On Monday 06 July 2015 10:19:36 Alex Thorne wrote: > I guess I did mean mdraid, but would you mind explaining the difference > (I've never used raid so don't know much about this)? Is dmraid deprecated > in favour of mdadm?
Dmraid is the fake RAID that's included on most motherboards these days; it's meant for use with Windows and is enabled (or not) in the BIOS. There are Linux drivers, but we're always advised to use mdraid instead. Mdraid is all in software spread over the kernel, udev and user space*; it's not influenced at all by Windows as far as I know. Mdadm is the user-space administration program that comes with mdraid. Mdadm creates /dev/mdX from one or more /dev/sdX or similar - e.g. my /dev/md1 is built on /dev/sd[ab]1; /dev/md5 is on /dev/sd[ab]5 and /dev/md7 is on /dev/sd[ab]7. That last one also has LVM on it with a dozen or more logical volumes for segments of my overall file system. If you want to play with mdraid, the old Gentoo guide is succinct but useful: http://wwwold.gentoo.org/doc/en/gentoo-x86+raid+lvm2-quickinstall.xml Well, it was, but suddenly it isn't there - even Google's search results end up in an empty page. Ah, I've found the new version at https://wiki.gentoo.org/wiki/LVM . It must be very new - would you like to test it? :-) * Yes, I know that udev runs in user space (="User Device" management) but I thought it was worth mentioning separately. -- Rgds Peter
