KVM如何在线添加新硬盘：
1）新建一个qcow2格式的大小为5G，磁盘名称为centos67_add.qcow2的磁盘
[root@kvm-server01 ~]# cd /kvmdata/ [root@kvm-server01 kvmdata]# ls centos67.qcow2 win2003.qcow2 [root@kvm-server01 kvmdata]# qemu-img create -f qcow2 centos67_add.qcow2 5G Formatting 'centos67_add.qcow2', fmt=qcow2 size=5368709120 encryption=off cluster_size=65536
2）查看磁盘的详细信息
[root@kvm-server01 kvmdata]# qemu-img info centos67_add.qcow2 p_w_picpath: centos67_add.qcow2 file format: qcow2 virtual size: 5.0G (5368709120 bytes) disk size: 136K cluster_size: 65536
3）将磁盘附加到虚拟机centos67中
[root@kvm-server01 kvmdata]# virsh attach-disk centos67 /kvmdata/centos67_add.qcow2 vda --cache=none --subdriver=qcow2 Disk attached successfully
4）在虚拟机中进行验证
[root@centos67-mini ~]# fdisk -l Disk /dev/sda: 10.7 GB, 10737418240 bytes 255 heads, 63 sectors/track, 1305 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: 0x0007bea2 Device Boot Start End Blocks Id System /dev/sda1 * 1 64 512000 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 64 1306 9972736 8e Linux LVM Disk /dev/mapper/VolGroup-lv_root: 9168 MB, 9168748544 bytes 255 heads, 63 sectors/track, 1114 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/VolGroup-lv_swap: 1040 MB, 1040187392 bytes 255 heads, 63 sectors/track, 126 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/vda: 5368 MB, 5368709120 bytes 16 heads, 63 sectors/track, 10402 cylinders Units = cylinders of 1008 * 512 = 516096 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000
注：再次说明只有RHEL/CentOS/OEL6.x及高版本的在线添加磁盘，虚拟机直接可以在线识别。
