vgextend(1M)

NAME

vgextend − extend an LVM volume group by adding physical volumes

SYNOPSIS

/sbin/vgextend [-A autobackup] [-g pvg_name] [-x extensibility] vg_name pv_path ...

Remarks

vgextend cannot be performed if the volume group is activated in shared mode.

DESCRIPTION

The vgextend command assigns physical volumes to volume group vg_name. The volume group must be active.

Volume groups are extended by adding one or more physical volumes specified by pv_path ....

After the physical volumes have been successfully added to the volume group, they can be used.

Before assigning a physical volume to a volume group, create the physical volume with the pvcreate command (see pvcreate(1M)).

If, for any reason, a specified physical volume cannot be installed into the volume group, an error message is printed. However, the installation continues to the end of the list of physical volumes.

When a pv_path refers to one of the physical volumes already in the volume group by a different pv-link
name, this new path becomes an alternate pv-link to the physical volume. When multiple paths that reference the same disk are provided in the pv_path list, the order of the paths is important. The first path becomes the primary link to the physical volume, the second becomes an alternate link to the physical volume. The primary link is the path used to access the physical volume. If the primary link becomes unavailable, LVM automatically switches to the alternate link to access the physical volume.

Options and Arguments

vgextend recognizes the following options and arguments:

pv_path The block device path name of a physical volume.

vg_name The path name of the volume group.

-A autobackup Set automatic backup for this invocation of this command. autobackup can have one of the following values:

y Automatically back up configuration changes made to the volume group. This is the default.

After this command executes, the vgcfgbackup command (see vgcfgbackup(1M)) is executed for the volume group.

n Do not back up configuration changes this time.

-g pvg_name Extend an existing physical volume group while the volume group is being extended by adding all the physical volumes in the pv_path parameter to the physical volume group specified by pv_group_name.

If the specified physical volume group does not exist, it is created, thus providing a means for creating new physical volume groups after the volume group has been created. Another way to extend or add a physical volume group is to edit the /etc/lvmpvg file as described in vgcreate(1M). See lvmpvg(4) for format details.

-x extensibility Set allocation permission for additional physical extents on the physical volume specified by pv_path. extensibility can have one of the following values:

y Allow allocation of additional physical extents on the physical volume.

n Prohibit allocation of additional physical extents on the physical volume. Logical volumes residing on the physical volume can still be accessed.

EXTERNAL INFLUENCES

Environment Variables

LANG determines the language in which messages are displayed.

If LANG is not specified or is null, it defaults to "C" (see lang(5)).

If any internationalization variable contains an invalid setting, all internationalization variables default to "C" (see environ(5)).

EXAMPLES

Add physical volumes /dev/dsk/c0t1d0 and /dev/dsk/c0t2d0 to volume group /dev/vg03:

vgextend /dev/vg03 /dev/dsk/c0t1d0 /dev/dsk/c0t2d0

Extend physical volume group PVG0 while adding physical volumes /dev/dsk/c0t3d0 and /dev/dsk/c0t4d0 to volume group /dev/vg03:

vgextend -g PVG0 /dev/vg03 /dev/dsk/c0t3d0 /dev/dsk/c0t4d0

Add a PV link to one of the physical volumes in the volume group. Where /dev/dsk/c0t4d0 and /dev/dsk/c1t4d0 refer to the same physical volume (referenced via different controllers), and the volume group already contains /dev/dsk/c0t4d0. /dev/dsk/c0t4d0 remains the primary link (in use) and /dev/dsk/c1t4d0 becomes an alternate link.

vgextend /dev/vg03 /dev/dsk/c1t4d0

WARNINGS

It is not possible to extend a volume group such that it contains both HP-IB devices and devices that use another type of interface.

The new physical volume which has been added to the volume group could potentially have different block size compared to physical volumes already in the volume group.

If a logical volume created on two or more physical volumes which have different block size, it is not possible to use such logical volume for file system purposes. See extendfs(1M).

For example, when a logical volume contains physical volumes that all have 1k block size, and then it is extended to contain a physical volume with 2k block size, then the block size of the volume group is increased to 2k.

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