LVM

Logical Volume Management on Linux

Link

• How do you clone an lvm partition?
• HOWTO
• Beginner's guide to LVM
• Resizing LVM + DRBD
• http://wiki.tldp.org/LVM-on-RAID
• LVM nesting
• http://blog.gadi.cc/better-lvm-for-kvm/

NOTE: remember to add snapshot support when calling lvcreate

Related commands

create physical volume

pvcreate /dev/sda3

lvcreate

lvcreate -L12G -nmyvol myvolumegroup
lvcreate -l 100%FREE -nmyvol myvolumegroup

lvresize

lvresize --resizefs -L-2G /dev/vg/foo

FAQ

Access logical volumes within logical volume

partprobe /dev/mapper/vg-mydata
lsblk

This will show the (sub) partitions/volumes, then edit /etc/lvm/lvm.conf

filter = [ "a|.*/|", "a|mydata|","r|.*|" ]

Then run:

vgscan
lvscan
vgs

Now you should see the names of the volumes you're looking for, so now:

vgchange -a y guestsname_mydata-home

and then you should be able to

mount /dev/mapper/guestsname_mydata-home

When done, remember to change back the filter in lvm.conf, default is

filter = [ "a|.*/|" ]

and of course then once again

vgscan
lvscan

Add disk to pg

pvcreate /dev/sdc
vgextend MYVG /dev/sdc
lvextend /dev/NYVG/mylv /dev/sdc

And then grow fs

lvremove: Logical volume vg-kvm/vps-snapshot is used by another device.

???

• http://naveen161089.blogspot.nl/2014/03/forcefully-remove-lvm.html

some say lvchange -an the snapshot first, but that disables the lv it's connected to as well

Grow physical volume

Assuming your LVM partition is the last one, use fdisk to delete and recreate it, remember to set type to LVM again and reboot. Then use pvresize /dev/sdaX

Remove physical drive from a volume group

Make sure the data fits on remaining drive, then

pvmove /dev/sdbX
vgreduce /dev/sdbX