Keepalived+Nginx 高可用集群（主從模式）
集群架構圖：
說明：Keepalived機器同樣是nginx負載均衡器。
1）實驗環境准備（此處都是使用的centos7系統）
# cat /etc/redhat-release CentOS Linux release 7.4.1708 (Core)
在所有節點上面進行配置
# systemctl stop firewalld //關閉防火牆 # sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/sysconfig/selinux //關閉selinux，重啟生效 # setenforce 0 //關閉selinux，臨時生效 # ntpdate 0.centos.pool.ntp.org //時間同步 # yum install nginx -y //安裝nginx
2）配置后端web服務器（兩台一樣）
# echo "`hostname` `ifconfig ens33 |sed -n 's#.*inet \(.*\)netmask.*#\1#p'`" > /usr/share/nginx/html/index.html //准備測試文件，此處是將主機名和ip寫到index.html頁面中
# vim /etc/nginx/nginx.conf //編輯配置文件 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 //啟動nginx # systemctl enable nginx //加入開機啟動
3）配置LB服務器（兩台都一樣）
# 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 //啟動nginx # systemctl enable nginx //加入開機自啟動
4）在測試機（192.168.1.35）上面添加host解析，並測試lb集群是否正常。（測試機任意都可以，只要能訪問lb節點。）
[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
// 測試時候輪流關閉lb1 和 lb2 節點，關閉后還是能夠訪問並看到輪循效果即表示 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
5）上面步驟成功后，開始搭建keepalived，在兩台 lb節點上面安裝keepalived（也可以源碼編譯安裝、此處直接使用yum安裝）
# yum install keepalived -y
6）配置 LB-01節點
[root@LB-01 ~]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { 381347268@qq.com } 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 //啟動keepalived [root@LB-01 ~]# systemctl enable keepalived //加入開機自啟動
[root@LB-01 ~]# ip a //查看IP，會發現多出了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 ......
7）配置 LB-02節點
[root@LB-02 ~]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { 381347268@qq.com } 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 //啟動keepalived [root@LB-02 ~]# systemctl enable keepalived //加入開機自啟動
[root@LB-02 ~]# ifconfig //查看IP，此時備節點不會有VIP（只有當主掛了的時候，VIP才會飄到備節點） 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 ......
8）在測試機器上面訪問 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
//關閉LB-01 節點上面keepalived主節點。再次訪問 [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
//此時查看LB-01 主節點上面的IP ，發現已經沒有了 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 備節點上面的IP，發現 VIP已經成功飄過來了 [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) ...
到此，Keepalived+Nginx高可用集群（主從）就搭建完成了。
Keepalived+Nginx 高可用集群（雙主模式）
將keepalived做成雙主模式，其實很簡單，就是再配置一段新的vrrp_instance（實例）規則，主上面加配置一個從的實例規則，從上面加配置一個主的實例規則。
集群架構圖：
說明：還是按照上面的環境繼續做實驗，只是修改LB節點上面的keepalived服務的配置文件即可。此時LB-01節點即為Keepalived的主節點也為備節點，LB-02節點同樣即為Keepalived的主節點也為備節點。LB-01節點默認的主節點VIP（192.168.1.110），LB-02節點默認的主節點VIP（192.168.1.210）
1）配置 LB-01 節點
[root@LB-01 ~]# vim /etc/keepalived/keepalived.conf //編輯配置文件，增加一段新的vrrp_instance規則 ! Configuration File for keepalived global_defs { notification_email { 381347268@qq.com } 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 //重新啟動keepalived
// 查看LB-01 節點的IP地址，發現VIP（192.168.1.110）同樣還是默認在該節點 [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 節點
[root@LB-02 ~]# vim /etc/keepalived/keepalived.conf //編輯配置文件，增加一段新的vrrp_instance規則 ! Configuration File for keepalived global_defs { notification_email { 381347268@qq.com } 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 //重新啟動keepalived
// 查看LB-02節點IP，會發現也多了一個VIP（192.168.1.210），此時該節點也就是一個主了。 [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）測試
[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
// 停止LB-01節點的keepalived再次測試 [root@LB-01 ~]# systemctl stop keepalived [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
測試可以發現我們訪問keepalived中配置的兩個VIP都可以正常調度等，當我們停止任意一台keepalived節點，同樣還是正常訪問；到此，keepalived+nginx高可用集群（雙主模式）就搭建完成了。