一 KVM对用户提供的命令主要在/usr/bin/目录下
[root@centoskvm ~]# ls /usr/bin/vir*
/usr/bin/virsh /usr/bin/virt-manager
/usr/bin/virt-clone /usr/bin/virt-pki-validate
/usr/bin/virt-convert /usr/bin/virt-top
/usr/bin/virt-host-validate /usr/bin/virt-viewer
/usr/bin/virt-image /usr/bin/virt-who
/usr/bin/virt-install /usr/bin/virt-xml-validate
[root@centoskvm ~]# ls /usr/bin/qe*
/usr/bin/qemu-img /usr/bin/qemu-io /usr/bin/qemu-kvm
常用的命令有:virsh,virsh-install,virsh-clone,virsh-convert,virsh-image,qemu-img和qemu-kvm
二 virsh常用的管理命令
使用xml配置文件开启虚拟机
[root@centoskvm kvm]# virsh create 1003vm.xml
Domain 1003vm created from 1003vm.xml
列出虚拟机：
[root@centoskvm kvm]# virsh list
Id Name State
----------------------------------------------------
13 1003vm running
Id和Name可以作为控制虚拟机的主键
列出域中全部的虚拟机：
[root@centoskvm kvm]# virsh list --all
Id Name State
----------------------------------------------------
13 1003vm running
- 1001vm shut off
关闭虚拟机：
[root@centoskvm kvm]# virsh shutdown 13
或者
[root@centoskvm kvm]# virsh shutdown 1003vm
重启虚拟机：
[root@centoskvm kvm]#virsh reboot 13
或者
[root@centoskvm kvm]# virsh reboot 1003vm
强制关闭虚拟机：（不建议使用，这样容易破坏虚拟机的文件系统）
[root@centoskvm kvm]#virsh destroy 13
或者
[root@centoskvm kvm]# virsh destroy 1003vm
添加虚拟机：
[root@centoskvm kvm]#virsh define /home/kvm/1002vm.xml #根据主机配置文档添加虚拟机
Domain 1002vm defined from /home/kvm/1002vm.xml
[root@centoskvm kvm]# virsh list --all
Id Name State
----------------------------------------------------
13 1003vm running
- 1001vm shut off
- 1002vm shut off #1002vm已被添加到域中
移除虚拟机：
[root@centoskvm kvm]#virsh undefine 1002vm
Domain 1002vm has been undefined
[root@centoskvm kvm]# virsh list --all
Id Name State
----------------------------------------------------
13 1003vm running
- 1001vm shut off
#1002vm已被从域中移除
导出虚拟机的配置信息xml文件
[root@centoskvm kvm]# virsh dumpxml 1003vm > ~/1003vm.xml
[root@centoskvm kvm]# cat ~/1003vm.xml
<domaintype='kvm' id='13'>
<name>1003vm</name>
<uuid>323286df-2fa9-9864-4754-b51df76bd336</uuid>
<memory unit='KiB'>2097152</memory>
<currentMemory unit='KiB'>2097152</currentMemory>
<vcpu placement='static'>2</vcpu>
<os>
<type arch='x86_64' machine='rhel6.2.0'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
<pae/>
</features>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='raw' cache='none'/>
<source file='/home/kvm/1003vm.img'/>
<target dev='vda' bus='virtio'/>
<shareable/>
<alias name='virtio-disk0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
</disk>
<controller type='usb' index='0'>
<alias name='usb0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
</controller>
<interface type='bridge'>
<mac address='52:54:00:88:f8:03'/>
<source bridge='br0'/>
<target dev='vnet0'/>
<model type='virtio'/>
<alias name='net0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
<serial type='pty'>
<source path='/dev/pts/1'/>
<target port='0'/>
<alias name='serial0'/>
</serial>
<console type='pty' tty='/dev/pts/1'>
<source path='/dev/pts/1'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<input type='tablet' bus='usb'>
<alias name='input0'/>
</input>
<input type='mouse' bus='ps2'/>
<graphics type='vnc' port='5900' listen='127.0.0.1'>
<listen type='address' address='127.0.0.1'/>
</graphics>
<video>
<model type='cirrus' vram='9216' heads='1'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
</video>
<memballoon model='virtio'>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
</memballoon>
</devices>
<seclabel type='dynamic' model='selinux' relabel='yes'>
<label>system_u:system_r:svirt_t:s0:c97,c672</label>
<imagelabel>system_u:object_r:svirt_image_t:s0:c97,c672</imagelabel>
</seclabel>
</domain>
也可以使用xml配置来启动虚拟机：
[root@centoskvm kvm]# virsh shutdown 1003vm
[root@centoskvm kvm]# virsh list --all
Id Name State
----------------------------------------------------
- 1003vm shut off
- 1001vm shut off
[root@centoskvm kvm]# virsh create ~/1003vm.xml
[root@centoskvm kvm]# virsh list --all
Id Name State
----------------------------------------------------
14 1003vm running
- 1001vm shut off
三 使用命令接口创建虚拟机
创建镜像文件：
[root@centoskvm kvm]# qemu-img create -f qcow2 /home/kvm/1001vm.img 16G
查看img文件信息：
[root@centoskvm img]# qemu-img info 1001vm.img
image: 1001vm.img
file format: qcow2
virtual size: 16G (17179869184 bytes)
disk size: 5.9G
cluster_size: 65536
其中参数 -f 表示镜像文件的格式[qcow2]，具体介绍如下：
[root@centoskvm img]# qemu-img create --help
create: invalid option -- '-'
qemu-img version 0.12.1, Copyright (c) 2004-2008 Fabrice Bellard
usage: qemu-img command [command options]
QEMU disk image utility
Command syntax:
check [-f fmt] filename
create [-f fmt] [-o options] filename [size]
commit [-f fmt] [-t cache] filename
convert [-c] [-p] [-f fmt] [-t cache] [-O output_fmt] [-o options] [-S sparse_size] filename [filename2 [...]] output_filename
info [-f fmt] filename
snapshot [-l | -a snapshot | -c snapshot | -d snapshot] filename
rebase [-f fmt] [-t cache] [-p] [-u] -b backing_file [-F backing_fmt] filename
resize filename [+ | -]size
Command parameters:
'filename' is a disk image filename
'fmt' is the disk image format. It is guessed automatically in most cases
'cache' is the cache mode used to write the output disk image, the valid
options are: 'none', 'writeback' (default), 'writethrough' and 'unsafe'
'size' is the disk image size in bytes. Optional suffixes
'k' or 'K' (kilobyte, 1024), 'M' (megabyte, 1024k), 'G' (gigabyte, 1024M)
and T (terabyte, 1024G) are supported. 'b' is ignored.
'output_filename' is the destination disk image filename
'output_fmt' is the destination format
'options' is a comma separated list of format specific options in a
name=value format. Use -o ? for an overview of the options supported by the
used format
'-c' indicates that target image must be compressed (qcow format only)
'-u' enables unsafe rebasing. It is assumed that old and new backing file
match exactly. The image doesn't need a working backing file before
rebasing in this case (useful for renaming the backing file)
'-h' with or without a command shows this help and lists the supported formats
'-p' show progress of command (only certain commands)
'-S' indicates the consecutive number of bytes that must contain only zeros
for qemu-img to create a sparse image during conversion
Parameters to snapshot subcommand:
'snapshot' is the name of the snapshot to create, apply or delete
'-a' applies a snapshot (revert disk to saved state)
'-c' creates a snapshot
'-d' deletes a snapshot
'-l' lists all snapshots in the given image
Supported formats: raw cow qcow vdi vmdk cloop dmg bochs vpc vvfat qcow2 qed parallels nbd blkdebug host_cdrom host_floppy host_device file
常用的格式为raw和qcow2，推荐使用qcow2格式。
raw格式：可以简单、容易地导出到其它模拟器中，但是立即分配占用空间大。
qcow2格式：是qcow格式的升级版本，是目前最万能的格式。使用它可获得较小映像，也是虚拟池一直在使用的镜像格式，支持镜像快照，方便的恢复管理。
安装虚拟机客户操作系统：
[root@centoskvm img]#virt-install --name 1001vm --ram=1024 --arch=x86_64 --vcpus=2 --check-cpu --os-type=linux --os-variant='rhel6' -c /home/mysoft/os/CentOS-6.2-x86_64-bin-DVD1.iso --disk path=/home/img/1001vm.img,device=disk,bus=virtio,format=qcow2 --bridge=br0 --noautoconsole --vnc --vncport=5902 --vnclisten=0.0.0.0
[root@centoskvm img]# virt-install --help
Usage: virt-install --name NAME --ram RAM STORAGE INSTALL [options]
Options:
--version show program's version number and exit
-h, --help show this help message and exit
--connect=URI Connect to hypervisor with libvirt URI
General Options:
-n NAME, --name=NAME
Name of the guest instance
-r MEMORY, --ram=MEMORY
Memory to allocate for guest instance in megabytes
--vcpus=VCPUS Number of vcpus to configure for your guest. Ex:
--vcpus 5
--vcpus 5,maxcpus=10
--vcpus sockets=2,cores=4,threads=2
--cpuset=CPUSET Set which physical CPUs domain can use.
--cpu=CPU CPU model and features. Ex: --cpu coreduo,+x2apic
--description=DESCRIPTION
Human readable description of the VM to store in the
generated XML.
--security=SECURITY
Set domain security driver configuration.
--numatune=NUMATUNE
Tune NUMA policy for the domain process.
Installation Method Options:
-c CDROM, --cdrom=CDROM
CD-ROM installation media
-l LOCATION, --location=LOCATION
Installation source (eg, nfs:host:/path,
http://host/path, ftp://host/path)
--pxe Boot from the network using the PXE protocol
--import Build guest around an existing disk image
--init=INIT Path to init binary for container guest. Ex:
--init /path/to/app (to contain an application)
--init /sbin/init (for a full OS container)
--livecd Treat the CD-ROM media as a Live CD
-x EXTRA, --extra-args=EXTRA
Additional arguments to pass to the install kernel
booted from --location
--initrd-inject=INITRD_INJECTIONS
Add given file to root of initrd from --location
--os-type=DISTRO_TYPE
The OS type being installed, e.g. 'linux', 'unix',
'windows'
--os-variant=DISTRO_VARIANT
The OS variant being installed guests, e.g. 'fedora6',
'rhel5', 'solaris10', 'win2k'
--boot=BOOTOPTS Optionally configure post-install boot order, menu,
permanent kernel boot, etc.
Storage Configuration:
--disk=DISKOPTS Specify storage with various options. Ex.
--disk path=/my/existing/disk
--disk path=/my/new/disk,size=5 (in gigabytes)
--disk vol=poolname:volname,device=cdrom,bus=scsi,...
--nodisks Don't set up any disks for the guest.
--filesystem=FILESYSTEMS
Pass host directory to the guest. Ex:
--filesystem /my/source/dir,/dir/in/guest
--filesystem template_name,/,type=template
Networking Configuration:
-w NETWORK, --network=NETWORK
Configure a guest network interface. Ex:
--network bridge=mybr0
--network network=my_libvirt_virtual_net
--network network=mynet,model=virtio,mac=00:11...
--nonetworks Don't create network interfaces for the guest.
Graphics Configuration:
--graphics=GRAPHICS
Configure guest display settings. Ex:
--graphics vnc
--graphics spice,port=5901,tlsport=5902
--graphics none
--graphics vnc,password=foobar,port=5910,keymap=ja
--noautoconsole Don't automatically try to connect to the guest
console
Device Options:
--serial=SERIALS Configure a guest serial device
--parallel=PARALLELS
Configure a guest parallel device
--channel=CHANNELS Configure a guest communication channel
--console=CONSOLES Configure a text console connection between the guest
and host
--host-device=HOSTDEVS
Configure physical host devices attached to the guest
--soundhw=SOUNDHW Configure guest sound device emulation
--watchdog=WATCHDOG
Configure a guest watchdog device
--video=VIDEO Configure guest video hardware.
--smartcard=SMARTCARD
Configure a guest smartcard device. Ex:
--smartcard mode=passthrough
Virtualization Platform Options:
-v, --hvm This guest should be a fully virtualized guest
-p, --paravirt This guest should be a paravirtualized guest
--container This guest should be a container guest
--virt-type=HV_TYPE
Hypervisor name to use (kvm, qemu, xen, ...)
--arch=ARCH The CPU architecture to simulate
--machine=MACHINE The machine type to emulate
--noapic Disables APIC for fully virtualized guest (overrides
value in os-type/os-variant db)
--noacpi Disables ACPI for fully virtualized guest (overrides
value in os-type/os-variant db)
-u UUID, --uuid=UUID
UUID for the guest.
Miscellaneous Options:
--autostart Have domain autostart on host boot up.
--print-xml Print the generated domain XML rather than define the
guest.
--print-step=XMLSTEP
Print XML of a specific install step (1, 2, 3, all)
rather than define the guest.
--noreboot Don't boot guest after completing install.
--wait=WAIT Time to wait (in minutes)
--dry-run Run through install process, but do not create devices
or define the guest.
--force Forces 'yes' for any applicable prompts, terminates
for all others
-q, --quiet Suppress non-error output
--prompt Request user input for ambiguous situations or
required options.
-d, --debug Print debugging information
四 使用console登录虚拟机
[root@centoskvm img]#virsh list
Id Name State
----------------------------------------------------
13 1003vm running
[root@centoskvm img]# virshconsole 13
若出现无法从console登录的情况，会卡在“
Escape character is ^]”处无法继续。请从桌面以root登录做如下操作：
1、添加ttyS0的安全许可，允许root登录:
[root@1001vm img]# echo "ttyS0" >> /etc/securetty
[root@1001vm ~]# cat /etc/securetty
console
vc/1
vc/2
。。。。。。
vc/10
vc/11
tty1
tty2
。。。。。。
tty11
ttyS0
2、在/etc/grub.conf文件中为内核添加参数:console=ttyS0
[root@1001vm ~]# cat /etc/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_1001vm-lv_root
# initrd /initrd-[generic-]version.img
#boot=/dev/vda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (2.6.32-220.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-220.el6.x86_64 ro root=/dev/mapper/vg_1001vm-lv_root rd_NO_LUKS rd_LVM_LV=vg_1001vm/lv_root LANG=en_US.UTF-8 rd_NO_MD quiet SYSFONT=latarcyrheb-sun16 rhgb crashkernel=auto rd_LVM_LV=vg_1001vm/lv_swap KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM console=ttyS0
initrd /initramfs-2.6.32-220.el6.x86_64.img
3、在/etc/inittab中添加agetty:
S0:12345:respawn:/sbin/agetty ttyS0 115200
[root@1001vm ~]# cat /etc/inittab
# inittab is only used by upstart for the default runlevel.
#。。。。。。。。。。。。。
#。。。。。。。。。。。。。
id:5:initdefault:
S0:12345:respawn:/sbin/agetty ttyS0 115200
4、重启客户虚拟机:
[root@1001vm img]# reboot
此时，再次尝试console命令可以正常使用:
[root@centoskvm img]# virsh console 1001vm
Connected to domain 1001vm
Escape character is ^]
[ OK ]
Setting hostname 1001vm: [ OK ]
Setting up Logical Volume Management: 2 logical volume(s) in volume group "vg_1001vm" now active
[ OK ]
。。。。。。。。。。。。。。。。。。。。。。。。。。。。
。。。。。。。。。。。。。。。。。。。。。。。。。。。。
Starting atd: [ OK ]
Starting up CIM server: [ OK ]
CentOS release 6.2 (Final)
Kernel 2.6.32-220.el6.x86_64 on an x86_64
1001vm login: root
Password:
[root@1001vm ~]#
