vgchange.1m (2010 10)

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vgchange(1M) vgchange(1M)

NAME

vgchange - set LVM volume group availability

SYNOPSIS

Activate volume group

/usr/sbin/vgchange -a

availability [-A autobackup ][-T

][-l][-f][-p][-q quorum][-s

]

[

-P resync_daemon_count][vg_name ... ]

Set volume group high-availability cluster attributes

/usr/sbin/vgchange -c

cluster [-S sharable ] vg_name

Change activation mode of sharable volume group

/usr/sbin/vgchange -a

availability -x {vg_name ...}

Quiesce an active volume group

/usr/sbin/vgchange -Q

quiesce_mode [-t quiesce_time ] vg_name

Resume a quiesced volume group

/usr/sbin/vgchange -R

vg_name

Remarks

Serviceguard cluster operations require the installation of the optional Serviceguard software, which is

not included in the standard HP-UX operating system.

Mirrored disk operations require the installation of the optional HP MirrorDisk/UX software, which is not

included in the standard HP-UX operating system.

If a combination of volume groups version 1.0 and 2.0 or higher arguments are supplied, then the argu-

ments may not be processed in the order they are listed on the command line.

DESCRIPTION

The

vgchange command with the -a option activates or deactivates one or more volume groups.

For volume groups that are used in a high availability cluster, when the

-a option is speciﬁed together

with the -x option, the vgchange command allows cross-activation, changing the activation mode of an

active sharable volume group directly to the speciﬁed activation mode, without ﬁrst having to deactivate

the volume group.

The

vgchange command with the -c speciﬁes whether the indicated volume group(s) can be used in a

high availability cluster, optionally the -S option can also be speciﬁed to conﬁgure whether the volume

group is sharable (or is for exclusive activation only).

The

vgchange command without the -P resync_daemon_count option (default) will spawn one

nomwcsyncd process for each volume group containing

NOMWC logical volumes, and this can degrade sys-

tem performance when many of these volume groups are activated at the same time. The -P

resync_daemon_count option provides a way to control the number of concurrent nomwcsyncd processes

spawned. This parameter is advisory, LVM may use a different value internally as necessary.

The

-Q option allows quiescing an active volume group to facilitate creating a consistent disk snapshot

copy of all the physical volumes in the volume group. Metadata on the physical volumes is brought

current and remains unchanged until normal operation is resumed using the -R option (or when the

optionally speciﬁed -t quiesce_time time has expired).

Specifying

-Q rw when quiescing the volume group quiesces application reads and writes to the volume

group. This mode is suitable for most situations.

Specifying

-Q w when quiescing the volume group quiesces application writes to the volume group while

allowing reads to proceed as usual. This mode provides improved access to the data when used with

applications that are capable of quiescing updates while allowing queries. See the Quiesced Volume

Groups section for a more complete description of quiesced volume groups.

vg_name must be deﬁned as a volume group in the ﬁle

/etc/lvmtab or /etc/lvmtab_p.Ifvg_name

is omitted, all volume groups deﬁned in /etc/lvmtab and /etc/lvmtab_p are affected, except when

the -c, -x, -Q,or-R options are speciﬁed. Only a single volume group can be provided with these

options.

HP-UX 11i Version 3: October 2010 − 1 − Hewlett-Packard Company 1

Summary of content (8 pages)

PAGE 1
vgchange(1M) vgchange(1M) NAME vgchange - set LVM volume group availability SYNOPSIS Activate volume group /usr/sbin/vgchange -a availability [-A autobackup ] [-T] [-l] [-f] [-p] [-q quorum] [-s] [-P resync_daemon_count ] [vg_name ... ] Set volume group high-availability cluster attributes /usr/sbin/vgchange -c cluster [-S sharable ] vg_name Change activation mode of sharable volume group /usr/sbin/vgchange -a availability -x {vg_name ...
PAGE 2
vgchange(1M) vgchange(1M) High Availability Cluster Overview Volume groups can be defined on disk volumes that are accessible by more than one system in a high availability cluster. This situation has a high potential for data corruption unless higher level cluster software services are used to coordinate shared access to the same volume group by all systems. A volume group can be marked as part of a cluster.
PAGE 3
vgchange(1M) vgchange(1M) If a volume group is marked as part of a high availability cluster, the high availability software must be running on the system; otherwise, the volume group is not activated. n Deactivate each specified volume group and its associated logical volumes. You must close the logical volumes prior to executing this option. For example, if the logical volume contains a file system, the file system must be unmounted. For volume group version 2.
PAGE 4
vgchange(1M) vgchange(1M) -x Cross-activate a active sharable volume group, changing the activation mode to the specified activation mode. This option is only valid when used with the -a availability option. Cross-activation can only be used to change the activation mode from shared mode to exclusive mode, or from exclusive mode to shared mode. -A autobackup Set automatic backup for this invocation of vgchange.
PAGE 5
vgchange(1M) vgchange(1M) Shared Volume Group Considerations Volume group version 2.2 and higher with snapshot logical volumes configured cannot be actived in shared mode. See lvm(7) for information on snapshot volumes.
PAGE 6
vgchange(1M) vgchange(1M) Deactivate volume group /dev/vg03: vgchange -a n /dev/vg03 Forced deactivation of volume group /dev/vg03: vgchange -a n -f /dev/vg03 Activate volume group /dev/vg03 using multiple parallel threads: vgchange -a y -T /dev/vg03 Activate volume group /dev/vg03 without synchronizing extents that are not current on logical volumes that have Mirror Write Cache turned on: vgchange -a y -s /dev/vg03 Exclusive Activation Set up volume group /dev/vg03 for use in a high availability clus
PAGE 7
vgchange(1M) vgchange(1M) other systems can use read-only access. There is no problem if all systems activate the volume group for read-only access. Furthermore, volume group information is only read from the disks during volume group activation. Dynamic changes to the volume group such as the following are not propagated to other systems sharing the volume group: Logical volume configuration changes. Changes to the status of the mirrored extents. Bad-block relocation that occurs during write operations.
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(Notes) A (Notes) vA 8 Hewlett-Packard Company −1− HP-UX 11i Version 3: October 2010