Disc partitions, grub inside LVM and web migration in production server

Hi everyone! Beforehand sorry if my english isn’t accurate.

I manage a server with 2 virtual servers inside. One of them host a Wordpress and the other host a Moodle. They are in production, so I better not disconnect anything.

At first time, I set up my 3x1Tb HDD in RAID5. Then I set up a LVM for all the space. I thought this was the best way because if a HDD breaks I can put another and it recovers itself. I thinked this a robust implementation.

Days ago, the server didn’t boot anymore, I think it was a power network supply error. I have to call a friend to solve the problem (he puts the /boot in a USB and boot the server from there). He said that this implementation is not good and I have to create a RAID1 for the /boot and RAID5 for the rest.

Well, my problem is:
How I make this change?
Is better backup all virtualservers and make a clean install?
Have I got a way to repartitioning the HDD without change the configuration?

It probably is easiest to backup and start fresh. It is possible to resize all of the components (when booted from an extra disk), but it’s not easy to get all the steps right, and if you’re changing the underlying type of striping from LVM to md RAID5 and RAID1, as it sounds like you want to do, you’d need to start from scratch.

Note that LVM also has striping and mirroring capability and they aren’t necessarily inferior to the md RAID features (as far as I know). But, if you didn’t setup striping and mirroring and just used the naive combining of space across disks feature of LVM, you’d have to start over to get striping and mirroring turned on, I think.

So, yeah, if it were me, I would backup everything and do a fresh install; I would do both a full system backup and a Virtualmin backup.

Thank you Joe,

before I try this on the physical server I will try in a virtual machine/other machine.

I try to reproduce the same in my homelab and I don’t be able to restore the backup of one of the virtual servers. It says that the name is pointing to a url out off my domain.