- [1. keepalived 簡介 ##](#1-keepalived-簡介-)
        - [1. keepalived](#1-keepalived)
        - [2. 安裝keepalived](#2-安裝keepalived)
- [2. keepalived 高可用配置 ##](#2-keepalived-高可用配置-)
        - [1. 安裝keepalived](#1-安裝keepalived)
        - [2. 配置keepalived以實現虛擬IP繫結](#2-配置keepalived以實現虛擬ip繫結)

1. keepalived 簡介

1. keepalived

Keepalived的作用是檢測伺服器的狀態，如果有一臺web伺服器宕機，或工作出現故障，Keepalived將檢測到，並將有故障的伺服器從系統中剔除，同時使用其他伺服器代替該伺服器的工作，當伺服器工作正常後Keepalived自動將伺服器加入到伺服器群中，這些工作全部自動完成，不需要人工干涉，需要人工做的只是修復故障的伺服器。

2. 安裝keepalived

Centos7 預設的keepalived版本有問題，直接原始碼編譯安裝
這裡下載的keepadlived版本為2.0.7
首先安裝依賴檔案(兩臺機器)

# yum install -y gcc gcc-c++  openssl-devel
 

然後執行編譯安裝(兩臺機器)

# tar xvf keepalived-2.0.7.tar
# cd keepalived-2.0.7
# ./configure
# make
# make install

複製配置檔案(兩臺機器)

# mkdir /etc/keepalived
# cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf

2. keepalived 高可用配置

這裡的兩臺伺服器使用keepalived執行虛擬IP的動態切換，具體要求如下：

1. 安裝keepalived

首先兩臺伺服器均要按照上一節描述的方法來進行Keepalived的安裝

2. 配置keepalived以實現虛擬IP繫結

修改配置檔案:/etc/keepalived/keepalived.conf(主)

1 ! Configuration File for keepalived
2
3 global_defs {
4    router_id master
5 }
6
7 vrrp_instance VI_1 {
8     state MASTER
9     interface em2
10     virtual_router_id 52
11     priority 100
12     advert_int 1
13     authentication {
14         auth_type PASS
15         auth_pass 1111
16     }
17     virtual_ipaddress {
18         172.16.0.8/24
19     }
20 }
21
22 virtual_server 192.168.200.100 443 {

注： 檔案其他部分不動

修改配置檔案:/etc/keepalived/keepalived.conf(備)

1 ! Configuration File for keepalived
2
3 global_defs {
4    router_id backup
5 }
6
7 vrrp_instance VI_1 {
8     state BACKUP
9     interface em2
10     virtual_router_id 52
11     priority 90
12     advert_int 1
13     authentication {
14         auth_type PASS
15         auth_pass 1111
16     }
17     virtual_ipaddress {
18         172.16.0.8/24
19     }
20 }
21
22 virtual_server 192.168.200.100 443 {

注： 檔案其他部分不動

兩機器都設定服務啟動，並通過ps檢視程序是否執行

# systemctl start keepalived
# systemctl enable keepalived

然後通過 ip a 來檢視虛擬IP是否繫結成功

# ip a