{{tag>Brouillon FS LVM}}

= Notes LVM

Voir :
* [[boot-lvm-grub]]
* [[lvm_changement_remplacement_de_pv]]
* [[vm_creation_fs_lvm_a_chaud]]
* [[snapshot_lvm]]

lv_attrs
<code bash>
man 8 lvs
</code>

Extents are the smallest units of space that you can allocate in LVM. Physical extents (PE) and logical extents (LE) has the default size of 4 MiB that you can configure. All extents have the same size. When you create a logical volume (LV) within a VG, LVM allocates physical extents on the PVs


== Création LVs

<code bash>
lvcreate -l 100%FREE -n newlv vg_data
</code>

== Script - get size lv_size & vgfree space

<code bash>
lvs --readonly --noheadings --nosuffix --units=m /dev/mapper/applivg-lv_plop -o lv_size
vgs --readonly --noheadings --nosuffix --units=m applivg -o vgfree
</code>




== Pb 

<code ->
# pvcreate /dev/sda3
  Device /dev/sda3 not found (or ignored by filtering).
</code>
  
<code ->
# pvcreate -vvv /dev/sda3 2>&1|grep '/dev/sda3'
        /dev/sda3: Skipping: Too small to hold a PV
</code>


== Tags

<code bash>
vgchange --deltag T9 --deltag T10 --addtag T13 --addtag T14 grant

pvs -o pv_tags /dev/sda2
vgs -o vg_tags /dev/VolGroup00
lvs -o lv_tags /dev/VolGroup00/LogVol00
</code>

Use the following command to list all the logical volumes with the database tag
<code bash>
lvs @database
</code>

Use the following command to list the currently active host tags
<code bash>
lvm tags
</code>

== Autres

Resize the PV when some data was allocated at the end of the LVM.

<code bash>
pvs -v --segments /dev/sda5
pvmove --alloc anywhere /dev/sda5:yyyy-end
pvs -v --segments /dev/sda5
</code>