Lead Image © grafner, 123RF.com

Manage logical volumes with GUI tools

Fair Serving

Article from ADMIN 41/2017

By Erik Bärwaldt

Linux uses the Logical Volume Manager to manage large hard drives and mass storage clusters efficiently. We look at various graphical tools that help serve up logical volumes and volume groups.

Conventional partitioning is reaching its limits with the increasing storage capacity of hard disks and solid-state drives (SSDs). If several physical mass storage devices are attached to clusters or larger standalone servers, you can manage them more conveniently with the Linux Logical Volume Manager (LVM). Even small servers or single-user systems benefit from LVM if you are planning to change a configuration or install additional hard drives in the future.

Well Grouped

LVM adds an abstraction layer between mass storage and its partitions and filesystems. You can thus combine several mass storage devices or physical volumes with LVM in a volume group and then address them as a unit. If only one mass storage device is available, you can set up one or more volume groups on it and then create logical volumes that also contain the respective filesystems. The smallest units of a logical volume system are the physical extents (4MB by default), which are comparable to sectors in classical partitioning schemes.

If you want to add additional mass storage, you retroactively grow the volume groups. The individual logical volumes can grow or shrink as needed, without the need to reconfigure the storage media or recreate the filesystem. It should be noted that the filesystem does not always permit growing and shrinking: Some modern candidates (e.g., XFS [1], JFS [2]) can only grow volumes in the mounted state, not shrink them.

Linux LVM also lets you rearrange data on the fly, which allows hot-swappable configurations, for example, in cluster environments. You can optimize the configuration of your mass storage for performance or safety through different distribution and mirror functions (see the "LVM and RAID" box). LVM Snapshots let you save certain defined conditions and

...

Use Express-Checkout link below to read the full article (PDF).