restmilliondollar.blogg.se - External volume manager

EXTERNAL VOLUME MANAGER SOFTWARE
EXTERNAL VOLUME MANAGER WINDOWS

3rd Party software may allow to mount certain kinds of LVM setups.

EXTERNAL VOLUME MANAGER WINDOWS

If dual-booting, note that Windows does not support LVM you will be unable to access any LVM partitions from Windows.Requires (multiple) daemons to constantly run. Additional steps in setting up the system, more complicated.

Built-in support for caching of frequently used data ( lvmcache(7)).

Support for unlocking separate volumes without having to enter a key multiple times on boot ( make LVM on top of LUKS).

Snapshots allow you to backup a frozen copy of the file system, while keeping service downtime to a minimum.

Online/live migration of LV being used by services to different disks without having to restart services.

File systems on them still need to be resized, but some (such as ext4) support online resizing.

Resize/create/delete logical and physical volumes online.

It does not depend on the position of the LV within VG, there is no need to ensure surrounding available space.

Resize logical volumes regardless of their order on disk.

Create small logical volumes and resize them "dynamically" as they get filled up.

Have logical volumes stretched over several disks.

Use any number of disks as one big disk.

LVM gives you more flexibility than just using normal hard drive partitions: fstab) since the latter is intended for "internal use" and subject to possible "change between releases and distributions". However, lvm(8) § VALID NAMES recommends the former format for "software and scripts" (e.g.

Note: Logical volumes are accessible at both /dev/ VolumeGroupName/ LogicalVolumeName and /dev/mapper/ VolumeGroupName-LogicalVolumeName. │ /dev/MyVolGroup/rootvol │ /dev/MyVolGroup/homevol │ /dev/MyVolGroup/mediavol │ │ Logical volume1 15 GiB │ Logical volume2 35 GiB │ Logical volume3 200 GiB │ Volume Group1 (/dev/MyVolGroup/ = /dev/sda1 + /dev/sda2 + /dev/sdb1): │ Partition1 50 GiB (Physical volume) │ Partition2 80 GiB (Physical volume) │ Think of PEs as parts of PVs that can be allocated to any LV. Physical extent (PE) The smallest contiguous extent (default 4 MiB) in the PV that can be assigned to a LV. they can be directly formatted with a file system. LVs are Unix block devices analogous to physical partitions, e.g. Logical volume (LV) "Virtual/logical partition" that resides in a VG and is composed of PEs. Volume group (VG) Group of PVs that serves as a container for LVs. Examples: a hard disk, an MBR or GPT partition, a loopback file, a device mapper device (e.g. Physical volume (PV) Unix block device node, usable for storage by LVM. Virtual partitions allow addition and removal without worry of whether you have enough contiguous space on a particular disk, getting caught up fdisking a disk in use (and wondering whether the kernel is using the old or new partition table), or, having to move other partitions out of the way. With LVM you abstract your storage and have "virtual partitions", making extending/shrinking easier (subject to potential filesystem limitations). Logical Volume Management utilizes the kernel's device-mapper feature to provide a system of partitions independent of underlying disk layout. Logical Volume Manager (LVM) is a device mapper framework that provides logical volume management for the Linux kernel. Create root filesystem snapshots with LVMįrom Wikipedia:Logical Volume Manager (Linux):.dm-crypt/Encrypting an entire system#LUKS on LVM.dm-crypt/Encrypting an entire system#LVM on LUKS.