LEARN ABOUT LVM SUPPORT IN LINUX

As Linux has progressed, its feasibility in large-scale enterprise systems has increased. One of the reasons for this is Logical Volume Manager (LVM) support. LVM is a means for creating a file system that spans more than one physical device or partition.

For instance, traditionally you would create separate /, /home, /var, etc., partitions. However, with this, you are restricted to certain defined sizes when you create partitions. If you lack foresight, you might be stuck with partitions that are too small for your needs.

For instance, your /var partition may host your Web and FTP data; over time, you may find that it doesn't have room enough to store all of your data. The solution is to juggle data around by reorganizing your file systems and adding new drives.

LVM easily takes care of this problem. For instance, if you have one partition designated as /var, which is becoming too full, you could use LVM to simply throw in another hard drive, create another partition on the drive, and combine the two partitions to create one large /var directory tree that spans multiple devices. The benefit is obvious: easier administration of your file system.

To use LVM, you must have multidevice support (RAID and LVM) enabled in your Linux kernel. The partitions you use as LVM-enabled cannot be the traditional Linux partition type, but must be Linux LVM (code 8e). You can accomplish this by using fdisk to change partition types. You would then use a variety of LVM tools to create, manage, and administer your LVM systems. You can find out more about LVM online.

http://www.sistina.com/products_lvm.htm