[CentOS] raid on large disks?

Wed Oct 12 16:55:01 UTC 2011
John R Pierce <pierce at hogranch.com>

On 10/12/11 9:36 AM, Les Mikesell wrote:
> LVM seems unnecessarily complicated unless mdraid is broken on large
> devices.   And I already have data on the md partition (moving stuff
> from a pair of 1.5TB drives to 3TB).  If md isn't going to work, can I
> put LVM on a single drive, add the data, then add the mirror (reusing
> the one that now has the md partition and currently holding the data)?
>   The old disks are still around but not in the machine now.

I believe (from memory) you'd add the 2nd drive to the volume group, then

     vgextend vgname /dev/(newdisk)
     lvconvert -m 1 logicalvolumename

one nice thing about lvm mirroring is you can do it with a mix of drive 
sizes without having to worry about geometry or layout, it will simply 
ensure that each block exists on two devices....

john r pierce                            N 37, W 122
santa cruz ca                         mid-left coast