LVM Linux volume management

• NOTE:201507: Rather look at BTRFS, it is reasonably mature, and does most thins lvm is used for.

• All Harddrives(HD's = pv=physicalvolumes) are put into a vg(volume group = 1big virtual hd) and then you partion it into lv's(logical volumes)

• #Installing_Debian_with_SATA_based_RAID

Why ?

• LV's can migrate while live - e.g. remove a disk
• LV's can expand while live

Notes

vgchange -a n
vgscan --mknodes (may not be necessary, but won't hurt)
vgexport -a
vgimport -a
vgchange -a y

That should bring them back to life.

• Undo a lvm mistake ball by ball

2021 Grow LVM

1. Increase the disk (e.g. AWS resize)

2. On linux check that size is visible with

   lsblk
   xvdf             202:80   0 1000G  0 disk
   └─xvdf1          202:81   0  500G  0 part
     └─home         253:0    0  500G  0 lvm  /home

3. If partition used for LVM grow it to full size, param: diskname <partition #>

   growpart /dev/xvdf  1

4. Grow lvm physical volume

   pvs
   pvresize /dev/xvdf1
   pvs

5. Grow volume group

   vgs

6. Grow actual volume (--resizefs also resizes underlying filesystem)

   lvextend --resizefs --extents +100%FREE </dev/<lvg>/volume name>
   df -h

2020 add disk to existing centos Linux

• Start PV /dev/sda2, then using vmware extend disk, using fdisk /dev/sda add additional partition /dev/sda3
• Add /dev/sda3 as PV $ sudo pvcreate /dev/sda3

• Add PV to VG vgextend [vgname] /dev/sda3 $ sudo vgextend vg_<xyz> /dev/sda3

• vgdisplay [vg)<xyz>]

• add free space in VG to LV $ sudo lvextend -L+20G /dev/vg_xyz/lv_root

CategoryLinux