BYTE Magazine > Serving With Linux > 2000 > July

Some Command Examples

(A Logical Volume Manager For Linux, Finally!:  Page 3 of 3 )

By Moshe Bar

July 6, 2000

		In This Article
			A Logical Volume Manager For Linux, Finally! Inside LVM Some Command Examples

Assuming you have kernel 2.3.49+ or patched your existing kernel with the LVM drivers, you can run the following command examples to do some of the things mentioned above.

1. After installing LVM do an "insmod lvm" or setup kerneld/kmod to load it automatic (see INSTALL).

2. Set up partitions (#1) on both disks with partition type 0x8e.

3. Do a "pvcreate /dev/sd[ce]1" (For testing purposes, you can use more than one primary and/or extended partition on a disk. Don't do that for normal LVM operation for performance reasons. If you have to, don't stripe logical volumes over physical volumes associated to partitions on the same disk.

4. Do a "vgcreate volg02 /dev/sd[ce]1" (vgcreate activates the volume group too).

5. Do a "lvcreate -lvoldbf-_lv tvolg02" to get a 100-MB linear lvol or a "lvcreate -i2 -I4 -l1000 -nlvoldbf volg02" to get a 1,000-MB large lvol with two stripes and stripesize 4 KBs.

6. Use created LVs as needed. For example, generate a file system in one with "mke2fs /dev/volg02/lvoldbf" and mount it.

Because the Linux LVM follows closely the HP-UX concept, the commands are almost identical in name and behavior. So, the commands for physical volume handling all start with pv, those for volume group handling start with vg, and those for logical volumes start with lv.

TABLE 1 - LVM commands