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= LVM Linux volume management =
 * NOTE:201507: Rather look at [[linux/btrfs|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)
 * [[http://wiki.xtronics.com/index.php/Raid|#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 [[http://bisqwit.iki.fi/story/howto/undopvremove/|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

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CategoryLinux