update

develop/keepalived.md

@@ -1,5 +1,8 @@
 ## keepalived
 
+VRRP 是Virtual Router Redundancy Protocol(虚拟路由冗余协议)的缩写, VRRP协议将两台或多台路由器设备虚拟成一个设
+备, 对外提供虚拟路由器IP(一个或多个).
+
 双机高可用的两种模式:
 
 - 主从模式: 一台主服务器, 一台热备服务器, 正常情况下, 主服务器绑定公网虚拟IP, 提供负载均衡服务, 热备服务器处于空闲状
@@ -10,14 +13,89 @@
 台发生故障时, 另外一台接管发生故障服务服务器的公网虚拟IP(此时活动的机器承担所有请求)
 
 
-主从:
+### 主从配置
+
+vip: 192.168.200.100
+
+// master config
+```
+// master
+global_defs {
+    router_id master       
+}
+
+# check nginx runing
+vrrp_script chk_nginx {
+    script "/etc/keepalived/nginx_check.sh"
+    interval 2
+    weight -20
+}
+
+vrrp_instance VI_1 {
+    state MASTER   
+    interface eth0
+    virtual_router_id 50
+    nopreempt
+    priority 100
+    advert_int 1
+    virtual_ipaddress {
+        192.168.200.100
+    }
+    track_script {
+        chk_nginx
+    }
+}
+```
+
+// backup config
+```
+// backup
+global_defs {
+    router_id backup       
+}
+
+# check nginx runing
+vrrp_script chk_nginx {
+    script "/etc/keepalived/nginx_check.sh"
+    interval 2
+    weight -20
+}
+
+vrrp_instance VI_1 {
+    state BACKUP   
+    interface eth0
+    virtual_router_id 50
+    nopreempt
+    priority 80
+    advert_int 1
+    virtual_ipaddress {
+        192.168.200.100
+    }
+    track_script {
+        chk_nginx
+    }
+}
+```
+
+### 主从配置升级到双主配置
+
+vip1: 192.168.200.100
+vip2: 192.168.200.200
 
+// one
 ```
 // master
 global_defs {
     router_id master       
 }
 
+# check nginx runing
+vrrp_script chk_nginx {
+    script "/etc/keepalived/nginx_check.sh"
+    interval 2
+    weight -20
+}
+
 vrrp_instance VI_1 {
     state MASTER   
     interface eth0
@@ -26,16 +104,43 @@ vrrp_instance VI_1 {
     priority 100
     advert_int 1
     virtual_ipaddress {
-        192.168.200.11
+        192.168.200.100
+    }
+    track_script {
+        chk_nginx
     }
 }
 
+vrrp_instance VI_2 {
+    state BACKUP   
+    interface eth0
+    virtual_router_id 51
+    nopreempt
+    priority 80
+    advert_int 1
+    virtual_ipaddress {
+        192.168.200.200
+    }
+    track_script {
+        chk_nginx
+    }
+}
+```
 
+// another
+```
 // backup
 global_defs {
     router_id backup       
 }
 
+# check nginx runing
+vrrp_script chk_nginx {
+    script "/etc/keepalived/nginx_check.sh"
+    interval 2
+    weight -20
+}
+
 vrrp_instance VI_1 {
     state BACKUP   
     interface eth0
@@ -44,7 +149,25 @@ vrrp_instance VI_1 {
     priority 80
     advert_int 1
     virtual_ipaddress {
-        192.168.200.11
+        192.168.200.100
+    }
+    track_script {
+        chk_nginx
+    }
+}
+
+vrrp_instance VI_2 {
+    state MASTER
+    interface eth0
+    virtual_router_id 51
+    nopreempt
+    priority 100
+    advert_int 1
+    virtual_ipaddress {
+        192.168.200.200
+    }
+    track_script {
+        chk_nginx
     }
 }
 ```