- 一、Keeplived简介
- 二、Keepalived工作原理
- 三.部署LVS+Keepalived 高可用群集
- 1、实验需求：
- 2.配置节点服务器1
- 节点服务器2
- 主负载调度器
- 负载调度器
一、Keeplived简介
专为LVS和HA设计的一款健康检查工具 支持故障自动切换（Failover） 支持节点健康状态检查（Health Checking）二、Keepalived工作原理
-
Keepalived是一个基于VRRP协议来实现的LVS服务高可用方案，可以解决静态路由出现的单点故障问题
-
在一个LVS服务集群中通常有主服（MASTER）和备份服务器（BACKUP）两种角色的服务器，但是对外表现为一个虚拟IP，主服务器会发送VRRP通告信息给备份服务器，当备份服务器收不到VRRP消息的时候，即主服务器异常的时候，备份服务器就会接管虚拟IP，继续提供服务，从而保证了高可用性
节点服务器1--------192.168.13.10 节点服务器2--------192.168.13.20 主负载调度器-------192.168.13.30 备负载调度器-------192.168.13.40
2.配置节点服务器1
（192.168.13.10）
[root@localhost ~]# systemctl stop firewalld.service
[root@localhost ~]# setenforce 0
setenforce: SELinux is disabled
[root@localhost ~]# yum install -y httpd
[root@localhost ~]# cd /etc/sysconfig/network-scripts/
[root@localhost network-scripts]# cp ifcfg-lo ifcfg-lo:0
[root@localhost network-scripts]# vim ifcfg-lo:0
内部配置： DEVICE=lo:0
IPADDR=192.168.13.100
NETMASK=255.255.255.255
ONBOOT=yes
[root@localhost network-scripts]# ifup lo:0 ##开启网卡
[root@localhost network-scripts]# route add -host 192.168.13.100 dev lo:0 ##vip地址需要通过虚网卡进入
##永久配置##
[root@localhost network-scripts]# vim /etc/rc.local
内部配置添加：
route add -host 192.168.13.100 dev lo:0
[root@localhost network-scripts]# chmod +x /etc/rc.d/rc.local ## 添加执行权限
[root@localhost network-scripts]# vim /etc/sysctl.conf
内部配置：
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
[root@localhost network-scripts]# sysctl -p ## 加载
net.ipv4.conf.lo.arp_ignore = 1 #系统只响应目的IP为本地IP的ARP请求
net.ipv4.conf.lo.arp_announce = 2 #系统不使用IP包的源地址来设置ARP
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
[root@localhost network-scripts]# cd /var/www/html/
[root@localhost html]# ls
[root@localhost html]# echo 'This is the first test web!' > index.html
[root@localhost html]# systemctl start httpd
[root@localhost ~]# yum install -y httpd
已加载插件：fastestmirror, langpacks
Loading mirror speeds from cached hostfile
正在解决依赖关系
--> 正在检查事务
---> 软件包 httpd.x86_64.0.2.4.6-88.el7.centos 将被 安装
--> 正在处理依赖关系 httpd-tools = 2.4.6-88.el7.centos，它被软件包 httpd-2.4.6-88.el7.centos.x86_64 需要
--> 正在处理依赖关系 /etc/mime.types，它被软件包 httpd-2.4.6-88.el7.centos.x86_64 需要
--> 正在检查事务
---> 软件包 httpd-tools.x86_64.0.2.4.6-88.el7.centos 将被 安装
---> 软件包 mailcap.noarch.0.2.1.41-2.el7 将被 安装
--> 解决依赖关系完成
.....
,,,,
.....
[root@localhost ~]# vim /etc/sysconfig/network-scripts/ifcfg-lo:0
内部：
DEVICE=lo:0
IPADDR=192.168.13.100
NETMASK=255.255.255.255
ONBOOT=yes
[root@localhost ~]# ifup lo:0
[root@localhost ~]# route add -host 192.168.13.100 dev lo:0
[root@localhost ~]# vim /etc/rc.local
[root@localhost ~]# chmod +x /etc/rc.d/rc.local
[root@localhost ~]# vim /etc/sysctl.conf
[root@localhost ~]# sysctl -p
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
[root@localhost ~]# cd /var/www/html/
[root@localhost html]# echo 'This is the second test web!' > index.html
[root@localhost html]# systemctl start httpd
主负载调度器
[root@localhost ~]# cd /etc/keepalived
[root@localhost keepalived]# cp keepalived.conf keepalived.conf.bak
###复制配置文件####
[root@localhost keepalived]# vim keepalived.conf
:set nu ##打开行号
smtp_server 127.0.0.1 ## 第10行：邮箱地址改成本地ip
router_id LVS_01 ### 第12行：区分路由名称 改成01
###### 下面4行 全部删掉 ######
###### vrrp 热备份实例配置#######
interface ens33 ## 第17行：第一张网卡名称
priority 100 这行的上方添加：nopreempt ### 非抢占模式
192.168.58.100 ## 第27行：VIP地址 后面的两行多余ip删掉
######### 虚拟服务器 ###########
192.168.58.100 80 ## 第31行：虚拟IP地址为VIP地址，80端口为http协议
lb_kind DR ## 第34行：LVS工作模式为DR
persistence_timeout 0 ### 第35行：长连接超时时间，单位秒
protocol TCP ### 第36行：健康检查协议为tcp
192.168.58.15 80 #### 第38行：真实节点服务器的ip地址，80号端口
##### 下面为健康检查方式：########
TCP_CHECK { #### 第40行 ：端口检查的方式
connect_port 80 #### 通过tcp协议 检查80号端口
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
########## 后面的不需要一直删到第一个 "}" 为止
:38,46 co 46 #### 末行模式 复制另外一台节点服务器配置
记得将真实节点服务器ip地址改一下
100 dd ###### 在第58行 删除后面不需要的虚拟服务器配置
[root@localhost keepalived]# systemctl start keepalived
[root@localhost keepalived]# ip addr
### 查看相关配置
1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
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: ens33: mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:0c:29:c7:ea:82 brd ff:ff:ff:ff:ff:ff
inet 192.168.13.30/24 brd 192.168.13.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fec7:ea82/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: virbr0: mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether 52:54:00:83:ff:e2 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
link/ether 52:54:00:83:ff:e2 brd ff:ff:ff:ff:ff:ff
[root@localhost keepalived]# scp keepalived.conf 192.168.13.30:`pwd` #远程传输文件到备负载调度器
The authenticity of host '192.168.13.30 (192.168.13.30)' can't be established.
ECDSA key fingerprint is SHA256:ka7ipT8mDX2Z2IxR+3inYCB+HuVmU+rIV5UU/HErCbQ.
ECDSA key fingerprint is MD5:8d:27:22:9b:97:78:5a:0a:dd:c8:2e:66:44:9a:64:57.
Are you sure you want to continue connecting (yes/no)? YES
Warning: Permanently added '192.168.13.30' (ECDSA) to the list of known hosts.
root@192.168.13.30's password:
keepalived.conf 100% 1281 3.3MB/s 00:00
[root@localhost keepalived]# ipvsadm-save > /etc/sysconfig/ipvsadm
[root@localhost keepalived]# systemctl start ipvsadm
[root@localhost keepalived]# systemctl restart keepalived
[root@localhost keepalived]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
[root@localhost ~]# cd /etc/keepalived/
[root@localhost keepalived]# vim keepalived.conf
router_id LVS_02
state BACKUP
priority 90
[root@localhost keepalived]# systemctl start keepalived
[root@localhost keepalived]# ipvsadm-save > /etc/sysconfig/ipvsadm
[root@localhost keepalived]# systemctl start ipvsadm
[root@localhost keepalived]# systemctl restart keepalived
[root@localhost keepalived]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
