID
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Ken Warren wrote: - Make one of your 500 GB drives as the system drive. It will deliver a better user experience.
- Make the other 3 500 GB drives a RAID 5 array.
On my non-stock WHS box, I did virtually the complete opposite. I made a 4x250G RAID5 array for the primary drive and used a 320G drive as the data drive. I was interested in performance and fault tolerance. By doing it this way I ended up with ~700G for C and D (also resized) with 320 available for replication. Even if I add 500G drives later, the primary will still be the largest drive, as suggested. Without the array, the largest drive would only be 320G and I'd have ~300G more but it'd be slower.
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The "sweet spot" isn't Microsoft canon, it's a personal theory, based on observation.
Let's say you work with large amounts of data on a daily basis, to the tune of 20 GB or more a day. There's really no need for any part of WHS to be able to manage more than that amount of data in a single pop. If you can copy 20 GB to the server in one shot, and Drive Extender can move that data off to secondary drives in a timely fashion, then you're unlikely to ever need to worry if you keep 100 GB free in your D: partition.
Where having more space available helps is in the initial loading of WHS. If you want to copy several hundred GB to the server in one shot, the larger your system drive is, the better. But then all that space sits unused afterward.
Even backups shouldn't cause issues, because they get split up into multiple smaller (4 GB) files. DE has to handle them, but I believe a given file in the backup database is left idle once it's full, until the weekly backup cleanup on Sunday mornings. If so, a relatively small number of backup files will be "active" at any time, probably one file per machine for indexes and two or three backup database files.
A system disk of 160 GB is perfectly adequate for my use of WHS. I've never come close to filling that up before DE gets a chance to migrate files off to secondary disks, and even backups of my own desktop PC, with a couple of hundred GB of data being backed up, never cause a hiccup.
Your mileage will vary a bit, of course.
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Yes, and that's the advice I will normally give, because most users don't currently have the plethora of drives that you and I do.
SME wrote: I understand that it's just a personal theory, it's just that I've never heard such a theory before. As I've said, everything (prior) that I've read always suggests using the largest drive for the system drive.
True, and good catch. I should have specified "assuming sufficient space in the storage pool to completely clear the D: partition."SME wrote: That space wouldn't be unused if replication is on with a 2 drive WHS system. Right?
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Raid wrote: Thank you very much for the assistance provided. Yours and other responses provided a detailed tutorial that certainly expanded my knowledge on the subject.
Glad it helped but, really, we just scratched the surface of the entire RAID debate.
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abobader wrote: That not totally correct.
RAID never meant as protection when it made in the mid of 80's.
Speed search, cost effected, and the most important, "uptime", well, from the name of it as you know:
There you go making stuff up again.
Allow me to use a source, more your speed:
http://en.wikipedia.org/wiki/RAID
computer storage, a Redundant Array of Independent Drives (or Disks), also known as Redundant Array of Inexpensive Drives (or Disks), (RAID) is an umbrella term for data storage schemes that divide and/or replicate data among multiple hard drives. RAID can be designed to provide increased data reliability and/or increased I/O performance.
Norman Ken Ouchi at IBM was awarded a 1978 U.S. patent 4,092.732[1] titled "System for recovering data stored in failed memory unit." The claims for this patent describe what would later be termed RAID 5 with full stripe writes.
Hope that helps...
