Veritas VxVM Volume Manager Août09

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Veritas VxVM Volume Manager

Petit tutorial sur Veritas VxVM, gestion du raid de VERITAS.

Veritas Volume Manager

1. Volume Manager
Objects

1.1 Disks

1.2 Disk groups

1.3 Volume Manager disks

1.4 Subdisks

1.5 Plexes

1.6 Volumes

1.7 Volume
Manger Objects & their Relationship

2. Volume
Manager Configuration ( options menu)

2.1 Add or initialize one or
more disks

2.2
Encapsulate one or more disks

2.3
Remove a disk

2.4
Remove a disk for replacement

2.5
Replace a failed or removed
disk

2.6
Mirror volumes on a disk

2.7
Move volumes from a disk

2.8
Enable access to
(import) a disk group

2.9
Remove access to
(deport) a disk group

2.10
Enable (online) a disk device

2.11
Disable (offline) a disk device

2.12
Mark a disk as a spare
for a disk group

2.13
Turn off the spare flag on a
disk

About Veritas volume manager :

Veritas Volume Manager is a software product from veritas Inc. and it is
used to manage disk storage .

The main features of volume manager are following :

1. Allows creation of logical volumes spanning over multiple disks.
This overcomes the physical limit of the disk .

2. Provides high availability storage solutions through RAID
,Mirroring of disks .

3. Provides fail over features by providing transferable disk group
ownership between systems.

4. Dynamic reconfiguration of disk storage in an online system state.
what is veritas volume manager .

The following article describes the volume manager
objects and configuration of these objects using a text menu based
utility called vxdiskadm .

1.0 Volume Manager
Objects

Disks

Disks are referred in volume
manager by two terms – device name and disk name . The device name
specifies controller , target id and slice of the disk . Disk name is the common
name given to the device name as an easy to remember name .

For example device name
c2t3dos2 represents controller number 2 , target id 3 , disk group 0
and slice 2 and disk01 may be its disk name . While device name is system dependent
based on controller and disk id the disk
name is user defined .

Disk groups :

  • A disk group is a collection of volume manager disks grouped together to hold
    the data . All the configuration changes made to a disk group are applied
    to the disks in that disk group only.

  • Volume Manager objects cannot span disk groups i.e. all the operations
    on a
    particular disk group remains confined to that particular group .

  • Disk groups enable high availability as these can be
    shared by two or more hosts but can be accessed by only one host at a time.
    In two hosts and a shared storage situation one host can take over the ownership of the
    disk groups and
    drives in case other host fails.

Volume Manager disks

  • Adding physical disks to the volume manager results in
    creation of public and private region in the disk by the volume
    manager .The public region is the disk space available for volume space and
    the private region stores the configuration information.

  • A Volume Manager disks are created from the public region of a
    physical disk that is under Volume Manager control. Each volume manager disk
    corresponds to one physical disk.

  • A volume manager disk is given a disk media name when it is added to a disk
    group which can be default or unique user defined..

  • Once a volume manager disk is assigned a disk media name, the disk is no longer
    referred to by its physical address of c#t#d#.
    The physical address of c#t#d#
    becomes known as the disk access record.

Subdisks

  • A subdisk is a subsection of a disk's public region and is the
    smallest unit of storage in Volume Manager.

  • A subdisk is defined by an offset and a length in sectors on a
    volume manager disk.

  • A volume manager disk can contain multiple subdisks but subdisks cannot
    overlap or share the same portions of a volume manager disk.

  • volume manager disk space that is not reserved or that is not part of a subdisk is
    free space. You can use free space to create new subdisks.

A subdisk is similar to a partition but with following differences :

  • The maximum number of partitions to a disk is eight.

  • There is no theoretical limit to number of subdisks that can be attached
    to a single plex, but
    it has been limited to a default value of 4096. If required, this default
    can be changed, using the vol_subdisk_num
    tunable parameter.

Plexes

  • A plex is a
    structured or ordered collection of subdisks that represents one copy of
    the data in a volume. A plex
    consists of one or more subdisks located on one or more physical disks.

  • A plex
    is also
    called a mirror. The terms
    plex and mirror
    can be used interchangeably, even though a plex
    is only one copy of the data. The terms
    "mirrored" or "mirroring" imply two or more copies of
    data.

  • The length of a plex
    is determined by the last block that can be read or written on the last
    subdisk in the plex.

  • The default naming convention for plexes in a volume is volumename-##.
    The default plex
    name consists of the volume name, a hyphen, and a two-digit number

Volumes

  • A volume is composed of one or more plexes not restricted by the
    physical size of the disk.

  • A volume can span across multiple disks.

  • Volume Manager uses the default naming convention vol##
    for volumes, where ## represents a two-digit number but can be user defined
    as per requirement.

Volume
Manager Objects and Their Relationship

2.0 Volume Manager Configuration

Volume configuration consists of adding two or
more disks to form disk group and create volume/s from this disk group. File system
can be created on these volumes or these can be accessed as raw devices for some database
applications. First step in volume manager configuration consists of adding and initializing
disks under volume manager which creates a public
region which is bulk of disk space available for volume space .Private region which
is generally of a few megabytes stores the disk configuration information .

Most of the volume manager operation related to disks
& volume can be performed by a character based menu utility call vxdiskadm

Following paragraphs describes the use of vxddiskadm to configure and manage
volume manager.

#vxdiskadm

Typing vxdiskadm brings up a menu based utility (text) . The options ,
their explanation and screen shots are given below .Most of the options need a
disk name , device name or disk group name and you can have this information by
typing list in the vxdiskadm menu .The list menu option is used to display a
list of disks attached to your system. This also lists removed or failed disks. Most
useful to get a quick view of all disks or list details of a single disk – its name
, volume association and status.

A disk needs to be formatted in
order to be included in volume manager . volume manager will report unformatted disk as invalid and a
will only recognize after formatting

By default all the available disks in the system are considered for inclusion
as volume manager disk however to exclude certain disks, list the
names of the disks to be excluded in the file /etc/vx/disks.exclude before the
initialization or encapsulation. Similarly, you can exclude all disks on specific
controllers from initialization or encapsulation by listing those controllers in the file
/etc/vx/cntrls.exclude.

? & ?? options provide help about the menu item and menu system.

#vxdiskadm

Volume
Manager Support Operations

Menu: VolumeManager/Disk

1 Add or initialize one or more disks

2 Encapsulate one or more disks

3 Remove a disk

4 Remove a disk for replacement

5 Replace a failed or removed disk

6 Mirror volumes on a disk

7 Move volumes from a disk

8 Enable access to (import) a disk group

9 Remove access to (deport) a disk group

10 Enable (online) a disk device

11 Disable (offline) a disk device

12 Mark a disk as a spare for a disk group

13 Turn off the spare flag on a disk

list List disk information

? Display help about
menu

?? Display help about the menuing system

q Exit from menus

Select an operation to perform

2.1 Add or initialize one or more disks

The formatted disks can be added or initialized with volume manager
.
Disk groups needs to be given for making a new group or adding disks in
existing group. Default disk group is rootdg and if none is specified
the disks are added to volume manager and are kept as hot spares which can be used in
place of a failed disk.

Select 1 (Add or initialize one or more disks)
from the vxdiskadm main menu.

Add or initialize disks

Menu: VolumeManager/Disk/AddDisks

Use this operation to add one or more disks to a disk group. You
can add the selected disks to an existing disk group or to a new
disk group that will be created as a part of the operation. The
selected disks may also be added to a disk group as spares. The
selected disks may also be initialized without adding them to a disk
group leaving the disks available for use as replacement disks.

More than one disk or pattern may be entered at the prompt. Here are some disk
selection examples:

all:
all
disks

c3 c4t2: all disks on both controller 3
and controller 4,target 2

c3t4d0: a single disk

Select disk devices to add:

[,all,list,q,?]list

can be a single or more disks and/or controllers. If
consists of multiple items, those items must be separated by white space.

list at the prompt displays a list of the disks available to the system, followed by a prompt at which you
should type the device name of the disk to be added:

DEVICE
DISK
GROUP STATUS

c0t0d0
disk01 rootdg
online

c0t1d0
disk02 rootdg
online

c0t2d0
disk03 rootdg
online

c0t3d0


online

c1t0d0
disk10 rootdg
online

c1t0d1


error

.

.

.

c3t0d0


error

c3t1d0
disk33 rootdg
online

c3t2d0
disk34 rootdg
online

c3t3d0
disk35 rootdg
online

Select disk devices to add:

[,all,list,q,?] c1t0d1

All disks attached to the system are recognized by
the Volume Manager
and displayed here.. Error status indicates disks not recognized by volume manager
as part of volume manager and can be used to add in the volume manager .. Disks with a name , group and online status are
present in volume manager in a valid volume manager disk group .One or more disks separated
by space can be
selected for adding into volume manager.


Here is the disk selected. Output format: [Device_Name]

c1t2d0

Continue operation? [y,n,q,?] (default: y) y


You can
choose to add this disk to an existing disk group, a

new disk group, or leave the disk available for use
by future

add or replacement operations. To create a
new disk group, select a disk group name that does not yet exist. To
leave the disk

available for future use, specify a disk group name
of "none".

Which disk group [,none,list,q,?] (default:
rootdg)

Use a default disk name for the disk? [y,n,q,?] (default: y)

Add disk as a spare disk for
rootdg? [y,n,q,?] (default: n)

n

The
selected disks will be added to the disk group rootdg with

default disk names.

c1t2d0

Continue with operation? [y,n,q,?] (default: y) y

The following disk device has a valid VTOC, but
does not appear to have

been initialized for the Volume Manager. If
there is data on the disk

that should NOT be destroyed you should encapsulate
the existing disk

partitions as volumes instead of adding the disk as
a new disk.

Output format: [Device_Name]

c1t2d0

Encapsulate this device? [y,n,q,?] (default: y) n

c1t2d0

Instead of encapsulating, initialize? [y,n,q,?] (default: n)
y

Initializing device c1t2d0.

Adding disk device c1t2d0 to disk group rootdg
with disk

name disk39.

Add or initialize other disks? [y,n,q,?] (default:
n)

2.2 Encapsulate one or more disks

This is used to bring the disk under volume manager , which are
already present in the system with data but without volume manager . Data on these disks are
not disturbed and if these disks meets certain volume manager requirements these are added
under volume manager.

System
needs rebooting if encapsulation is used for disk with mounted
filesystem or running applications . Also the old device names
needs to
be changed in applications/scripts to reflect the new volume name.

vfstab information is updated automatically but
it is worthwhile to check vfstab if changes are proper as any discrepancy in vfstab
may cause system boot failure on next reboot.

Encapsulation preserves any existing data on the disk when
the disk is placed under volume manager control. To reduce the

chance of encapsulation failure, make sure that the disk
meets the following requirements:-

  • It has a small amount of free space (at the beginning or end
    of the disk) that does not belong to any partition

  • It has two free partitions

  • It has an s2 slice that represents the whole disk

One of the most common application is encapsulation of
root disk to bring it under volume manager and then mirror it to have an
alternate boot disk .

The EEPROM variable use-nvramrc? must be set to true and an
alternate boot disk alias name needs to be defined to access the second boot
disk by an alternate alias name in case primary disk fails.

ok>eeprom use-nvramrc?=true

Procedure for encapsulating a disk for volume manager use is
as follows:

Select menu item 2 (Encapsulate
one or more disks) from the vxdiskadm main menu and follow the prompts
:-

Encapsulate one or more disks

Menu: VolumeManager/Disk/Encapsulate

Use this operation to convert one or more disks to use the
Volume Manager.

This adds the disks to a disk group and replaces existing

partitions

with volumes. Disk encapsulation requires a reboot
for the

changes to take effect.

More than one disk or pattern may be entered at the
prompt. Here

are some disk selection examples:

all: all
disks

c3 c4t2: all disks on
both controller 3 and controller 4, target 2

c3t4d0: a single
disk

Select disk devices to encapsulate:

[,all,list,q,?] c2t5d0

can be a single
disk, or a series of disks and/or controllers (with optional targets). If
consists of multiple items, those items must be separated by white space.

 

 


Here is the disk selected. Output format: [Device_Name]

c2t5d0

Continue operation? [y,n,q,?] (default: y) y


You can choose to add this disk to an existing disk group or
to

a new disk group. To create a new disk group,
select a disk group name that does not yet exist.

Which disk group [,list,q,?] (default:
rootdg)

Use a default disk name for the disk? [y,n,q,?]
(default: y)

The selected disks will be encapsulated and
added to the rootdg

disk group with default disk names.

c2t5d0

Continue with operation? [y,n,q,?] (default: y) y

The following disk has been selected for encapsulation. Output format:

[Device_Name]

c2t5d0

Continue with encapsulation? [y,n,q,?] (default: y)
y


The disk device c2t5d0 will be encapsulated and added
to the disk

group rootdg with the disk name
disk01.

The c2t5d0 disk has been configured for
encapsulation.

The first stage of encapsulation has completed
successfully. You

should now reboot your system at the earliest
possible opportunity.

The encapsulation will require two or three
reboots which will happen automatically after the next reboot. To
reboot execute the command:

shutdown -g0 -y -i6

This will update the /etc/vfstab file so that
volume devices are

used to mount the file systems on this disk
device. You will need to update any other references such as backup
scripts, databases,

or manually created swap devices.

Encapsulate other disks?
[y,n,q,?] (default: n)
n

The disk device c2t5d0 will be encapsulated and added to the
disk group rootdg with the disk name disk01.

The encapsulation operation failed with the
following error:

It is not possible to encapsulate c2t5d0, for the
following reason:

Unsupported disk layout.>

Hit RETURN to continue.

Encapsulation may fail if there is not enough free space available on
the disk to accommodate volume manager. If this happens, the procedure above will end
abruptly with an error message as above .

2.3 Remove a disk

This option is used to remove a disk from a
disk group provided there is no active volume using this disk .. If there are
some volumes using the disk the those have to be either moved to some other disk or
removed if they are no longer needed.

However since a diskgroup must have at least one
disk you can not remove all the disks from a disk group . To remove all disks from a
diskgroup you have to disable the volume group with the exception of rootdg disk
group which can not be disabled .

Select menu item 3 (Remove a disk) from the

vxdiskadm main menu.

Remove a disk

Menu: VolumeManager/Disk/RemoveDisk

Use this operation to remove a disk from a disk group. This

operation takes, as input, a disk name. This is the same
name

that you gave to the disk when you added the disk to the
disk

group.

Enter disk name [,list,q,?] disk01

Requested operation is to
remove disk disk01 from group rootdg.

Continue with operation? [y,n,q,?] (default:
y)

Removal of disk disk01 is
complete.

Remove another disk? [y,n,q,?] (default: n)

2.4 Remove a disk for replacement

This option is used for removing the disk
but retaining the name of the disk so that it can be used by the newly replaced disk . The
replacement disk can be a newly added disk or already available disk in the other disk
groups

Select menu item 4 (Remove a
disk for replacement) from the
vxdiskadm main menu.

Remove a disk for replacement

Menu: VolumeManager/Disk/RemoveForReplace

Use this menu operation to remove a physical disk from a
disk

group, while retaining the disk name. This changes the
state

for the disk name to a removed disk. If there are any

initialized disks that are not part of a disk group, you will
be

given the option of using one of these disks as a
replacement.

Enter disk name [,list,q,?] disk02

Additional screens display if there are volumes
associated with the disk you want to remove. You have to decide if data is
needed or not needed and answer the prompts as asked .

The following devices are available as replacements:

c1t1d0

You can choose one of these disks now, to replace disk02.

Select "none" if you do not wish to select a replacement
disk.

Choose a device, or select "none"

[,none,q,?] (default: c1t1d0)

Requested operation is to
remove disk disk02 from group rootdg.

The removed disk will be replaced with disk device
c1t1d0.

Continue with operation? [y,n,q,?] (default: y)

Removal of disk disk02
completed successfully.

Proceeding to replace disk02 with device c1t1d0.


Disk replacement completed successfully.


Remove another disk? [y,n,q,?]
(default: n)

 

2.5 Replace a failed or removed disk

This option is used to replace a failed or
removed disk . The new disk can be initialized or non initialized as this option
does initialization .

Select menu item 5 (Replace a
failed or removed disk) from the
vxdiskadm main menu.

Replace a failed or removed disk

Menu: VolumeManager/Disk/ReplaceDisk

Use this menu operation to specify a replacement disk for a
disk

that you removed with the "Remove a disk for replacement"
menu

operation, or that failed during use. You will be prompted
for

a disk name to replace and a disk device to use as a
replacement.

You can choose an uninitialized disk, in which case the disk
will

be initialized, or you can choose a disk that you have
already

initialized using the Add or initialize a disk menu
operation.

Select a removed or failed disk [,list,q,?] disk02

The following devices are
available as replacements:

c1t0d0s2 c1t1d0s2

You can choose one of these disks to replace
disk02.

Choose "none" to initialize another disk to replace
disk02.

Choose a device, or select "none"

[,none,q,?] (default:
c1t0d0s2)

The requested operation is to use the initialized device
c1t0d0s2

to replace the removed or failed disk disk02 in disk
group rootdg.

Continue with operation? [y,n,q,?] (default: y)


Replacement of disk disk02 in group rootdg with disk
device

c1t0d0s2 completed successfully.

2.6 Mirror volumes on a disk

volumes can be mirrored to another disk with
available space however it can not be used to mirror existing mirrors or mirrors spanning
more than one sub disk .

To mirror volumes on a disk, make sure that the
target disk has an equal or greater amount of space as the originating disk and then do
the following

Select menu item 6 (Mirror
volumes on a disk) from the vxdiskadm main menu.

Mirror volumes on a disk

Menu: VolumeManager/Disk/Mirror

This operation can be used to mirror volumes on a disk.
These

volumes can be mirrored onto another disk or onto any

available disk space. Volumes will not be mirrored if they
are

already mirrored. Also, volumes that are comprised of more
than

one subdisk will not be mirrored.

Mirroring volumes from the boot disk will produce a disk that
can

be used as an alternate boot disk.

Enter disk name [,list,q,?] disk02

You can choose to mirror
volumes from disk disk02 onto any

available disk space, or you can choose to mirror onto a
specific

disk. To mirror to a specific disk, select the name of that
disk.

To mirror to any available disk space, select
"any".

Enter destination disk [,list,q,?] (default: any) disk01

Note – Be sure to always specify the
destination disk when you are creating an alternate root disk. Otherwise, the
volume manager will select space available in the disk group which might
span disk and will result in boot failure from this disk.

2.7 Move volumes from a disk

This option is used in case the disk is to be replaced or
removed and has active volumes on the disk. . Also volumes can be moved to different disk
groups for better space , performance etc.

Select menu item 7 (Move volumes from a disk) from the from the from the from the vxdiskadm
main menu.

Move volumes from a disk

Menu: VolumeManager/Disk/Evacuate

Use this menu operation to move any volumes that are using
a

disk onto other disks. Use this menu immediately prior to

removing a disk, either permanently or for replacement. You
can

specify a list of disks to move volumes onto, or you can move
the

volumes to any available disk space in the same disk group.

NOTE: Simply moving volumes off of a disk, without also
removing

the disk, does not prevent volumes
from being moved onto

the disk by future operations. For
example, using two

consecutive move operations may
move volumes from the

second disk to the
first.

Enter disk name [,list,q,?] disk01

You can now specify a list of disks to move onto.
Specify a list

of disk media names (e.g., disk01) all on one line separated
by

blanks. If you do not enter any disk media names, then
the

volumes will be moved to any available space in the disk
group.

Requested operation is to
move all volumes from disk disk01 in

group rootdg.

NOTE: This operation can take a long time to
complete.

Continue with operation? [y,n,q,?] (default: y)

Move volume vol3

Move volume vol3-bk00 …

Evacuation of disk disk01 is complete.

Move volumes from
another disk? [y,n,q,?] (default: n)

 

2.8 Enable access to (import) a disk group

Used in enabling ownership of the other system to
a disk group which has been deported by the other system. Used in failover
configurations where the ownership of a shared disk/disk group is transferred to the other
system in case of failure of current system.

Select menu item 8(Enable access to (import) a disk group)

from the
vxdiskadm main menu.

Enable access to (import) a disk group

Menu: VolumeManager/Disk/EnableDiskGroup

Use this operation to enable access to a disk group. This can
be

used as the final part of moving a disk group from one system
to

another. The first part of moving a disk group is to use
the

"Remove access to (deport) a disk group" operation on
the

original host.

A disk group can be imported from another host that failed
without

first deporting the disk group. Be sure that all disks in the
disk

group are moved between hosts.

If two hosts share a SCSI bus, be very careful to ensure that
the

other host really has failed or has deported the disk group.
If

two active hosts import a disk group at the same time, the
disk

group will be corrupted and will become unusable.

Select disk group to import [,list,q,?] (default:
list)

newdg

The import of newdg was successful.

Select another disk
group? [y,n,q,?] (default: n)

2.9 Disable access to (deport) a disk group

Disk group is deported if disks
groups ownership needs to be transferred to another system or all the disks in
a disk groups needs to be freed from group. Disks in a disk groups to be deported should
not be active.

Select menu item 9 (Remove access to (deport) a disk group)
from the
vxdiskadm main menu.


Remove access to (deport) a disk group

Menu: VolumeManager/Disk/DeportDiskGroup

Use this menu operation to remove access to a disk group that
is

currently enabled (imported) by this system. Deport a disk

group if you intend to move the disks in a disk group to
another

system. Also, deport a disk group if you want to use all of
the

disks remaining in a disk group for some new purpose.

You will be prompted for the name of a disk group. You will
also

be asked if the disks should be disabled (offlined). For

removable disk devices on some systems, it is important to

disable all access to the disk before removing the disk.

Enter name of disk group [,list,q,?] (default: list) newdg

The requested operation is to
disable access to the removable

disk group named newdg. This disk group is stored on
the

following disks:

newdg01 on device
c1t1d0s2

You can choose to disable access to (also known as
"offline")

these disks. This may be necessary to prevent errors
if

you actually remove any of the disks from the
system.

Disable (offline) the indicated disks? [y,n,q,?] (default:
n)

Continue with operation? [y,n,q,?] (default: y)

Removal of disk group newdg was successful.

Disable another disk group? [y,n,q,?] (default: n)

2.10 Enable (online) a disk device

Disks which are turned offline by volume manager
, or which are to be imported can be enabled by this option. This operation causes disks to be scanned and find out the
disk belonging to a disk group.

Select menu item 10 (Enable
(online) a disk device
) from the
vxdiskadm main menu.

Enable (online) a disk device

Menu: VolumeManager/Disk/OnlineDisk

Use this operation to enable access to a disk that was
disabled

with the "Disable (offline) a disk device"
operation.

You can also use this operation to re-scan a disk that may
have

been changed outside of the Volume Manager. For example, if a
disk

is shared between two systems, the Volume Manager running on
the

other system may have changed the disk. If so, you can use
this

operation to re-scan the disk.

NOTE: Many vxdiskadm operations re-scan disks without user

intervention. This will eliminate
most needs to online a

disk directly, except when the disk
is directly offlined.

Select a disk device to enable [

,list,q,?] c1t1d0

Enable another device? [y,n,q,?] (default: n)

2.11 Disable (offline) a disk device

This
option disables all access to a disk which is not part of
any disk group . This is used to remove disk from volume group. Some
systems do not support disks that
can be removed from a system during normal operation. On such systems,
the offline
operation is not very useful.

Select menu item 11 (Disable
(offline) a disk device)

from the

vxdiskadm
main menu.

Disable (offline) a disk device

Menu: VolumeManager/Disk/OfflineDisk

Use this menu operation to disable all access to a disk
device

by the Volume Manager. This operation can be applied only
to

disks that are not currently in a disk group. Use this
operation

if you intend to remove a disk from a system without
rebooting.

NOTE: Many systems do not support disks that can be removed
from

a system during normal operation.
On such systems, the

offline operation is seldom
useful.

Select a disk device to disable [

,list,q,?] c1t1d0

Disable another device? [y,n,q,?]
(default: n)

2.12 Mark a disk as a
spare for a disk group

This is used to reserve the disk as an automatic
replacement disk ( hot-relocation) in case of another disk in the disk
group fails. Hot-relocation relocates redundant subdisks to
other disks and restores the affected volume manager objects and data. If a disk
has already been designated as a spare in the disk group, the subdisks from
the failed disk are relocated to the spare disk. Otherwise, any suitable
free space in the disk group is used.

Select menu item 12 (Mark a
disk as a spare for a disk group) from the
vxdiskadm main menu.

Mark a disk as a spare for a disk group

Menu: VolumeManager/Disk/MarkSpareDisk

Use this operation to mark a disk as a spare for a disk
group.

This operation takes, as input, a disk name. This is the
same name

that you gave to the disk when you added the disk to the
disk group.

Enter disk name [,list,q,?] disk01

Marking of disk01 in rootdg as a spare disk is complete.

Mark another disk as a spare? [y,n,q,?] (default:
n)

Any VM disk in this disk group can now use this disk as a spare in the
event of a failure. If a disk fails, hot-relocation should automatically occur
.The failed disk needs to be replaced.

2.13 Turn off the spare flag
on a disk

This is used to remove a VM Disk From the Hot-Relocation
Pool & free hot-relocation spare disks for use as regular volume manager
disks While a disk is designated as a spare, the space on that disk is
not used as free space for the creation of volume manager objects within its disk
group and this option makes this space available.

Select menu item 13 (Turn off
the spare flag on a disk) from the
vxdiskadm main menu.

Turn off the spare flag on a disk

Menu: VolumeManager/Disk/UnmarkSpareDisk

Use this operation to turn off the spare flag on a
disk.

This operation takes, as input, a disk name. This is the
same

name that you gave to the disk when you added the disk to
the

disk group.

Enter disk name [,list,q,?] disk01


Disk disk01 in rootdg no longer marked as a spare disk.


Turn-off spare flag on another disk? [y,n,q,?] (default: n)

After using the vxdiskadm for configuring disks and diskgroups
next step is to configure volumes and then use them for storage operations .
The second part of this article discusses this aspect of volume manager