Enlarge RootFS In CentOS7
Aug 6, 2015
Technology
Disk Preparation
Create a new disk via following command in host machine:
# qemu-img create -f qcow2 Added.qcow2 200G
Boot the machine and you will have the newly added disk as /dev/vdb, format it via
fdisk.
[root@spacewalker ~]# fdisk /dev/vdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0x694e59ec.
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1):
First sector (2048-419430399, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-419430399, default 419430399):
Using default value 419430399
Partition 1 of type Linux and of size 200 GiB is set
Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
You can use partprobe /dev/sda for probing the partitions.
Physical Volume
Create a physical volume and display the pv:
[root@spacewalker ~]# pvcreate /dev/vdb1
Physical volume "/dev/vdb1" successfully created
[root@spacewalker ~]# pvdisplay
--- Physical volume ---
PV Name /dev/vda3
VG Name rootvg01
PV Size 96.46 GiB / not usable 23.00 MiB
Allocatable yes (but full)
PE Size 32.00 MiB
Total PE 3086
Free PE 0
Allocated PE 3086
PV UUID rq51pP-o3Pw-8mMs-kBiN-wLva-nfLf-Svd9uk
"/dev/vdb1" is a new physical volume of "200.00 GiB"
--- NEW Physical volume ---
PV Name /dev/vdb1
VG Name
PV Size 200.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID cPijvf-qPYT-w4yi-MsFo-yEHs-O9t8-6FmXUU
Add pv into VG(Volume group)
First vgdisplay for get the VG name, then added it into vg, check the free pe, now its 200 GiB available.
[root@spacewalker ~]# vgdisplay
--- Volume group ---
VG Name rootvg01
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 2
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 1
Act PV 1
VG Size 96.44 GiB
PE Size 32.00 MiB
Total PE 3086
Alloc PE / Size 3086 / 96.44 GiB
Free PE / Size 0 / 0
VG UUID U98QSe-V6Kv-aYSf-cSsp-ln0H-IhuS-1oNsgV
[root@spacewalker ~]# vgextend rootvg01 /dev/vdb1
Volume group "rootvg01" successfully extended
[root@spacewalker ~]# vgdisplay
--- Volume group ---
VG Name rootvg01
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 3
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 2
Act PV 2
VG Size 296.41 GiB
PE Size 32.00 MiB
Total PE 9485
Alloc PE / Size 3086 / 96.44 GiB
Free PE / Size 6399 / 199.97 GiB
VG UUID U98QSe-V6Kv-aYSf-cSsp-ln0H-IhuS-1oNsgV
Enlarge the lv
Use following command for first get the lv name, then lvextend to the most available space of the volume group.
[root@spacewalker ~]# lvdisplay
--- Logical volume ---
LV Path /dev/rootvg01/lv01
LV Name lv01
VG Name rootvg01
LV UUID 5U4JM5-nG7G-TdPd-6zZ0-fE05-oysa-jEJHQu
LV Write Access read/write
LV Creation host, time localhost, 2015-07-29 18:11:18 +0800
LV Status available
# open 1
LV Size 96.44 GiB
Current LE 3086
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
[root@spacewalker ~]# lvextend -l +100%FREE /dev/rootvg01/lv01
Size of logical volume rootvg01/lv01 changed from 96.44 GiB (3086 extents) to 296.41 GiB (9485 extents).
Logical volume lv01 successfully resized
[root@spacewalker ~]# lvdisplay
--- Logical volume ---
LV Path /dev/rootvg01/lv01
LV Name lv01
VG Name rootvg01
LV UUID 5U4JM5-nG7G-TdPd-6zZ0-fE05-oysa-jEJHQu
LV Write Access read/write
LV Creation host, time localhost, 2015-07-29 18:11:18 +0800
LV Status available
# open 1
LV Size 296.41 GiB
Current LE 9485
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
Enlarge in the system level:
[root@spacewalker ~]# df -HT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/rootvg01-lv01 xfs 104G 19G 85G 19% /
devtmpfs devtmpfs 1.1G 0 1.1G 0% /dev
tmpfs tmpfs 1.1G 0 1.1G 0% /dev/shm
tmpfs tmpfs 1.1G 8.7M 1.1G 1% /run
tmpfs tmpfs 1.1G 0 1.1G 0% /sys/fs/cgroup
/dev/vda1 xfs 207M 111M 96M 54% /boot
[root@spacewalker ~]# xfs_growfs /dev/rootvg01/lv01
meta-data=/dev/mapper/rootvg01-lv01 isize=256 agcount=4, agsize=6320128 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=25280512, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal bsize=4096 blocks=12344, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 25280512 to 77701120
[root@spacewalker ~]# df -HT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/rootvg01-lv01 xfs 319G 19G 300G 6% /
devtmpfs devtmpfs 1.1G 0 1.1G 0% /dev
tmpfs tmpfs 1.1G 0 1.1G 0% /dev/shm
tmpfs tmpfs 1.1G 8.7M 1.1G 1% /run
tmpfs tmpfs 1.1G 0 1.1G 0% /sys/fs/cgroup
/dev/vda1 xfs 207M 111M 96M 54% /boot
Now you could enjoy the 300G size diskspace.
Tips on ext4
The Steps are quite the same, but resize via following command:
# qemu-img resize xxx.qcow2 +300G
# lvextend -l +100%FREE /dev/vg_centos/lv_root
# resize2fs /dev/vg_centos/lv_root
Or you extend to specified disk size:
[root@csmgmt home]# lvextend -L +500G /dev/vg_centos/lv_root
Size of logical volume vg_centos/lv_root changed from 50.00 GiB (12800
extents) to 550.00 GiB (140800 extents).
Logical volume lv_root successfully resized
[root@csmgmt home]# resize2fs /dev/vg_centos/lv_root