Emergency UNIX and Linux Support

Hi.
I thought that I had read some time ago, that LVM on top of MD was a good solution. In fact, that is what I had done the last time I installed Linux on a standalone machine (not a VM) recently.

One reference provides some of the background: RAID verses LVM - Stack Overflow

Some other sources, mainly for the procedures of installing LVM on top of MD: Setup Software Raid 1 with LVM on Linux , https://wiki.archlinux.org/index.php...re_RAID_or_LVM ,

Some performance numbers are available at https://raid.wiki.kernel.org/index.php/Linux_Raid

I don't recall seeing advice to shift over to RAID via LVM as opposed to MD. One reason (for me) is that MD has the ability to do RAID10, and (so far) LVM does only RAID0 and RAID1. Also grub has not traditionally understood LVM, so the boot partition cannot be LVM.

However, I have used rsync to backup LVM partitions and it makes use of snapshots to do the work -- very nice feature so that you don't need to take down the machine to backup.

cheers, drl

Excepting LVM is more about volume management and less about resilience, LVM does not AFAIK have the tools to setup a RAID5 or RAID6 environment. Instead you'd have to build LVM on top of RAID which in my opinion leads to a new level of complexity if you need to do a recovery.

LVM is good for environments where you might have lots of data spread over lots of disks, however where you need your data to be as safe as practicable with reasonably efficient usage of drives RAID5 or RAID6 is probably the way to go.

Anyways I managed to get the RAID array back up, copied the data off it, got another drive to allow me to make the array RAID6 and re created a new RAID6 array. I'm currently copying 9TB back onto the array.

Disks were so much faster when they were 28" in diameter and held 100M !