LVM Logical Volume Manager-example of increasing LV capacity

Steps:

(1) add a new 8e systemID partition;

(2) use the pvcreate command to construct the PV;

(3) use the vgextend command to add PV to vg_1;

(4) Use the lvresize command to add the PE in the newly added PV to lv_1;

(5) Use the resize2fs command to expand the LV capacity to the entire file system;

 
(1) add a new 8e systemID partition. Since the previous four primary partitions are created, if you want to create another partition, delete/dev/sdb4, create an extended partition and add the 8e systemID partition under the extended partition. The steps are as follows:

[Root @ centos6 ~] # Df-h # Check the lvm mounting status
Filesystem Size Used Avail Use % Mounted on
/Dev/sda3 16G 1.5G 14G 11%/
Tmpfs 112 M 0 112 M 0%/dev/shm
/Dev/sda1 194 M 29 M 155 M 16%/boot
/Dev/mapper/vg_1-lv_1 20G 172 M 19G 1%/mnt/lvm
[Root @ centos6 ~] # Umount/mnt/lvm/# Uninstall lvm
[Root @ centos6 ~] # Df-h
Filesystem Size Used Avail Use % Mounted on
/Dev/sda3 16G 1.5G 14G 11%/
Tmpfs 112 M 0 112 M 0%/dev/shm
/Dev/sda1 194 M 29 M 155 M 16%/boot
[Root @ centos6 ~] # Lvremove/dev/vg_1/lv_1 # delete lv_1
Do you really want to remove active logical volume lv_1? [Y/n]: y
Logical volume "lv_1" successfully removed
[Root @ centos6 ~] # Lvs
[Root @ centos6 ~] # Vgreduce vg_1/dev/sdb4 # Remove/dev/sdb4 from vg_1
Removed "/dev/sdb4" from volume group "vg_1"
[Root @ centos6 ~] # Pvremove/dev/sdb4 # Remove/dev/sdb4 from pv
Labels on physical volume "/dev/sdb4" successfully wiped
[Root @ centos6 ~] # Pvs # View pv
Pv vg Fmt Attr PSize PFree
/Dev/sdb1 vg_1 lvm2 a -- 5.00g 5.00g
/Dev/sdb2 vg_1 lvm2 a -- 5.00g 5.00g
/Dev/sdb3 vg_1 lvm2 a -- 5.00g 5.00g
[Root @ centos6 ~] # Fdisk/dev/sdb # partition into/dev/sdb disk
WARNING: DOS-compatible mode is deprecated. It's stronugly recommended
Switch off the mode (command 'C') and change display units
Sectors (command 'u ').
Command (m for help): p
Disk/dev/sdb: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x60710230
Device Boot Start End Blocks Id System
/Dev/sdb1 1 654 5253223 + 8e Linux LVM
/Dev/sdb2 655 1308 5253255 8e Linux LVM
/Dev/sdb3 1309 1962 5253255 8e Linux LVM
/Dev/sdb4 1963 2616 5253255 8e Linux LVM
Command (m for help): d # Delete/dev/sdb4 partition
Partition number (1-4): 4
Command (m for help): p
Disk/dev/sdb: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x60710230
Device Boot Start End Blocks Id System
/Dev/sdb1 1 654 5253223 + 8e Linux LVM
/Dev/sdb2 655 1308 5253255 8e Linux LVM
/Dev/sdb3 1309 1962 5253255 8e Linux LVM
Command (m for help): n
Command action
E extended
P primary partition (1-4)
E
Selected partition 4 # create an extended partition
First cylinder (1963-10443, default 1963 ):
Using default value 1963
Last cylinder, + cylinders or + size {K, M, G} (1963-10443, default 10443): + 10G
Command (m for help): p
Disk/dev/sdb: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x60710230
Device Boot Start End Blocks Id System
/Dev/sdb1 1 654 5253223 + 8e Linux LVM
/Dev/sdb2 655 1308 5253255 8e Linux LVM
/Dev/sdb3 1309 1962 5253255 8e Linux LVM
/Dev/sdb4 1963 3268 10490445 5 Extended
Command (m for help): n # Create a new partition
First cylinder (1963-3268, default 1963 ):
Using default value 1963
Last cylinder, + cylinders or + size {K, M, G} (1963-3268, default 3268): + 5G
Command (m for help): p
Disk/dev/sdb: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x60710230
Device Boot Start End Blocks Id System
/Dev/sdb1 1 654 5253223 + 8e Linux LVM
/Dev/sdb2 655 1308 5253255 8e Linux LVM
/Dev/sdb3 1309 1962 5253255 8e Linux LVM
/Dev/sdb4 1963 3268 10490445 5 Extended
/Dev/sdb5 1963 2616 5253223 + 83 Linux
Command (m for help): t
Partition number (1-5): 5
Hex code (type L to list codes): 8e # Change the systemID of the/dev/sdb5 partition to 8e.
Changed system type of partition 5 to 8e (Linux LVM)
Command (m for help): p
Disk/dev/sdb: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x60710230
Device Boot Start End Blocks Id System
/Dev/sdb1 1 654 5253223 + 8e Linux LVM
/Dev/sdb2 655 1308 5253255 8e Linux LVM
/Dev/sdb3 1309 1962 5253255 8e Linux LVM
/Dev/sdb4 1963 3268 10490445 5 Extended
/Dev/sdb5 1963 2616 5253223 + 8e Linux LVM
Command (m for help): w
The partition table has been altered!
Calling ioctl () to re-read partition table.
Syncing disks.
[Root @ centos6 ~] # Partprobe

Create a lv and mount it;

[Root @ centos6 ~] # Lvcreate-L 15G-n lv_1 vg_1
Logical volume "lv_1" created
[Root @ centos6 ~] # Lvs
Lv vg Attr LSize Pool Origin Data % Move Log Cpy % Sync Convert
Lv_1 vg_1-wi-a ----- 15.00g
[Root @ centos6 ~] # Mkfs-t ext4/dev/vg_1/lv_1
[Root @ centos6 ~] # Mount/dev/vg_1/lv_1/mnt/lvm
[Root @ centos6 ~] # Df-h
Filesystem Size Used Avail Use % Mounted on
/Dev/sda3 16G 1.5G 14G 11%/
Tmpfs 112 M 0 112 M 0%/dev/shm
/Dev/sda1 194 M 29 M 155 M 16%/boot
/Dev/mapper/vg_1-lv_1 15G 166 M 14G 2%/mnt/lvm

(2) create a new PV;

[Root @ centos6 ~] # Pvcreate/dev/sdb5
Physical volume "/dev/sdb5" successfully created
[Root @ centos6 ~] # Pvs
Pv vg Fmt Attr PSize PFree
/Dev/sdb1 vg_1 lvm2 a -- 5.00g 0
/Dev/sdb2 vg_1 lvm2 a -- 5.00g 0
/Dev/sdb3 vg_1 lvm2 a -- 5.00g 0
/Dev/sdb5 lvm2 a -- 5.01g 5.01g

(3) use the vgextend command to add PV to vg_1;

[Root @ centos6 ~] # Vgextend vg_1/dev/sdb5
Volume group "vg_1" successfully extended
[Root @ centos6 ~] # Vgs
VG # PV # LV # SN Attr VSize VFree
Vg_1 4 1 0 wz -- n-20.00g 5.00g
[Root @ centos6 ~] # Vgdisplay
--- Volume group ---
VG Name vg_1
System ID
Format lvm2
Metadata Areas 4
Metadata Sequence No 15
VG Access read/write
VG Status resizable
Max lv 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 4
Act PV 4
VG Size 20.00 GiB
PE Size 16.00 MiB
Total PE 1280
Alloc PE/Size 960/15 .00 GiB
Free PE/Size 320/5 .00 GiB # remaining 320 PES with a capacity of 5 GB
Vg uuid NpO8m2-s4rx-WOIA-SbCt-yqQV-MU1w-wru4cS

(4) Use the lvresize command to add the PE in the newly added PV to lv_1;

[Root @ centos6 ~] # Lvresize-l + 320/dev/vg_1/lv_1
Extending logical volume lv_1 to 20.00 GiB
Logical volume lv_1 successfully resized
[Root @ centos6 ~] # Lvdisplay
--- Logical volume ---
LV Path/dev/vg_1/lv_1
LV Name lv_1
VG Name vg_1
Lvuuid n2bChT-rimu-eRDs-5onU-mgUF-ukuh-NqO7me
LV Write Access read/write
LV Creation host, time centos6.5, 19:04:37 + 0800
LV Status available
# Open 1
LV Size 20.00 GiB # check that the LV capacity has changed to 20 GB
Current LE 1280
Segments 4
Allocation inherit
Read ahead sectors auto
-Currently sets to 256
Block device 253: 0
[Root @ centos6 ~] # Df-h/mnt/lvm/
Filesystem Size Used Avail Use % Mounted on
/Dev/mapper/vg_1-lv_1 15G 166 M 14G 2%/mnt/lvm # View/mnt/lvm directory capacity is still 15G, no change
[Root @ centos6 ~] # Dumpe2fs/dev/vg_1/lv_1

(5) Use the resize2fs command to expand the LV capacity to the entire file system;

[Root @ centos6 ~] # Resize2fs/dev/vg_1/lv_1
Resize2fs 1.41.12 (17-May-2010)
Filesystem at/dev/vg_1/lv_1 is mounted on/mnt/lvm; on-line resizing required
Old desc_blocks = 1, new_desc_blocks = 2
Ming an on-line resize of/dev/vg_1/lv_1 to 5242880 (4 k) blocks.
The filesystem on/dev/vg_1/lv_1 is now 5242880 blocks long.
[Root @ centos6 ~] # Df-h/mnt/lvm/
Filesystem Size Used Avail Use % Mounted on
/Dev/mapper/vg_1-lv_1 20G 170 M 19G 1%/mnt/lvm #/mnt/lvm directory capacity has changed to 20G