nginx + keepalived 雙機熱備

時間 2019-11-19

原文原文鏈接

序

雙機熱備是指兩臺機器都在運行，但並不是兩臺機器同時在提供服務。
當提供服務的一臺出現故障的時候，另一臺會立刻自動接管而且提供服務，且切換的時間很是短。html

keepalived的工做原理是VRRP——虛擬路由冗餘協議。node

測試環境以下：nginx

	ip瀏覽器	vipbash
master網絡	192.168.174.135app	192.168.174.140tcp
backupoop	192.168.174.137測試	192.168.174.140

nginx

安裝

sudo apt-get install nginx

查找配置文件位置

sudo find / -name nginx.conf
/etc/nginx/nginx.conf

修改配置文件（nginx.conf）

user www-data;
worker_processes 4;
pid /run/nginx.pid;

events {
    worker_connections 1024;
}

http {
    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;

    access_log /var/log/nginx/access.log;
    error_log /var/log/nginx/error.log;

    server {
        listen 80 default_server;
        server_name test;
        charset utf-8;

        location / {
        root html;
        index index.html index.htm;
        proxy_set_header X-Real_IP $remote_addr;
        client_max_body_size 100m;
        }
    }
}

文件/usr/share/nginx/html/index.html

在192.168.174.135上加上 <h1>Welcome to nginx! 135 </h1>

在192.168.174.137上加上 <h1>Welcome to nginx! ***137*** </h1>

啓動

sudo service nginx start

關閉

sudo service nginx stop

keepalived

安裝

下載keepalived-1.2.19.tar.gz

tar –zxvf keepalived-1.2.19.tar.gz
cd keepalived-1.2.19
./configure --prefix=/usr/local/keepalived
make
sudo make install

期間可能出現問題：

!!! OpenSSL is not properly installed on your system. !!!
!!! Can not include OpenSSL headers files. !!!

解決

sudo apt-get install libssl.dev

創建軟連接

sudo ln -s /usr/local/keepalived/sbin/keepalived /sbin/
sudo ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
sudo ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/

啓動

sudo keepalived -D -f /usr/local/keepalived/etc/keepalived/keepalived.conf

關閉

sudo killall keepalived

配置（keepalived.conf）：

global_defs {
    router_id NODEA
}

vrrp_instance VI_1 {
    state MASTER 
    interface eth0        #監測網絡接口 
    virtual_router_id 50  #主、備必須同樣  
    priority 100          #優先級：主＞備
    advert_int 1
    authentication {
        auth_type PASS #VRRP認證，主備一致
        auth_pass 1111  #密碼
}

virtual_ipaddress {
        192.168.174.140/24 #VRRP HA虛擬地址
    }
}

備用節點的配置

global_defs {
   router_id NODEB
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 50
    priority 90 
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }

 virtual_ipaddress {
    192.168.174.140/24
    }
}

測試

雙擊熱備

兩臺機子均啓動nginx和keepalived，瀏覽器各自訪問

瀏覽器訪問：http://192.168.174.140/，顯示的是MASTER的頁面。

一樣用ip appr能夠驗證：

135機器：

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default

link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

inet 127.0.0.1/8 scope host lo