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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 deprecated |
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> in favour of mdadm? |
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Dmraid is the fake RAID that's included on most motherboards these days; 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 all |
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in software spread over the kernel, udev and user space*; it's not 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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Mdadm creates /dev/mdX from one or more /dev/sdX or similar - e.g. my /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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If you want to play with mdraid, the old Gentoo guide is succinct but useful: |
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http://wwwold.gentoo.org/doc/en/gentoo-x86+raid+lvm2-quickinstall.xml |
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Well, it was, but suddenly it isn't there - even Google's search results end |
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up in an empty page. |
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Ah, I've found the new version at https://wiki.gentoo.org/wiki/LVM . It must |
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be very new - would you like to test it? :-) |
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* Yes, I know that udev runs in user space (="User Device" management) but I |
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thought it was worth mentioning separately. |
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-- |
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Rgds |
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Peter |
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