Suggestions for LVM sandboxing

Question

I want to do some testing involving LVM. Specifically, creating, destroying merging and splitting LVM Volume Groups.

But I don't have any spare physical volumes. I could create some, but that would be messy.

I imagine it's possible to create some kind of "virtual" physical volumes to use with LVMs. But I'm not sure of a clean way to do this. Suggestions appreciated. A detailed outline would be even more appreciated.

Answer 1

1. Install VirtualBox, VMware Player. Of course any other type 2 hypervisor can do the work)
2. Create virtual machine with bunch of disks (not need to be huge, 2-3-4GB will be fine)
3. Install Linux (or OS you want to play)
4. Create PVs, create VG(s), create LVs and start playing with LVM

P.S. You can try also to create files and use them as PVs to play with LVM. But if on your system you have already LVM in use I will not recommend play there.

The way to use files instead of disks or partitions in LVM is this:

1. Create files:

dd if=/dev/zero of=lvmtest0.img bs=1024 count=1M dd if=/dev/zero of=lvmtest1.img bs=1024 count=1M ...

2. Link them to loop interfaces:

losetup /dev/loop0 lvmtest0.img losetup /dev/loop1 lvmtest1.img

3. Create them as PVs

pvcreate /dev/loop0 /dev/loop1

And then start with creating VG, LVs and so on You can check this site for more information

The reason I do not recommend play with LVM on your machine if you already have LVM there is there is always possibility to execute wrong command and to mess with LVM volumes where your OS is installed/your files reside