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I'm afraid I won't be testing it any time soon -- I don't have any drives |
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to pair at the moment. As for your comments about dmraid being 'fake', I'm |
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a little confused. From what you say it sounds like this is the hardware |
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RAID that comes with many motherboards. Why is hardware RAID undesirable |
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over software RAID? Presumably the mdraid software option has an associated |
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performance hit? Is it just that opaque proprietary firmware can't be |
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trusted with the important task of looking after our data? |
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|
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On 6 July 2015 at 16:01, Peter Humphrey <peter@××××××××××××.uk> wrote: |
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|
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> On Monday 06 July 2015 10:19:36 Alex Thorne wrote: |
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> > I guess I did mean mdraid, but would you mind explaining the difference |
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> > (I've never used raid so don't know much about this)? Is dmraid |
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> deprecated |
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> > in favour of mdadm? |
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> |
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> Dmraid is the fake RAID that's included on most motherboards these days; |
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> it's |
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> meant for use with Windows and is enabled (or not) in the BIOS. There are |
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> Linux drivers, but we're always advised to use mdraid instead. Mdraid is |
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> all |
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> in software spread over the kernel, udev and user space*; it's not |
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> influenced |
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> at all by Windows as far as I know. Mdadm is the user-space administration |
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> program that comes with mdraid. |
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> |
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> Mdadm creates /dev/mdX from one or more /dev/sdX or similar - e.g. my |
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> /dev/md1 |
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> is built on /dev/sd[ab]1; /dev/md5 is on /dev/sd[ab]5 and /dev/md7 is on |
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> /dev/sd[ab]7. That last one also has LVM on it with a dozen or more logical |
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> volumes for segments of my overall file system. |
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> |
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> If you want to play with mdraid, the old Gentoo guide is succinct but |
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> useful: |
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> |
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> http://wwwold.gentoo.org/doc/en/gentoo-x86+raid+lvm2-quickinstall.xml |
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> |
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> Well, it was, but suddenly it isn't there - even Google's search results |
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> end |
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> up in an empty page. |
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> |
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> Ah, I've found the new version at https://wiki.gentoo.org/wiki/LVM . It |
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> must |
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> be very new - would you like to test it? :-) |
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> |
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> * Yes, I know that udev runs in user space (="User Device" management) |
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> but I |
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> thought it was worth mentioning separately. |
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> |
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> -- |
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> Rgds |
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> Peter |
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> |
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> |
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> |
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