Linux: Replace Disk in MD

Mon, 28 Dec 2015 00:00:00 +0000

On my lab machines I use a pair of physical disks, configured in a RAID 1 with MD, with LVM on top of that. This gives me a lot of flexibility with full redundancy. However recently I had a failure of a drive.

Identify the Failure

Here is what MD was telling me after I identified and removed the drive from the chassis to send it off for an RMA, notice how each device only has one member (md0 has sda1, md1 has sda2), this does not make a good RAID 1. But this is easily resolved.

Linux-LVM: Resize Partition to Grow LVM Volume Group

Mon, 20 Aug 2012 00:00:00 +0000

Logical Volume Manager makes the dynamic expansion of file systems dead stupid simple. However there is a weakness, if you are using a partitioned file system as your Physical Volume (PV) then you will end up needing to expand the file system if you ever need to grow the actual storage. This can be avoided by using the actual physical device /dev/sda as the PV, however if this is the same volume where your /boot partition lives then you will have no choice but to partition it out since /boot cannot reside on a Logical Volume (LV). The other way you can avoid this is by simply creating a second partition on the same disk and adding it as a new PV to the existing Volume Group (VG). This is preferable as there is far less room for error than in this procedure, but I personally find that method a little more confusing to inherit then a straight forward single partition made an LV.

Fdisk on the bin

Linux: Replace Disk in MD

Identify the Failure

Linux-LVM: Resize Partition to Grow LVM Volume Group