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AIX LVM INTRO

sina@

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Agenda

Components of LVM

Mirroring

Striping

Backup LV & VG

How to mirror the rootvg

LVM

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Components of LVMOverview

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Components of LVM

:

Physical volumes

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Components of LVMThe structure of PV

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Components of LVMPVID

1. AIX ODM is used to attach an hdiskx name to PVID of a disk.

2. The PVID is the soft "serial number" of a disk that is created.

3. The PVID can be obtained by issuing:

#chdev -l hdiskX -a pv=yes

#lspv

hdisk0 00c9c7c56ca27a2a rootvg active

hdisk1 00c9c7c5018928b6 rootvg active

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Components of LVMPV Layout

Starting

Sector

Description

0 bootrecord

1 Configuration

2 MWC cache

7 LVM

8 bad block

22 bad block length

64 config backup

70 LVM backup

71 bad block backup

Starting

Sector

Description

120 concurrent config

128 VGDA / VGSA

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Components of LVMVolume Groups

1. VGID

2. VGDA

3. VGSA

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Components of LVMLogical Volumes

1. LVID: logical volume identifier

2. LVCB: logical volume control block

3. LP: LV is made up of LPs.

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Components of LVMFileSystem

inode

JFS Log

log

log

inode

log

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Agenda

Components of LVM

Mirroring

Striping

Backup LV & VG

How to mirror the rootvg

LVM

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MirroringMirror

1. Each logical volume may have two or three mirrored copies

2. Only logical volumes are mirrored

PP2PP1

hdisk0

PP2PP1

hdisk1

PP2PP1

hdisk2

LP1

LP2

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Agenda

Components of LVM

Mirroring

Striping

Backup LV & VG

How to mirror the rootvg

LVM

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StripingStripe

As known as RAID 0, The Striping is a technology that was developed to

achieve I/O performance gain.

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Agenda

Components of LVM

Mirroring

Striping

Backup LV & VG

How to mirror the rootvg

LVM

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Backup LV&VGBackup LV

1. mirror vg / mklvcopy

2. cplv

3. migratepv

4. mksysb

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Backup LV&VGBackup VG

1. mirror vg

2. exportvg

3. alt_disk_copy

4. mksysb

5. savevg

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Agenda

Components of LVM

Mirroring

Striping

Backup LV & VG

How to mirror the rootvg

LVM

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How to mirror the rootvgMirror Rootvg

Why ?

To provide the continuous operation of the AIX operating

system in the event that a disk that is part of the operating

system experiences failure, and there exists an activemirrored copy of the operating system on some other disk.

To provide the ability to boot more than one disk of the

rootvg in the event that another boot disk has failed. In some

cases, the ability to boot from an alternate disk may require

some user intervention.

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How to mirror the rootvgMirror Rootvg

How to do it ?

1.# extendvg rootvg hdiskX

2.# chvg -Qn rootvg

3.# mirrorvg -s rootvg

4.# syncvg -v rootvg

5.# bosboot a

6.# bootlist -m normal hdisk0 hdiskX

7.# bootlist -m normal -o

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Thank You

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