Nginx 配置高可用集群
Nginx的高可用集群是指由两台或多台Nginx服务器组成的集群系统，通过负载均衡和故障转移等技术，实现高可用性和可伸缩性的目标。在这种集群系统中，每个Nginx服务器都配置为主节点（master）或从节点（slave）。主节点负责处理业务逻辑，而从节点则通过心跳检查等方式与主节点保持通信，并随时准备接管业务逻辑。当主节点出现故障时，从节点会通过心跳检查机制检测到，并立即接管主节点的业务逻辑，从而保证服务的连续性和可用性。这种集群系统可以有效解决单点故障的问题，提高系统的可用性和稳定性。在配置Nginx的高可用集群时，需要考虑到负载均衡、故障转移、状态监控等多个方面，以保证系统的正常运行和可靠性。同时，也需要对每个服务器的硬件配置、网络环境、负载情况等进行合理的规划和调整，以保证整个集群的性能和效率。
1、准备
需要两台服务器
server 172.31.0.99;server 172.31.0.100;
1.1在两台服务器安装 nginx
安装详情见 nginx学习(1)： 链接: link
1.2第一台用默认的配置80端口，第二台用81端口
server {listen 80; #server_name localhost;server_name 172.31.0.99 ;#charset koi8-r;#access_log logs/host.access.log main;location / {root html;#proxy_pass http://myserver;index index.html index.htm;}
server {listen 81; #server_name localhost;server_name 172.31.0.100 ;#charset koi8-r;#access_log logs/host.access.log main;location / {root html;#proxy_pass http://myserver;index index.html index.htm;}
测试：
http://172.31.0.99/
http://172.31.0.100:81/
2、安装keepalived
在两台服务器安装keepalived
yum install keepalived -y
# 查看版本：
rpm -q -a keepalived
主服务器配置：
! Configuration File for keepalivedglobal_defs {notification_email {acassen@firewall.locfailover@firewall.locsysadmin@firewall.loc}notification_email_from Alexandre.Cassen@firewall.locsmtp_server 192.168.200.1smtp_connect_timeout 30router_id LVS_DEVELvrrp_skip_check_adv_addrvrrp_strictvrrp_garp_interval 0vrrp_gna_interval 0
}vrrp_script chk_http_port {script "/usr/local/src/nginx_check.sh"interval 2 #（检测脚本执行的间隔）weight 2
}vrrp_instance VI_1 {state MASTER # 备份服务器上将 MASTER 改为 BACKUP interface ens33 //网卡virtual_router_id 51 # 主、备机的 virtual_router_id 必须相同priority 100 # 主、备机取不同的优先级，主机值较大，备份机值较小advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {192.168.19.50 # VRRP H 虚拟地址（非真实物理地址）} #vrrp_instance VI_1 {
# state MASTER
# interface eth0
# virtual_router_id 51
# priority 100
# advert_int 1
# authentication {
# auth_type PASS
# auth_pass 1111
# }
# virtual_ipaddress {
# 192.168.200.16
# 192.168.200.17
# 192.168.200.18
# }
#}virtual_server 192.168.200.100 443 {delay_loop 6lb_algo rrlb_kind NATpersistence_timeout 50protocol TCPreal_server 192.168.201.100 443 {weight 1SSL_GET {url {path /digest ff20ad2481f97b1754ef3e12ecd3a9cc}url {path /mrtg/digest 9b3a0c85a887a256d6939da88aabd8cd}connect_timeout 3nb_get_retry 3delay_before_retry 3}}
}virtual_server 10.10.10.2 1358 {delay_loop 6lb_algo rr lb_kind NATpersistence_timeout 50protocol TCPsorry_server 192.168.200.200 1358real_server 192.168.200.2 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl3/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}connect_timeout 3nb_get_retry 3delay_before_retry 3}}real_server 192.168.200.3 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334c}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334c}connect_timeout 3nb_get_retry 3delay_before_retry 3}}
}virtual_server 10.10.10.3 1358 {delay_loop 3lb_algo rr lb_kind NATpersistence_timeout 50protocol TCPreal_server 192.168.200.4 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl3/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}connect_timeout 3nb_get_retry 3delay_before_retry 3}}real_server 192.168.200.5 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl3/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}connect_timeout 3nb_get_retry 3delay_before_retry 3}}
}从服务器配置：
! Configuration File for keepalivedglobal_defs {notification_email {acassen@firewall.locfailover@firewall.locsysadmin@firewall.loc}notification_email_from Alexandre.Cassen@firewall.locsmtp_server 192.168.200.1smtp_connect_timeout 30router_id LVS_DEVELvrrp_skip_check_adv_addrvrrp_strictvrrp_garp_interval 0vrrp_gna_interval 0
}vrrp_script chk_http_port {script "/usr/local/src/nginx_check.sh"interval 2 #（检测脚本执行的间隔）weight 2}vrrp_instance VI_1 {state BACKUP # 备份服务器上将 MASTER 改为 BACKUP interface ens33 //网卡virtual_router_id 51 # 主、备机的 virtual_router_id 必须相同priority 90 # 主、备机取不同的优先级，主机值较大，备份机值较小advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {192.168.19.50 # VRRP H 虚拟地址（非真实物理地址）}
}#vrrp_instance VI_1 {
# state MASTER
# interface eth0
# virtual_router_id 51
# priority 100
# advert_int 1
# authentication {
# auth_type PASS
# auth_pass 1111
# }
# virtual_ipaddress {
# 192.168.200.16
# 192.168.200.17
# 192.168.200.18
# }
#}virtual_server 192.168.200.100 443 {delay_loop 6lb_algo rrlb_kind NATpersistence_timeout 50protocol TCPreal_server 192.168.201.100 443 {weight 1SSL_GET {url {path /digest ff20ad2481f97b1754ef3e12ecd3a9cc}url {path /mrtg/digest 9b3a0c85a887a256d6939da88aabd8cd}connect_timeout 3nb_get_retry 3delay_before_retry 3}}
}virtual_server 10.10.10.2 1358 {delay_loop 6lb_algo rr lb_kind NATpersistence_timeout 50protocol TCPsorry_server 192.168.200.200 1358real_server 192.168.200.2 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl3/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}connect_timeout 3nb_get_retry 3delay_before_retry 3}}real_server 192.168.200.3 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334c}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334c}connect_timeout 3nb_get_retry 3delay_before_retry 3}}
}virtual_server 10.10.10.3 1358 {delay_loop 3lb_algo rr lb_kind NATpersistence_timeout 50protocol TCPreal_server 192.168.200.4 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl3/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}connect_timeout 3nb_get_retry 3delay_before_retry 3}}real_server 192.168.200.5 1358 {weight 1HTTP_GET {url { path /testurl/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl2/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}url { path /testurl3/test.jspdigest 640205b7b0fc66c1ea91c463fac6334d}connect_timeout 3nb_get_retry 3delay_before_retry 3}}
}接着重启nginx，启动keepalived
（主服务器：）
接着重启nginx，启动keepalived
（从服务器：）
3、访问测试：
1、使用 ip a 查看主服务器的虚拟IP，进行访问
http://172.31.0.152/，成功访问！
成功访问！
1、使用 ip a 查看从服务器的虚拟IP，进行访问
http://172.31.0.151:81/
成功访问！
