获取磁盘信息License: Attribution-NonCommercial-ShareAlike 4.0 International
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# qemu-img info /opt/data/kvm/images/hello_kvm.img
image: /opt/data/kvm/images/hello_kvm.img
file format: qcow2
virtual size: 10G (10737418240 bytes)
disk size: 1.1G
cluster_size: 65536
Format specific information:
compat: 1.1
lazy refcounts: true
创建磁盘镜像文件
# qemu-img create -f qcow2 ubuntu.img 20G磁盘扩容
# qemu-img resize /opt/data/kvm/images/hello_kvm.img +5G
Image resized.
# qemu-img info /opt/data/kvm/images/hello_kvm.img
image: /opt/data/kvm/images/hello_kvm.img
file format: qcow2
virtual size: 15G (16106127360 bytes)
disk size: 1.1G
cluster_size: 65536
Format specific information:
compat: 1.1
lazy refcounts: true
# virsh destroy hello_kvm
# virsh start hello_kvm
# virsh console hello_kvm
# fdisk /dev/vda
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.
Command (m for help): p
Disk /dev/vda: 16.1 GB, 16106127360 bytes, 31457280 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000dd1eb
Device Boot Start End Blocks Id System
/dev/vda1 * 2048 1026047 512000 83 Linux
/dev/vda2 1026048 20971519 9972736 8e Linux LVM
Command (m for help): n
Partition type:
p primary (2 primary, 0 extended, 2 free)
e extended
Select (default p): p
Partition number (3,4, default 3):
First sector (20971520-31457279, default 20971520):
Using default value 20971520
Last sector, +sectors or +size{K,M,G} (20971520-31457279, default 31457279):
Using default value 31457279
Partition 3 of type Linux and of size 5 GiB is set
Command (m for help): p
Disk /dev/vda: 16.1 GB, 16106127360 bytes, 31457280 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000dd1eb
Device Boot Start End Blocks Id System
/dev/vda1 * 2048 1026047 512000 83 Linux
/dev/vda2 1026048 20971519 9972736 8e Linux LVM
/dev/vda3 20971520 31457279 5242880 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
# 分区生效
partprobe# 查看分区
# df -Th --total Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 8.5G 788M 7.7G 10% / devtmpfs devtmpfs 236M 0 236M 0% /dev tmpfs tmpfs 245M 0 245M 0% /dev/shm tmpfs tmpfs 245M 4.4M 241M 2% /run tmpfs tmpfs 245M 0 245M 0% /sys/fs/cgroup /dev/vda1 xfs 497M 120M 378M 25% /boot total - 9.9G 912M 9.1G 9% -# 创建物理卷
# pvcreate /dev/vda3 Physical volume "/dev/vda3" successfully created # vgs VG #PV #LV #SN Attr VSize VFree centos 1 2 0 wz--n- 9.51g 40.00m把物理卷分区加进卷组
# vgextend centos /dev/vda3
Volume group "centos" successfully extended
# vgs
VG #PV #LV #SN Attr VSize VFree
centos 2 2 0 wz--n- 14.50g 5.04g
# lvextend -L +2G /dev/mapper/centos-root
Size of logical volume centos/root changed from 8.47 GiB (2168 extents) to 10.47 GiB (2680 extents).
Logical volume root successfully resized
XFS
# xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=256 agcount=4, agsize=555008 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=2220032, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 2220032 to 2744320
EXT
resize2fs /dev/mapper/centos-root
添加虚拟磁盘
# mkdir /opt/data/kvm/disk # qemu-img create -f qcow2 /opt/data/kvm/disk/hello_kvm.qcow2 5G # virsh destroy hello_kvm # virsh edit hello_kvm添加新的磁盘
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/opt/data/kvm/disk/hello_kvm.qcow2'/>
<target dev='vdb' bus='virtio'/>
</disk>
# virsh start hello_kvm
[root@hello-kvm ~]# fdisk -l /dev/vdb
Disk /dev/vdb: 5368 MB, 5368709120 bytes, 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
# mkfs [-t <type>] /dev/vdb
# vim /etc/fstab
# mount -a
