X-Git-Url: https://git.proxmox.com/?p=pve-docs.git;a=blobdiff_plain;f=local-lvm.adoc;h=2489b9d140d83b7c036ccaf4762986a6a43568d1;hp=c5872befed40ebae98bee483ef0474cb2af3aea9;hb=856993e4166495537f42e0b9c3a51c966227feab;hpb=a69bfc83f6d2b79e94eeb39781d89b720b4482dc;ds=sidebyside diff --git a/local-lvm.adoc b/local-lvm.adoc index c5872be..2489b9d 100644 --- a/local-lvm.adoc +++ b/local-lvm.adoc @@ -1,3 +1,4 @@ +[[chapter_lvm]] Logical Volume Manager (LVM) ---------------------------- ifdef::wiki[] @@ -40,6 +41,13 @@ data:: This volume uses LVM-thin, and is used to store VM images. LVM-thin is preferable for this task, because it offers efficient support for snapshots and clones. +For {pve} versions up to 4.1, the installer creates a standard logical +volume called ``data'', which is mounted at `/var/lib/vz`. + +Starting from version 4.2, the logical volume ``data'' is a LVM-thin pool, +used to store block based guest images, and `/var/lib/vz` is simply a +directory on the root file system. + Hardware ~~~~~~~~ @@ -57,3 +65,74 @@ Bootloader We install two boot loaders by default. The first partition contains the standard GRUB boot loader. The second partition is an **E**FI **S**ystem **P**artition (ESP), which makes it possible to boot on EFI systems. + + +Creating a Volume Group +~~~~~~~~~~~~~~~~~~~~~~~ + +Let's assume we have an empty disk `/dev/sdb`, onto which we want to +create a volume group named ``vmdata''. + +CAUTION: Please note that the following commands will destroy all +existing data on `/dev/sdb`. + +First create a partition. + + # sgdisk -N 1 /dev/sdb + + +Create a **P**hysical **V**olume (PV) without confirmation and 250K +metadatasize. + + # pvcreate --metadatasize 250k -y -ff /dev/sdb1 + + +Create a volume group named ``vmdata'' on `/dev/sdb1` + + # vgcreate vmdata /dev/sdb1 + + +Creating an extra LV for `/var/lib/vz` +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +This can be easily done by creating a new thin LV. + + # lvcreate -n -V / + +A real world example: + + # lvcreate -n vz -V 10G pve/data + +Now a filesystem must be created on the LV. + + # mkfs.ext4 /dev/pve/vz + +At last this has to be mounted. + +WARNING: be sure that `/var/lib/vz` is empty. On a default +installation it's not. + +To make it always accessible add the following line in `/etc/fstab`. + + # echo '/dev/pve/vz /var/lib/vz ext4 defaults 0 2' >> /etc/fstab + + +Resizing the thin pool +~~~~~~~~~~~~~~~~~~~~~~ + +Resize the LV and the metadata pool can be achieved with the following +command. + + # lvresize --size + --poolmetadatasize + / + +NOTE: When extending the data pool, the metadata pool must also be +extended. + + +Create a LVM-thin pool +~~~~~~~~~~~~~~~~~~~~~~ + +A thin pool has to be created on top of a volume group. +How to create a volume group see Section LVM. + + # lvcreate -L 80G -T -n vmstore vmdata