常用的虚拟机管理命令
列出所有的虚拟机 virsh list --all 显示虚拟机信息 virsh dominfo kvm-1 显示虚拟机内存和cpu的使用情况 yum install virt-top -y virt-top 显示虚拟机分区信息 virt-df kvm-1 关闭虚拟机（shutodwn） virsh shutdown kvm-1 启动虚拟机 virsh start kvm-1 设置虚拟机（kvm-1）跟随系统自启 virsh autostart kvm-1 关闭虚拟及自启 virsh autostart --disable kvm-1 删除虚拟机 virsh undefine kvm-1 通过控制窗口登录虚拟机 virsh console kvm-1添加硬盘（lvm卷）或者USB到虚拟机上
virsh attach-disk kvm-1 /dev/sdb vbd --driver qemu --mode shareable 使用完成之后可以卸载usb virsh detach-disk kvm vdb添加lvm卷，并挂载
[root@sh-kvm-1 ~]# lvcreate -n kvm-1-data -L 50G vg_shkvm1 [root@sh-kvm-1 ~]# virsh attach-disk kvm-1 /dev/vg_shkvm1/kvm-1-data vdb --driver qemu --mode shareable Disk attached successfully # 登录到kvm-1上查看lvm是否已经被挂载 [root@sh-kvm-1 ~]# virsh console kvm-1 # 输入kvm-1的用户和密码 [root@sh-kvm-1-1 ~]# fdisk -l # 查看硬盘挂载情况 Disk /dev/vda: 21.5 GB, 21474836480 bytes 16 heads, 63 sectors/track, 41610 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: 0x00058197 Device Boot Start End Blocks Id System /dev/vda1 * 3 1018 512000 83 Linux Partition 1 does not end on cylinder boundary. /dev/vda2 1018 41611 20458496 8e Linux LVM Partition 2 does not end on cylinder boundary. Disk /dev/mapper/VolGroup-lv_root: 18.8 GB, 18798870528 bytes 255 heads, 63 sectors/track, 2285 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: 2147 MB, 2147483648 bytes 255 heads, 63 sectors/track, 261 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/vdb: 53.7 GB, 53687091200 bytes # 新添加的硬盘 16 heads, 63 sectors/track, 104025 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 格式化新添加的vdb，并添加到lvm组中 # 对新添加的硬盘分区 [root@sh-kvm-1-1 ~]# fdisk /dev/vdb Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel Building a new DOS disklabel with disk identifier 0xf04b6807. Changes will remain in memory only, until you decide to write them. After that, of course, the previous content won't be recoverable. Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite) WARNING: DOS-compatible mode is deprecated. It's strongly recommended to switch off the mode (command 'c') and change display units to sectors (command 'u'). Command (m for help): m # 查看帮助 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 partition table 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 (experts only) Command (m for help): n #添加一个分区 Command action e extended p primary partition (1-4) p #选择添加一个扩展分区 Partition number (1-4): Value out of range. Partition number (1-4): 1 First cylinder (1-104025, default 1): Using default value 1 Last cylinder, +cylinders or +size{K,M,G} (1-104025, default 104025): Using default value 104025 Command (m for help): t #改变分区的格式 Selected partition 1 Hex code (type L to list codes): 8e #改成lvm Changed system type of partition 1 to 8e (Linux LVM) Command (m for help): w # 保存更改 root@sh-kvm-1-1 ~]# mkfs.ext4 /dev/vdb1 # 格式化分区 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 3276800 inodes, 13107142 blocks 655357 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=4294967296 400 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 4096000, 7962624, 11239424 Writing inode tables: done Creating journal (32768 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 28 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@sh-kvm-1-1 ~]# pvc reate /dev/vdb1 # 创建pv vdb vdb1 [root@sh-kvm-1-1 ~]# vgextend VolGroup /dev/vdb # 扩展lvm vg vdb vdb1 [root@sh-kvm-1-1 ~]# vgs VG #PV #LV #SN Attr VSize VFree VolGroup 2 2 0 wz--n- 69.50g 50.00g # 从上面能看出，新添加的 已经加到lvm组中通过命令行更改创建之后虚拟机的内存，cpu等信息
更改内存 # 1. 查看虚拟机当前内存 [root@sh-kvm-1 ~]# virsh dominfo kvm-1 | grep memory Max memory: 4194304 KiB Used memory: 4194304 KiB # 2、动态设置内存为512MB，内存减少 virsh setmem kvm-1 524288 # 注意单位必须是KB # 3、查看内存变化 # virsh dominfo kvm-1 | grep memory Max memory: 14194304 KiB Used memory: 524288 kiB # 4、内存增加 virsh shutdown kvm-1 virsh edit kvm-1 # 直接更改memory virsh create /etc/libvirt/demu/kvm-1/xml # 之后操作1,2,3步骤增加内存 更改CPU需要修改配置文件，因此需要停止虚拟机
virsh shutdown kvm-1 virsh edit kvm-1 # <vcpu>2</vcpu> # 4 > 2 virsh create /etc/libvirt/demu/kvm-1/xml 硬盘扩容 1. Create a 10-GB non-sparse file: # dd if=/dev/zero of=/vm-images/vm1-add.img bs=1M count=10240 2. Shutdown the VM: # virsh shutdown vm1 3. Add an extra entry for ‘disk’ in the VM's XML file in /etc/libvirt/qemu. You can look copy & paste the entry for your mail storage device and just change the target and address tags. For example: # virsh edit vm1 <disk type='file' device='disk'> <driver name='qemu' type='raw' cache='none' io='threads'/> <source file='/vm-images/vm1.img'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </disk> Add: <disk type='file' device='disk'> <driver name='qemu' type='raw' cache='none' io='threads'/> <source file='/vm-images/vm1-add.img'/> <target dev='vdb' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </disk> # 这里建议使用上面的添加硬盘的方式添加