CentOS6.5LVM partition usage details

1. LVM is short for logical disk volume management (LogicalVolumeManager). It is a mechanism for managing disk partitions in Linux, LVM is a logical layer built on hard disks and partitions to improve disk management flexibility in the LVM area. As mentioned above, LVM is a logical layer added between the disk partition and the file system

1. Introduction

LVM is short for Logical volume management (Logical VolumeManager). It is a mechanism for managing disk partitions in Linux. LVM is a Logical layer built on hard disks and partitions, to improve the disk distribution by LVM

The flexibility of zone management. As mentioned above, LVM is a logical layer added between the disk partition and the file system to shield the file system from the underlying disk partition layout and provide an abstract disk volume, create a file system on the disk. A physical volume (physicalvolume) refers to a hardware partition or a device (such as RAID) with the same functions as a disk partition logically. it is the basic storage logical block of LVM, however, compared with basic physical storage media (such as partitions and disks), it contains management parameters related to LVM.

2. Create

[Root @ cn-iss-install-01 mapper] # fdisk-l

[Root @ cn-iss-install-01 mapper] # fdisk/dev/sdb

Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel

Building a new DOS disklabel with disk identifier0x874c7742.

Changes will remain in memory only, until you decide to writethem.

After that, of course, the previous content won't berecoverable.

Warning: invalid flag 0x0000 of partition table 4 will becorrected by w (rite)

WARNING: DOS-compatible mode is deprecated. It's stronglyrecommended

Switch off themode (command 'C') and change display units

Sectors (command 'u ').

Command (m for help): m

Command action

A toggle a bootable flag

B edit bsd disklabel

C toggle the dos compatibility flag

D delete a partition

L list known partition types

M print this menu

N add a new partition

O create a new empty DOS partitiontable

P print the partition table

Q quit without saving changes

S create a new empty Sun disklabel

T change a partition's system id

U change display/entry units

V verify the partition table

W write table to disk and exit

X extra functionality (expertsonly)

Command (m for help): p

Disk/dev/sdb: 96.6 GB, 96636764160 bytes

255 heads, 63 sectors/track, 11748 cylinders

Units = cylinders of 16065*512 = 8225280 bytes

Sector size (logical/physical): 512 bytes/512 bytes

I/O size (minimum/optimal): 512 bytes/512 bytes

Disk identifier: 0x874c7742

Device Boot Start End Blocks Id System

Command (m for help): n

Command action

E extended

P primary partition (1-4)

P

Partition number (1-4): 1

First cylinder (1-11748, default 1 ):

Using default value 1

Last cylinder, + cylinders or + size {K, M, G} (1-11748, default11748): + 80G

Command (m for help): p

Disk/dev/sdb: 96.6 GB, 96636764160 bytes

255 heads, 63 sectors/track, 11748 cylinders

Units = cylinders of 16065*512 = 8225280 bytes

Sector size (logical/physical): 512 bytes/512 bytes

I/O size (minimum/optimal): 512 bytes/512 bytes

Disk identifier: 0x874c7742

Device Boot Start End Blocks Id System

/Dev/sdb1 1 10444 83891398 + 5 Extended

Command (m for help): w

The partition table has been altered!

Calling ioctl () to re-read partition table.

Syncing disks.

[Root @ cn-iss-install-01 mapper] # reboot or

[Root @ cn-iss-install-01 Packages] # partprobe

[Root @ cn-iss-install-01 ~] # Fdisk-l

Disk/dev/sda: 17.2 GB, 17179869184 bytes

64 heads, 32 sectors/track, 16384 cylinders

Units = cylinders of 2048*512 = 1048576 bytes

Sector size (logical/physical): 512 bytes/512 bytes

I/O size (minimum/optimal): 512 bytes/512 bytes

Disk identifier: 0x0005b1c0

Device Boot Start End Blocks Id System

/Dev/sda1*2 251 256000 83 Linux

Partition 1 does not end on cylinder boundary.

/Dev/sda2 252 16384 16520192 8e Linux LVM

Partition 2 does not end on cylinder boundary.

Disk/dev/sdb: 96.6 GB, 96636764160 bytes

255 heads, 63 sectors/track, 11748 cylinders

Units = cylinders of 16065*512 = 8225280 bytes

Sector size (logical/physical): 512 bytes/512 bytes

I/O size (minimum/optimal): 512 bytes/512 bytes

Disk identifier: 0x874c7742

Device Boot Start End Blocks Id System

/Dev/sdb1 1 10444 83891398 + 5 Extended

Disk/dev/mapper/VG00-LV_rootfs: 16.4 GB, 16374562816 bytes

255 heads, 63 sectors/track, 1990 cylinders

Units = cylinders of 16065*512 = 8225280 bytes

Sector size (logical/physical): 512 bytes/512 bytes

I/O size (minimum/optimal): 512 bytes/512 bytes

Disk identifier: 0x00000000

Disk/dev/mapper/VG00-LV_swap: 536 MB, 536870912 bytes

255 heads, 63 sectors/track, 65 cylinders

Units = cylinders of 16065*512 = 8225280 bytes

Sector size (logical/physical): 512 bytes/512 bytes

I/O size (minimum/optimal): 512 bytes/512 bytes

Disk identifier: 0x00000000

[Root @ cn-iss-install-01 ~] #

[Root @ cn-iss-install-01 Packages] # pvcreate/dev/sdb1

Writing physical volume data to disk "/dev/sdb1"

Physical volume "/dev/sdb1" successfully created

[Root @ cn-iss-install-01 Packages] #

[Root @ cn-iss-install-01 Packages] # vgcreate vg03/dev/sdb1

Volume group "vg03" successfully created

[Root @ cn-iss-install-01 Packages] # lvcreate-L 83G-n vgdatavg03

[Root @ cn-iss-install-01 Packages] # mke2fs/dev/vg03/vgdata

Mke2fs 1.41.12 (17-May-2010)

Filesystem label =

OS type: Linux

Block size = 4096 (log = 2)

Fragment size = 4096 (log = 2)

Stride = 0 blocks, Stripe width = 0 blocks

5439488 inodes, 21757952 blocks

1087897 blocks (5.00%) reserved for the super user

First data block = 0

Maximum filesystem blocks = 4294967296

664 block groups

32768 blocks per group, 32768 fragments per group

8192 inodes per group

Superblock backups stored on blocks:

32768,983 04, 163840,229376, 294912,819 200, 884736,160 5632, 2654208,

4096000,796 20480000

Writing inode tables: done

Writing superblocks and filesystem accounting information:

Done

This filesystem will be automatically checked every 23 mountsor

180 days, whichever comes first. Use tune2fs-c or-I tooverride.

[Root @ cn-iss-install-01 Packages] #

[Root @ cn-iss-install-01 Packages] #

[Root @ cn-iss-install-01 Packages] # mkf

Mkfifo mkfs. cramfs mkfs. ext3 mkfs. ext4dev

Mkfs. ext2 mkfs. ext4

[Root @ cn-iss-install-01 Packages] # mkfs. ext4/dev/vg03/vgdata

Mke2fs 1.41.12 (17-May-2010)

Filesystem label =

OS type: Linux

Block size = 4096 (log = 2)

Fragment size = 4096 (log = 2)

Stride = 0 blocks, Stripe width = 0 blocks

5439488 inodes, 21757952 blocks

1087897 blocks (5.00%) reserved for the super user

First data block = 0

Maximum filesystem blocks = 4294967296

664 block groups

32768 blocks per group, 32768 fragments per group

8192 inodes per group

Superblock backups stored on blocks:

32768,983 04, 163840,229376, 294912,819 200, 884736,160 5632, 2654208,

4096000,796 20480000

Writing inode tables: done

Creating journal (32768 blocks): done

Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 37 mountsor

180 days, whichever comes first. Use tune2fs-c or-I tooverride.

[Root @ cn-iss-install-01 Packages] #

[Root @ cn-iss-install-01 spool] # mount/dev/vg03/vgdata/var/spool/repo/

[Root @ cn-iss-install-01 spool] # cd repo/

[Root @ cn-iss-install-01 repo] # ls

Lost + found

[Root @ cn-iss-install-01 repo] # pwd

/Var/spool/repo

[Root @ cn-iss-install-01 repo] #

3. common check commands:

[Root @ cn-iss-install-01/] # pvdisplay

[Root @ cn-iss-install-01/] # vgdisplay

[Root @ cn-iss-install-01/] # lvdisplay

[Root @ cn-iss-install-01/] # pvcreate

Please enter a physical volume path

Run 'pvcreate -- help' for more information.

[Root @ cn-iss-install-01/] # vgcreate

Please provide volume group name and physical volumes

Run 'vgcreate -- help' for more information.

[Root @ cn-iss-install-01/] # lvcreate

Please provide a volume group name

Run 'lvcreate -- help' for more information.

[Root @ cn-iss-install-01/] # vgextend

Please enter volume group name and physical volume (s)

Run 'vgextend -- help' for more information.

[Root @ cn-iss-install-01/] # lvextend

Please specify either size or extents but not both.

Run 'lvextend -- help' for more information.

[Root @ cn-iss-install-01/] #