《KVM实战：原理、进阶与性能调优》
目录
1. libvirt
1.1 libvirt 简介
什么是 libvirt
libvirt 是目前使用最为广泛的对 KVM 虚拟机进行管理的工具和 API，主要作为连接底层 Hypervisor 和上层应用程序的一个中间适配层。
libvirt 支持多种 Hypervisor
主要模块
libvirt 主要包含三个模块：
- 守护进程
libvirtd：接收并处理 API 请求 - API 库：可基于此 API 开发管理工具，例如
virt-manager virsh是经常会使用到的 KVM 命令行管理工具
层次结构
libvirt 的层次结构
libvirt 总体上可分为三个层次：
- 公共接口层（Public API Layer）
- 驱动接口层（Driver API Layer）
- 驱动实现层（Driver Implementation Layer）
重要概念
另外，在libvirt 中涉及到以下几个重要概念：
- 节点
Node：是一个物理机器，上面可能运行着多个虚拟客户机。Hypervisor和Domain都运行在节点上 Hypervisor：也称虚拟机监控器（VMM），如 KVM、Xen、VMWare、Hyper-V 等，是虚拟化中的一个底层软件层，它可以虚拟化一个节点使其运行多个虚拟客户机- 域
Domain：是在Hypervisor上运行的一个客户机操作系统实例。域也被称为实例（instance）、客户机操作系统（Guest OS）或虚拟机（VM），它们都是同一个概念
管理功能
libvirt 的管理功能主要包含以下五个部分：
- 域的管理：包括对节点上的域的各个生命周期的管理，如启动、停止、暂停、保存、恢复和动态迁移，以及对多种设备类型的热拔插操作
- 远程节点的管理：只要物理节点上运行了
libvirtd守护进程，远程的管理程序就可以连接到该节点进行管理操作。libvirt 支持多种网络远程传输类型，如 SSH、TCP 套接字、Unix domain socket、TLS 的加密传输等。例如，可通过virsh -c qemu+ssh://root@example.com/system连接到example.com上，从而管理其上的域 - 存储的管理：任何运行了
libvirtd守护进程的主机，都可以通过 libvirt 来管理不同类型的存储，如创建不同格式的客户机镜像、挂载 NFS、查看现有的 LVM 卷组、创建新的 LVM 卷组和逻辑卷、对磁盘设备分区、挂载 iSCSI 共享存储、使用 Ceph 系统支持的 RBD 远程存储等 - 网络的管理：列出现有的网络接口、配置网络接口、创建虚拟网络接口、桥接、VLAN 管理、NAT 网络设置、为客户机分配虚拟网络等
- 提供一个稳定、可靠、高效的 API，以便可以完成前面的四个管理功能
1.2 libvirt 的安装与配置
安装 libvirt
在CentOS 7.5中，部分 libvirt 相关的包如下所示：
> yum install libvirt
> rpm -qa | grep libvirt
libvirt-daemon-driver-network-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-mpath-4.5.0-10.el7_6.6.x86_64
libvirt-libs-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-config-network-4.5.0-10.el7_6.6.x86_64
libvirt-python-4.5.0-1.el7.x86_64
libvirt-daemon-driver-storage-rbd-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-kvm-4.5.0-10.el7_6.6.x86_64
libvirt-gconfig-1.0.0-1.el7.x86_64
libvirt-bash-completion-4.5.0-10.el7_6.6.x86_64
libvirt-glib-1.0.0-1.el7.x86_64
libvirt-daemon-driver-secret-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-lxc-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-nwfilter-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-gluster-4.5.0-10.el7_6.6.x86_64
libvirt-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-iscsi-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-interface-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-config-nwfilter-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-scsi-4.5.0-10.el7_6.6.x86_64
libvirt-devel-4.5.0-10.el7_6.6.x86_64
libvirt-client-4.5.0-10.el7_6.6.x86_64
libvirt-gobject-1.0.0-1.el7.x86_64
libvirt-daemon-driver-nodedev-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-qemu-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-disk-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-core-4.5.0-10.el7_6.6.x86_64
libvirt-daemon-driver-storage-logical-4.5.0-10.el7_6.6.x86_64
libvirt 的配置文件
首先查看libvirtd的使用说明：
> libvirtd --help
Usage:
libvirtd [options]
Options:
-h | --help Display program help:
-v | --verbose Verbose messages.
-d | --daemon Run as a daemon & write PID file.
-l | --listen Listen for TCP/IP connections.
-t | --timeout <secs> Exit after timeout period.
-f | --config <file> Configuration file.
-V | --version Display version information.
-p | --pid-file <file> Change name of PID file.
libvirt management daemon:
Default paths:
Configuration file (unless overridden by -f):
/etc/libvirt/libvirtd.conf
Sockets:
/var/run/libvirt/libvirt-sock
/var/run/libvirt/libvirt-sock-ro
TLS:
CA certificate: /etc/pki/CA/cacert.pem
Server certificate: /etc/pki/libvirt/servercert.pem
Server private key: /etc/pki/libvirt/private/serverkey.pem
PID file (unless overridden by -p):
/var/run/libvirtd.pid
以CentOS 7.5为例，libvirt 的相关配置文件都在/etc/libvirt/目录中：
/etc/libvirt > ls -hl
total 80K
-rw-r--r-- 1 root root 450 Mar 14 18:25 libvirt-admin.conf
-rw-r--r-- 1 root root 547 Mar 14 18:25 libvirt.conf
-rw-r--r-- 1 root root 17K Mar 14 18:25 libvirtd.conf
-rw-r--r-- 1 root root 1.2K Mar 14 18:25 lxc.conf
drwx------. 2 root root 4.0K Apr 24 16:29 nwfilter
drwx------. 3 root root 55 May 30 11:18 qemu
-rw-r--r-- 1 root root 30K Mar 14 18:25 qemu.conf
-rw-r--r-- 1 root root 2.2K Mar 14 18:25 qemu-lockd.conf
drwx------. 2 root root 6 Nov 13 2018 secrets
drwxr-xr-x 3 root root 116 Apr 25 09:22 storage
-rw-r--r-- 1 root root 3.2K Mar 14 18:25 virtlockd.conf
-rw-r--r-- 1 root root 3.2K Mar 14 18:25 virtlogd.conf
/etc/libvirt > cd qemu
/etc/libvirt/qemu > ls -hl
total 16K
drwx------. 3 root root 42 Apr 25 10:23 networks
-rw------- 1 root root 4.1K May 30 11:18 win10.xml
-rw------- 1 root root 4.5K Apr 25 10:21 win7.xml
其中几个重要的配置文件和目录介绍如下：
(1) /etc/libvirt/libvirt.conf
libvirt.conf文件用于配置本地默认的URI连接以及一些常用libvirt远程连接的别名：
#
# This can be used to setup URI aliases for frequently
# used connection URIs. Aliases may contain only the
# characters a-Z, 0-9, _, -.
#
# Following the '=' may be any valid libvirt connection
# URI, including arbitrary parameters
#uri_aliases = [
# "hail=qemu+ssh://root@hail.cloud.example.com/system",
# "sleet=qemu+ssh://root@sleet.cloud.example.com/system",
#]
#
# These can be used in cases when no URI is supplied by the application
# (@uri_default also prevents probing of the hypervisor driver).
#
#uri_default = "qemu:///system"
uri_aliases = [
"abelsu7-ubuntu=qemu+ssh://root@abelsu7-ubuntu/system",
"centos-1=qemu+ssh://root@centos-1/system"
]
配置别名后，即可使用abelsu7-ubuntu来替代qemu+ssh://root@abelsu7-ubuntu/system远程的libvirt连接：
> systemctl reload libvirtd # 重启 libvirtd
> virsh -c abelsu7-ubuntu # 使用别名连接至远程 libvirt
Welcome to virsh, the virtualization interactive terminal.
Type: 'help' for help with commands
'quit' to quit
virsh # hostname
abelsu7-ubuntu
virsh #
当然在代码中也可以使用这个别名，例如以下 Go 代码：
package main
import (
libvirt "github.com/libvirt/libvirt-go"
)
func main() {
// conn, err := libvirt.NewConnect("qemu+ssh://root@abelsu7-ubuntu/system")
conn, err := libvirt.NewConnect("abelsu7-ubuntu")
...
...
}
(2) /etc/libvirt/libvirtd.conf
libvirtd.conf是 libvirt 的守护进程libvirtd的配置文件，被修改后需要让 libvirtd 重新加载配置文件或重启 libvirtd 才会生效。
在
libvirtd.conf中配置了libvirtd启动时的许多设置，包括是否建立 TCP、UNIX domain socket 等连接方式及其最大连接数，以及这些连接的认证机制，设置libvirtd的日志级别等
例如修改libvirtd.conf中的以下配置：
listen_tls = 0 # 关闭 TLS 安全认证的连接（默认是打开的）
listen_tcp = 1 # 打开 TCP 连接（默认是关闭的）
tcp_port = "16666" # 设置 TCP 监听的端口
unix_sock_dir = "/var/run/libvirt" # 设置 UNIX domain socket 的保存目录
auth_tcp = "none" # TCP 连接不使用认证授权方式
要让 TCP、TLS 等连接生效，需要在启动
libvirtd时加上--listen参数
修改完成后，使用systemctl命令重启libvirtd服务：
> systemctl daemon-reload
> systemctl restart libvirtd
> systemctl status libvirtd
● libvirtd.service - Virtualization daemon
Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2019-06-03 11:08:57 CST; 8s ago
Docs: man:libvirtd(8)
https://libvirt.org
Main PID: 12192 (libvirtd)
Tasks: 19 (limit: 32768)
Memory: 13.6M
CGroup: /system.slice/libvirtd.service
├─ 1827 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
├─ 1828 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
└─12192 /usr/sbin/libvirtd --listen
Jun 03 11:08:57 centos-2 systemd[1]: Starting Virtualization daemon...
Jun 03 11:08:57 centos-2 systemd[1]: Started Virtualization daemon.
Jun 03 11:08:57 centos-2 dnsmasq[1827]: read /etc/hosts - 5 addresses
Jun 03 11:08:57 centos-2 dnsmasq[1827]: read /var/lib/libvirt/dnsmasq/default.addnhosts - 0 addresses
Jun 03 11:08:57 centos-2 dnsmasq-dhcp[1827]: read /var/lib/libvirt/dnsmasq/default.hostsfile
可以看到libvirtd的启动命令已经添加了--listen参数。测试一下 TCP 连接是否可用：
> virsh -c qemu+tcp://localhost:16666/system
Welcome to virsh, the virtualization interactive terminal.
Type: 'help' for help with commands
'quit' to quit
virsh # exit
> ll /var/run/libvirt/
total 0
drwxr-xr-x 2 root root 100 Jun 3 11:08 network
srwx------ 1 root root 0 Jun 3 11:08 libvirt-admin-sock
srwxrwxrwx 1 root root 0 Jun 3 11:08 libvirt-sock
srwxrwxrwx 1 root root 0 Jun 3 11:08 libvirt-sock-ro
drwxr-xr-x 2 root root 40 May 30 11:32 qemu
srw-rw-rw- 1 root root 0 May 30 11:19 virtlogd-admin-sock
drwxr-xr-x 2 root root 40 May 29 09:47 lxc
drwxr-xr-x 2 root root 40 May 29 09:47 hostdevmgr
drwx------ 2 root root 40 May 29 09:47 nwfilter-binding
drwxr-xr-x 2 root root 40 May 29 09:47 storage
srw-rw-rw- 1 root root 0 May 29 09:47 virtlockd-sock
srw-rw-rw- 1 root root 0 May 29 09:47 virtlogd-sock
(3) /etc/libvirt/qemu.conf
qemu.conf是 libvirt 对 QEMU 的驱动配置文件，包括 VNC、SPICE 等，以及连接它们时采用的权限认证方式的配置，也包括内存大页、SELinux、Cgroups 等相关配置。
(4) /etc/libvirt/qemu 目录
在qemu目录下存放的是使用 QEMU 驱动的域的配置文件，查看qemu目录如下：
> ls -l
total 16
drwx------. 3 root root 42 Apr 25 10:23 networks
-rw------- 1 root root 4165 May 30 11:18 win10.xml
-rw------- 1 root root 4560 Apr 25 10:21 win7.xml
其中包括了两个域的 XML 配置文件（win10.xml和win7.xml），这是使用virt-manager工具创建的两个域，默认会将其保存到/etc/libvirt/qemu/目录下。
另一个networks目录则保存了创建一个域时默认使用的网络配置。
libvirtd 的使用
libvirtd是虚拟化管理系统中服务端的守护进程。要想让某个节点能够利用 libvirt 进行管理，就需要在这个节点上运行libvirtd守护进程，以便让其他上层管理工具可以连接到该节点。
在RHEL 7.3和CentOS 7.5中，libvirtd是作为一个服务配置在系统中的：
> systemctl list-unit-files | grep libvirtd
libvirtd.service enabled
> systemctl is-enabled libvirtd
enabled
> systemctl is-active libvirtd
active
> systemctl status libvirtd
● libvirtd.service - Virtualization daemon
Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2019-06-03 11:08:57 CST; 22h ago
Docs: man:libvirtd(8)
https://libvirt.org
Main PID: 12192 (libvirtd)
Tasks: 20 (limit: 32768)
Memory: 23.2M
CGroup: /system.slice/libvirtd.service
├─ 1827 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
├─ 1828 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
└─12192 /usr/sbin/libvirtd --listen
Jun 03 17:19:33 centos-2 libvirtd[12192]: 2019-06-03 09:19:33.679+0000: 12195: warning : qemuProcessVerifyHypervFeatures:3936 : host doesn't support hyper...d' feature
Jun 03 17:19:33 centos-2 libvirtd[12192]: 2019-06-03 09:19:33.679+0000: 12195: warning : qemuProcessVerifyHypervFeatures:3936 : host doesn't support hyper...c' feature
Jun 03 17:19:33 centos-2 libvirtd[12192]: 2019-06-03 09:19:33.679+0000: 12195: warning : qemuProcessVerifyHypervFeatures:3936 : host doesn't support hyper...s' feature
Jun 03 17:20:41 centos-2 dnsmasq-dhcp[1827]: DHCPDISCOVER(virbr0) 192.168.122.176 52:54:00:b1:88:3b
Jun 03 17:20:41 centos-2 dnsmasq-dhcp[1827]: DHCPOFFER(virbr0) 192.168.122.176 52:54:00:b1:88:3b
Jun 03 17:20:41 centos-2 dnsmasq-dhcp[1827]: DHCPREQUEST(virbr0) 192.168.122.176 52:54:00:b1:88:3b
Jun 03 17:20:41 centos-2 dnsmasq-dhcp[1827]: DHCPACK(virbr0) 192.168.122.176 52:54:00:b1:88:3b DESKTOP-RKPPR8A
Jun 03 17:20:46 centos-2 dnsmasq-dhcp[1827]: DHCPREQUEST(virbr0) 192.168.122.176 52:54:00:b1:88:3b
Jun 03 17:20:46 centos-2 dnsmasq-dhcp[1827]: DHCPACK(virbr0) 192.168.122.176 52:54:00:b1:88:3b DESKTOP-RKPPR8A
Jun 03 17:31:35 centos-2 libvirtd[12192]: 2019-06-03 09:31:35.081+0000: 12192: error : qemuMonitorIO:718 : internal error: End of file from qemu monitor
Hint: Some lines were ellipsized, use -l to show in full.
- 默认情况下，libvirt 监听一个本地的 Unix domain socket，而没有监听基于网络的 TCP/IP socket，需要使用
-l或者--listen的命令行参数来开启对libvirtd.conf配置文件中TCP/IP socket的监听 libvirtd守护进程的启动或停止，并不会直接影响正在运行中的客户机libvirtd在启动或重启完成时，只要客户机的 XML 配置文件是存在的，libvirtd就会自动加载这些客户机的配置，获取它们的信息- 如果客户机没有基于
libvirt格式的 XML 文件来运行（例如直接通过qemu命令行启动的客户机），libvirtd就不会自动发现它们
libvirtd 常用的命令行参数
libvirtd常用的命令行参数如下：
-d或--daemon：作为守护进程在后台运行-f或--config FILE：指定配置文件为FILE，默认为/etc/libvirt/libvirtd.conf-l或--listen：监听配置文件中的 TCP Socket-p或--pid-file FILE：将libvirtd进程的 PID 写入FILE文件中，默认为/var/run/libvirtd.pid-t或--timeout SECONDS：设置超时时间为SECONDS秒-v或--verbose：调整日志级别为Verbose-V或--version：版本号
> libvirtd --help
Usage:
libvirtd [options]
Options:
-h | --help Display program help:
-v | --verbose Verbose messages.
-d | --daemon Run as a daemon & write PID file.
-l | --listen Listen for TCP/IP connections.
-t | --timeout <secs> Exit after timeout period.
-f | --config <file> Configuration file.
-V | --version Display version information.
-p | --pid-file <file> Change name of PID file.
libvirt management daemon:
Default paths:
Configuration file (unless overridden by -f):
/etc/libvirt/libvirtd.conf
Sockets:
/var/run/libvirt/libvirt-sock
/var/run/libvirt/libvirt-sock-ro
TLS:
CA certificate: /etc/pki/CA/cacert.pem
Server certificate: /etc/pki/libvirt/servercert.pem
Server private key: /etc/pki/libvirt/private/serverkey.pem
PID file (unless overridden by -p):
/var/run/libvirtd.pid
1.3 域的 XML 配置文件
配置文件格式示例
在 libvirt 中，客户机（即域）的配置是采用 XML 格式来描述的。例如下面是我使用virt-manager创建的客户机配置文件fedora-30.xml：
<!--
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
OVERWRITTEN AND LOST. Changes to this xml configuration should be made using:
virsh edit fedora-30
or other application using the libvirt API.
-->
<domain type='kvm'>
<name>fedora-30</name>
<uuid>70b8f58a-1589-4b83-bfd1-90dfd0cc8a56</uuid>
<memory unit='KiB'>16777216</memory>
<currentMemory unit='KiB'>16777216</currentMemory>
<vcpu placement='static'>4</vcpu>
<os>
<type arch='x86_64' machine='pc-i440fx-2.11'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
<vmport state='off'/>
</features>
<cpu mode='host-model' check='partial'>
<model fallback='allow'/>
</cpu>
<clock offset='utc'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<pm>
<suspend-to-mem enabled='no'/>
<suspend-to-disk enabled='no'/>
</pm>
<devices>
<emulator>/usr/bin/kvm-spice</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/var/lib/libvirt/images/generic.qcow2'/>
<target dev='hda' bus='ide'/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<target dev='hdb' bus='ide'/>
<readonly/>
<address type='drive' controller='0' bus='0' target='0' unit='1'/>
</disk>
<controller type='usb' index='0' model='ich9-ehci1'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x7'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci1'>
<master startport='0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0' multifunction='on'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci2'>
<master startport='2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x1'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci3'>
<master startport='4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pci-root'/>
<controller type='ide' index='0'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
</controller>
<controller type='virtio-serial' index='0'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
</controller>
<interface type='network'>
<mac address='52:54:00:36:59:c3'/>
<source network='default'/>
<model type='rtl8139'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
<serial type='pty'>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
<channel type='spicevmc'>
<target type='virtio' name='com.redhat.spice.0'/>
<address type='virtio-serial' controller='0' bus='0' port='1'/>
</channel>
<input type='mouse' bus='ps2'/>
<input type='keyboard' bus='ps2'/>
<graphics type='spice' autoport='yes' listen='0.0.0.0'>
<listen type='address' address='0.0.0.0'/>
<image compression='off'/>
</graphics>
<sound model='ich6'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
</sound>
<video>
<model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
</video>
<redirdev bus='usb' type='spicevmc'>
<address type='usb' bus='0' port='1'/>
</redirdev>
<redirdev bus='usb' type='spicevmc'>
<address type='usb' bus='0' port='2'/>
</redirdev>
<memballoon model='virtio'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</memballoon>
</devices>
</domain>
如需编辑
fedora-30.xml，请使用virsh edit fedora-30命令
在该域的 XML 文件中，所有的有效配置都在<domain>和</domain>标签之间，这表明该配置文件是一个域的配置。
通过 libvirt 启动客户机，经过文件解析和命令参数的转换，最终也会调用qemu命令行工具来实际完成客户机的创建。该命令行参数非常详尽冗长，通过ps命令查询到的创建命令如下：
> ps -ef | grep qemu | grep fedora-30
libvirt+ 20817 1 0 10:23 ? 00:02:39
qemu-system-x86_64
-enable-kvm
-name guest=fedora-30,debug-threads=on
-S -object secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-35-fedora-30/master-key.aes
-machine pc-i440fx-2.11,accel=kvm,usb=off,vmport=off,dump-guest-core=off
-cpu Skylake-Client-IBRS,ss=on,vmx=on,hypervisor=on,tsc_adjust=on,clflushopt=on,ssbd=on,xsaves=on,pdpe1gb=on
-m 16384 -realtime mlock=off
-smp 4,sockets=4,cores=1,threads=1
-uuid 70b8f58a-1589-4b83-bfd1-90dfd0cc8a56
-no-user-config -nodefaults
-chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-35-fedora-30/monitor.sock,server,nowait
-mon chardev=charmonitor,id=monitor,mode=control
-rtc base=utc,driftfix=slew
-global kvm-pit.lost_tick_policy=delay
-no-hpet
-no-shutdown
-global PIIX4_PM.disable_s3=1
-global PIIX4_PM.disable_s4=1
-boot strict=on
-device ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x5.0x7
-device ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x5
-device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x5.0x1
-device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x5.0x2
-device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x6
-drive file=/var/lib/libvirt/images/generic.qcow2,format=qcow2,if=none,id=drive-ide0-0-0
-device ide-hd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=1
-drive if=none,id=drive-ide0-0-1,readonly=on
-device ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1
-netdev tap,fd=27,id=hostnet0
-device rtl8139,netdev=hostnet0,id=net0,mac=52:54:00:36:59:c3,bus=pci.0,addr=0x3
-chardev pty,id=charserial0
-device isa-serial,chardev=charserial0,id=serial0
-chardev spicevmc,id=charchannel0,name=vdagent
-device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=com.redhat.spice.0
-spice port=5900,addr=0.0.0.0,disable-ticketing,image-compression=off,seamless-migration=on
-device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pci.0,addr=0x2
-device intel-hda,id=sound0,bus=pci.0,addr=0x4
-device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0
-chardev spicevmc,id=charredir0,name=usbredir
-device usb-redir,chardev=charredir0,id=redir0,bus=usb.0,port=1
-chardev spicevmc,id=charredir1,name=usbredir
-device usb-redir,chardev=charredir1,id=redir1,bus=usb.0,port=2
-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7
-msg timestamp=on
CPU、内存、启动顺序等基本配置
关于 CPU 的配置如下：
<vcpu placement='static'>4</vcpu>
<features>
<acpi/>
<apic/>
</features>
<cpu mode='custom' match='exact'>
<model fallback='allow'>Haswell-noTSX</model>
</cpu>
关于内存的配置如下：
<domain>
...
<memory unit='KiB'>16777216</memory>
<currentMemory unit='KiB'>16777216</currentMemory>
...
</domain>
关于客户机类型和启动顺序配置如下：
<os>
<type arch='x86_64' machine='pc-i440fx-2.11'>hvm</type>
<boot dev='hd'/>
<boot dev='cdrom'/>
</os>
网络的配置
更新中…
