Keepalived+Nginx 高可用集群（双主模式）
环境准备
# systemctl stop firewalld //关闭防火墙
# sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/sysconfig/selinux //关闭selinux，重启生效
# setenforce 0 //关闭selinux，临时生效
# ntpdate 0.centos.pool.ntp.org //时间同步
# yum install nginx -y //安装nginx
echo "`hostname` `ifconfig ens33 |sed -n 's#.*inet \(.*\)netmask.*#\1#p'`" > /usr/share/nginx/html/index.html
//准备测试文件，此处是将主机名和ip写到index.html页面中
# vim /etc/nginx/nginx.conf //编辑配置文件
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
include /usr/share/nginx/modules/*.conf;
events {
worker_connections 1024;
}
http {
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
include /etc/nginx/conf.d/*.conf;
server {
listen 80;
server_name www.mtian.org;
location / {
root /usr/share/nginx/html;
}
access_log /var/log/nginx/access.log main;
}
}
# systemctl start nginx //启动nginx
# systemctl enable nginx //加入开机启动
配置LB服务器（两台都一样）
# vim /etc/nginx/nginx.conf
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
include /usr/share/nginx/modules/*.conf;
events {
worker_connections 1024;
}
http {
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
include /etc/nginx/conf.d/*.conf;
upstream backend {
server 192.168.1.33:80 weight=1 max_fails=3 fail_timeout=20s;
server 192.168.1.34:80 weight=1 max_fails=3 fail_timeout=20s;
}
server {
listen 80;
server_name www.mtian.org;
location / {
proxy_pass http://backend;
proxy_set_header Host $host:$proxy_port;
proxy_set_header X-Forwarded-For $remote_addr;
}
}
}
# systemctl start nginx //启动nginx
# systemctl enable nginx //加入开机自启动
在测试机（192.168.1.35）上面添加host解析，并测试lb集群是否正常。（测试机任意都可以，只要能访问lb节点。）
[root@node01 ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.32 www.mtian.org
192.168.1.31 www.mtian.org
// 测试时候轮流关闭lb1 和 lb2 节点，关闭后还是能够访问并看到轮循效果即表示 nginx lb集群搭建成功。
[root@node01 ~]# curl www.mtian.org
web01 192.168.1.33
[root@node01 ~]# curl www.mtian.org
web02 192.168.1.34
[root@node01 ~]# curl www.mtian.org
web01 192.168.1.33
[root@node01 ~]# curl www.mtian.org
web02 192.168.1.34
[root@node01 ~]# curl www.mtian.org
web01 192.168.1.33
[root@node01 ~]# curl www.mtian.org
web02 192.168.1.34
上面步骤成功后，开始搭建keepalived，在两台 lb节点上面安装keepalived（也可以源码编译安装、此处直接使用yum安装）
yum install keepalived -y
配置 LB-01节点
[root@LB-01 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
[email protected]
}
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state MASTER
interface ens33
virtual_router_id 51
priority 150
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.1.110/24 dev ens33 label ens33:1
}
}
[root@LB-01 ~]# systemctl start keepalived //启动keepalived
[root@LB-01 ~]# systemctl enable keepalived //加入开机自启动
[root@LB-01 ~]# ip a //查看IP，会发现多出了VIP 192.168.1.110
......
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:94:17:44 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.31/24 brd 192.168.1.255 scope global ens33
valid_lft forever preferred_lft forever
inet 192.168.1.110/24 scope global secondary ens33:1
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe94:1744/64 scope link
valid_lft forever preferred_lft forever
......
配置 LB-02节点
[root@LB-02 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
[email protected]
}
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state BACKUP
interface ens33
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.1.110/24 dev ens33 label ens33:1
}
}
[root@LB-02 ~]# systemctl start keepalived //启动keepalived
[root@LB-02 ~]# systemctl enable keepalived //加入开机自启动
[root@LB-02 ~]# ifconfig //查看IP，此时备节点不会有VIP（只有当主挂了的时候，VIP才会飘到备节点）
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.32 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::20c:29ff:feab:6532 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:ab:65:32 txqueuelen 1000 (Ethernet)
RX packets 43752 bytes 17739987 (16.9 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 4177 bytes 415805 (406.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
......
在测试机器上面访问 Keepalived上面配置的VIP 192.168.1.110
[root@node01 ~]# curl 192.168.1.110
web01 192.168.1.33
[root@node01 ~]# curl 192.168.1.110
web02 192.168.1.34
[root@node01 ~]# curl 192.168.1.110
web01 192.168.1.33
[root@node01 ~]# curl 192.168.1.110
web02 192.168.1.34
//关闭LB-01 节点上面keepalived主节点。再次访问
[root@LB-01 ~]# systemctl stop keepalived
[root@node01 ~]#
[root@node01 ~]# curl 192.168.1.110
web01 192.168.1.33
[root@node01 ~]# curl 192.168.1.110
web02 192.168.1.34
[root@node01 ~]# curl 192.168.1.110
web01 192.168.1.33
[root@node01 ~]# curl 192.168.1.110
web02 192.168.1.34
//此时查看LB-01 主节点上面的IP ，发现已经没有了 VIP
[root@LB-01 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.31 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::20c:29ff:fe94:1744 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:94:17:44 txqueuelen 1000 (Ethernet)
RX packets 46813 bytes 18033403 (17.1 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 9350 bytes 1040882 (1016.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
...
//查看LB-02 备节点上面的IP，发现 VIP已经成功飘过来了
[root@LB-02 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.32 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::20c:29ff:feab:6532 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:ab:65:32 txqueuelen 1000 (Ethernet)
RX packets 44023 bytes 17760070 (16.9 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 4333 bytes 430037 (419.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
ens33:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.110 netmask 255.255.255.0 broadcast 0.0.0.0
ether 00:0c:29:ab:65:32 txqueuelen 1000 (Ethernet)
...
说明：还是按照上面的环境继续做实验，只是修改LB节点上面的keepalived服务的配置文件即可。此时LB-01节点即为Keepalived的主节点也为备节点，LB-02节点同样即为Keepalived的主节点也为备节点。LB-01节点默认的主节点VIP（192.168.1.110），LB-02节点默认的主节点VIP（192.168.1.210）
1）配置 LB-01 节点
[root@LB-01 ~]# vim /etc/keepalived/keepalived.conf //编辑配置文件，增加一段新的vrrp_instance规则
! Configuration File for keepalived
global_defs {
notification_email {
[email protected]
}
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state MASTER
interface ens33
virtual_router_id 51
priority 150
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.1.110/24 dev ens33 label ens33:1
}
}
vrrp_instance VI_2 {
state BACKUP
interface ens33
virtual_router_id 52
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 2222
}
virtual_ipaddress {
192.168.1.210/24 dev ens33 label ens33:2
}
}
[root@LB-01 ~]# systemctl restart keepalived //重新启动keepalived
// 查看LB-01 节点的IP地址，发现VIP（192.168.1.110）同样还是默认在该节点
[root@LB-01 ~]# ip a
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:94:17:44 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.31/24 brd 192.168.1.255 scope global ens33
valid_lft forever preferred_lft forever
inet 192.168.1.110/24 scope global secondary ens33:1
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe94:1744/64 scope link
valid_lft forever preferred_lft forever
2）配置 LB-02 节点
[root@LB-02 ~]# vim /etc/keepalived/keepalived.conf //编辑配置文件，增加一段新的vrrp_instance规则
! Configuration File for keepalived
global_defs {
notification_email {
[email protected]
}
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state BACKUP
interface ens33
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.1.110/24 dev ens33 label ens33:1
}
}
vrrp_instance VI_2 {
state MASTER
interface ens33
virtual_router_id 52
priority 150
advert_int 1
authentication {
auth_type PASS
auth_pass 2222
}
virtual_ipaddress {
192.168.1.210/24 dev ens33 label ens33:2
}
}
[root@LB-02 ~]# systemctl restart keepalived //重新启动keepalived
// 查看LB-02节点IP，会发现也多了一个VIP（192.168.1.210），此时该节点也就是一个主了。
[root@LB-02 ~]# ip a
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:ab:65:32 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.32/24 brd 192.168.1.255 scope global ens33
valid_lft forever preferred_lft forever
inet 192.168.1.210/24 scope global secondary ens33:2
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:feab:6532/64 scope link
valid_lft forever preferred_lft forever
3）测试
[root@node01 ~]# curl 192.168.1.110
web01 192.168.1.33
[root@node01 ~]# curl 192.168.1.110
web02 192.168.1.34
[root@node01 ~]# curl 192.168.1.210
web01 192.168.1.33
[root@node01 ~]# curl 192.168.1.210
web02 192.168.1.34
测试可以发现我们访问keepalived中配置的两个VIP都可以正常调度等，当我们停止任意一台keepalived节点，同样还是正常访问；到此，keepalived+nginx高可用集群（双主模式）就搭建完成了。