A example from keepalived document

+# Configuration File for keepalived
+global_defs {
+    notification_email {
+        admin@domain.com
+        0633225522@domain.com
+    }
+    notification_email_from keepalived@domain.com
+    smtp_server 192.168.200.20
+    smtp_connect_timeout 30
+    router_id LVS_MAIN
+}
+
+# VRRP Instances definitions
+vrrp_instance VI_1 {
+    state MASTER
+    interface eth0
+    virtual_router_id 51
+    priority 150
+    advert_int 1
+    authentication {
+        auth_type PASS
+        auth_pass k@l!ve1
+    }
+    virtual_ipaddress {
+        192.168.200.10
+        192.168.200.11
+    }
+}
+vrrp_instance VI_2 {
+    state MASTER
+    interface eth1
+    virtual_router_id 52
+    priority 150
+    advert_int 1
+    authentication {
+        auth_type PASS
+        auth_pass k@l!ve2
+    }
+    virtual_ipaddress {
+        192.168.100.10
+    }
+}
+vrrp_instance VI_3 {
+    state BACKUP
+    interface eth0
+    virtual_router_id 53
+    priority 100
+    advert_int 1
+    authentication {
+        auth_type PASS
+        auth_pass k@l!ve3
+    }
+    virtual_ipaddress {
+        192.168.200.12
+        192.168.200.13
+    }
+}
+vrrp_instance VI_4 {
+    state BACKUP
+    interface eth1
+    virtual_router_id 54
+    priority 100
+    advert_int 1
+    authentication {
+        auth_type PASS
+        auth_pass k@l!ve4
+    }
+    virtual_ipaddress {
+        192.168.100.11
+    }
+}
+# Virtual Servers definitions
+virtual_server 192.168.200.10 80 {
+    delay_loop 30
+    lb_algo wrr
+    lb_kind NAT
+    persistence_timeout 50
+    protocol TCP
+    sorry_server 192.168.100.100 80
+    real_server 192.168.100.2 80 {
+        weight 2
+        HTTP_GET {
+            url {
+                path /testurl/test.jsp
+                digest ec90a42b99ea9a2f5ecbe213ac9eba03
+            }
+            url {
+                path /testurl2/test.jsp
+                digest 640205b7b0fc66c1ea91c463fac6334c
+            }
+            connect_timeout 3
+            retry 3
+            delay_before_retry 2
+        }
+    }
+    real_server 192.168.100.3 80 {
+        weight 1
+        HTTP_GET {
+            url {
+                path /testurl/test.jsp
+                digest 640205b7b0fc66c1ea91c463fac6334c
+            }
+            connect_timeout 3
+            retry 3
+            delay_before_retry 2
+        }
+    }
+}
+virtual_server 192.168.200.12 443 {
+    delay_loop 20
+    lb_algo rr
+    lb_kind NAT
+    persistence_timeout 360
+    protocol TCP
+    real_server 192.168.100.2 443 {
+        weight 1
+        TCP_CHECK {
+            connect_timeout 3
+        }
+    }
+    real_server 192.168.100.3 443 {
+        weight 1
+        TCP_CHECK {
+            connect_timeout 3
+        }
+    }
+}
+

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