PDA

View Full Version : Array over 2TB


J-Mag
12-02-08, 02:28 PM
Has anyone used software RAID on an array over 2TB and does this limit include parity data? Essentially, is it possible to skirt the whole issue with three 1TB drives in RAID 5, since the array will only have 2TB addressable?

Q
12-02-08, 02:30 PM
I have 5 500GB drives in a RAID 5 and have 1.8 or so TB available with no problems.

Bman212121
12-02-08, 02:37 PM
Has anyone used software RAID on an array over 2TB and does this limit include parity data? Essentially, is it possible to skirt the whole issue with three 1TB drives in RAID 5, since the array will only have 2TB addressable?

2TB limit of what? I can't say as I've heard of a 2TB limit unless your formatting it as FAT32. What OS would you be using?

Q
12-02-08, 02:43 PM
2TB limit of what? I can't say as I've heard of a 2TB limit unless your formatting it as FAT32.

http://technet.microsoft.com/en-us/library/cc773268.aspx

Bman212121
12-02-08, 02:48 PM
http://technet.microsoft.com/en-us/library/cc773268.aspx

Heh I have that same KB article open right now. It sounds like 2000 / XP 32bit would be effected. If you have XP 64bit, Server 2003 or above, or Vista you can format NTFS using GUID Partition Tables.



Breaking 2TB Option 1 - Use Windows with NTFS and GUID Partition Tables (GPT) partitions. It is possible for Windows to use NTFS partitions larger than 2TB as long as they are configured properly. Windows requires that the GUID Partition Tables be used in place of the standard Master Boot Record (MBR) partition tables. You will need Windows XP x64 Edition or Windows Server 2003 Service Pack 1, Windows Vista, or later for GPT support. (It is possible to mount and read existing GPT partitions under Windows XP and 2000 using GPT Mounter from Mediafour.; however, their MacDrive product does not support GPT partitions.) There are a couple of stipulations for GPT disks. First, the system drive on which Windows is installed can't be a GPT disk because it is not possible to boot to a GPT partition. Secondly, an existing MBR partition can't be converted to GPT unless it is completely empty; you must either delete everything and convert or create the partition as GPT. Read this Microsoft TechNet article for more details on GPT.


http://www.carltonbale.com/2007/05/how-to-break-the-2tb-2-terabyte-file-system-limit/

Q
12-02-08, 02:57 PM
Yeah, but you can't boot to a GPT unless you have an EFI based BIOS. As long he's not booting to it he would be fine with GUID and over 2TB.

Bman212121
12-02-08, 03:00 PM
Good to know. :thumbsup:

J-Mag
12-02-08, 03:06 PM
I have 5 500GB drives in a RAID 5 and have 1.8 or so TB available with no problems.

What RAID controller are you using?


Yeah, but you can't boot to a GPT unless you have an EFI based BIOS. As long he's not booting to it he would be fine with GUID and over 2TB.

Also, it looks like if you want to use Vista and boot to a 2TB+ array you need to run the 64bit version: http://support.microsoft.com/kb/946557

How can I determine if my BIOS is EFI based, aren't most new boards?

Q
12-02-08, 03:32 PM
What RAID controller are you using?




Also, it looks like if you want to use Vista and boot to a 2TB+ array you need to run the 64bit version: http://support.microsoft.com/kb/946557

How can I determine if my BIOS is EFI based, aren't most new boards?

I'm using the crappy Intel ICH9R Soft/Driver raid.

You do need the 64-bit version of Windows AND an EFI based board. Actually, most new boards are still BIOS based. I don't know of any desktop EFI based motherboards on the market right now.

J-Mag
12-02-08, 03:47 PM
I'm using the crappy Intel ICH9R Soft/Driver raid.


Did you need to format yours as GPT?


You do need the 64-bit version of Windows AND an EFI based board. Actually, most new boards are still BIOS based. I don't know of any desktop EFI based motherboards on the market right now.

I'm not sure what i was thinking, there isn't much of a major benefit to booting to these large arrays, unless you are pressed for case space.

einstein_314
12-03-08, 12:38 AM
Maybe a small point....but why would you want to boot to a 2TB+ partition???? There is no way anyone in their right mind would do such a thing....

rage10
12-03-08, 02:32 AM
Well if you have several multi platter drives, you can get over 2 TB in raid 0 and have a really fast system. you don't necessarily have to use all the space either.

Q
12-03-08, 10:11 AM
Did you need to format yours as GPT?

It's currently GPT, but I'm not sure if it was a requirement or not. The array is in my home server...it was "set it and forget it".

Monolyth
12-03-08, 10:57 AM
You will of course need to have an empty array to use GPT.

AdamK47
12-03-08, 01:39 PM
Maybe a small point....but why would you want to boot to a 2TB+ partition???? There is no way anyone in their right mind would do such a thing....

I would. I boot to a single 1.5TB partition on a Seagate 1.5TB drive.