虚拟化

一.虚拟化介绍
指通过虚拟化技术将一台计算机虚拟为多台逻辑计算机。在一台计算机上同时运行多个逻辑计算机，每个逻辑计算机可运行不同的操作系统，并且应用程序都可以在相互独立的空间内运行而互不影响，从而显著提高计算机的工作效率
二. 虚拟化分类
虚拟化技术可分为：全虚拟化和半虚拟化。

三. 虚拟化架构

Hypervisor直接安装在物理机上，多个虚拟机在 Hypervisor 上运行。Hypervisor 实现方式一般是一个特殊定制的Linux系统。Xen和VMWare的ESXi 都属于这个类型。

四.常见的虚拟化软件

查看内存是否更改成功

[root@localhost ~]# free
              total        used        free      shared 
Mem:        1868684      106272     1460848        8800 
Swap:       2097148           0     2097148

检查CPU是否开启虚拟化支持

[root@localhost ~]# cat /proc/cpuinfo |grep vmx
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch arat tpr_shadow vnmi ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid avx512f rdseed adx smap clflushopt avx512cd xsaveopt xsavec xsaves
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch arat tpr_shadow vnmi ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid avx512f rdseed adx smap clflushopt avx512cd xsaveopt xsavec xsaves

格式化

[root@kvm ~]# mkfs.ext4 /dev/sdb
mke2fs 1.42.9 (28-Dec-2013)
/dev/sdb is entire device, not just one partition!
Proceed anyway? (y,n) y
Discarding device blocks:  3149824/13107200
Message from syslogd@localhost at Mar  9 22:40:48 ...
 kernel:BUG: soft lockup - CPU#0 stuck for 50s! [systemd
done                            
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
3276800 inodes, 13107200 blocks
655360 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2162163712
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, 88
	4096000, 7962624, 11239424

Allocating group tables: done                           
Writing inode tables: done                            
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting informatio

查看格式化是否成功

[root@kvm ~]# blkid /dev/sdb
/dev/sdb: UUID="f7b72c5a-c68f-457c-a40c-f547d1552f4a" TYPE="ext4" 

挂载

[root@kvm ~]# mkdir /kvm_data
[root@kvm ~]# mount /dev/sdb /kvm_data/
[root@kvm ~]# vi /etc/fstab

关闭防火墙并设置开机不自启

[root@kvm ~]# systemctl stop firewalld
[root@kvm ~]# systemctl disable firewalld
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
Removed symlink /etc/systemd/system/basic.target.wants/firewalld.service.

查看是否清楚规则

[root@kvm ~]# iptables -nvL
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         

[root@kvm ~]# getenforce 0
Enforcing
[root@kvm ~]# setenforce 0
[root@kvm ~]# getenforce 
Permissive

安装

[root@kvm ~]# yum install -y virt-* libvirt bridge-utils qemu-img

[root@kvm ~]# cd /etc/sysconfig/network-scripts/

[root@kvm network-scripts]# cp ifcfg-eno16777728 ifcfg-br0

编辑配置文件

[root@kvm network-scripts]#vi ifcfg-br0

[root@kvm network-scripts]# vi ifcfg-eno16777728 

重启网卡

[root@kvm network-scripts]# service network restart 
Restarting network (via systemctl):                  [  OK  ]

桥接到br0

[root@kvm network-scripts]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eno16777728: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UP qlen 1000
    link/ether 00:50:56:a0:85:73 brd ff:ff:ff:ff:ff:ff
3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP 
    link/ether 00:50:56:a0:85:73 brd ff:ff:ff:ff:ff:ff
    inet 10.30.59.218/25 brd 10.30.59.255 scope global br0
       valid_lft forever preferred_lft forever
    inet6 fe80::2050:70ff:fe91:1bad/64 scope link 
       valid_lft forever preferred_lft forever

启动服务

[root@kvm network-scripts]# systemctl start libvirtd

查看进程

[root@kvm network-scripts]# ps -ef |grep libvirt
root      31126      1  0 00:04 ?        00:00:00 /usr/sbin/libvirtd
nobody    31226      1  0 00:04 ?        00:00:00 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
root      31227  31226  0 00:04 ?        00:00:00 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
root      31279  17971  0 00:07 pts/0    00:00:00 grep --color=auto libvirt

br0就是桥接模式
virbr0就是nat模式