Nginx+keepalived Dual main polling load balancing

The dual main mode uses two VIP, the front section has 2 servers, the main from each other, two servers working simultaneously, there is no waste of resources. At the same time in the front-end DNS server to the site long a record, to achieve the load balancing Nginx, when a server failure, the resources will be transferred to another server, continue to provide services, most of the large-scale Web site Use this kind of architecture. The high availability of the nginx+keepalived is configured here using the main main mode.

Two nginx, two web, front-end DNS provided by the operator.

IP Address

nginx1:10.10.10.11

nginx2:10.10.10.12

vip1:10.10.10.21

vip2:10.10.10.22

real1:10.10.10.13

real2:10.10.10.14

1, deploy the environment on 2 web hosts, install Nginx+php+mysql, refer to my previous article

2, respectively, in two Nginx load balancer installed Nginx, configuration

Install the GCC compiler and other tools:

Yum install-y gcc gcc-c++ autoconf automake libtool make OpenSSL openssl-devel

Install Nginx:

wget http://exim.mirror.fr/pcre/pcre-8.38.tar.gz

TAR-ZXVF pcre-8.38.tar.gz

CD pcre-8.38

./configure

Make && make install

wget http://zlib.net/zlib-1.2.8.tar.gz

TAR-ZXVF zlib-1.2.8.tar.gz

CD zlib-1.2.8

./configure

Make && make install

wget http://nginx.org/download/nginx-1.6.3.tar.gz

TAR-ZXVF nginx-1.6.3.tar.gz

CD nginx-1.6.3/

./configure--prefix=/usr/local/nginx--sbin-path=/usr/local/nginx/sbin/nginx--conf-path=/usr/local/nginx/conf/ nginx.conf--pid-path=/usr/local/nginx/logs/nginx.pid--with-http_ssl_module--with-http_stub_status_module-- With-http_gzip_static_module

Make && make install

nginx.conf config file, same as two nginx load balancer files

User nobody;

Worker_processes 1;

Error_log/usr/local/nginx/logs/error.log notice;

Pid/usr/local/nginx/logs/nginx.pid;

Worker_rlimit_nofile 51200;

Events {

Use Epoll;

Worker_connections 51200;

}

HTTP {

Include Mime.types;

Default_type Application/octet-stream;

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 Logs/access.log Main;

Server_names_hash_bucket_size 128;

Client_header_buffer_size 32k;

Large_client_header_buffers 4 32k;

Client_max_body_size 8m;

Sendfile on;

Tcp_nopush on;

Server_tokens off;

Keepalive_timeout 60;

Fastcgi_connect_timeout 300;

Fastcgi_send_timeout 300;

Fastcgi_read_timeout 300;

Fastcgi_buffer_size 64k;

Fastcgi_buffers 4 64k;

Fastcgi_busy_buffers_size 128k;

Fastcgi_temp_file_write_size 128k;

gzip on;

Upstream Backend

{

Server 10.10.10.13;

Server 10.10.10.14;

}

server {

Listen 80;

server_name 10.10.10.21; #Nginx2改为10.10.10.22

Location/{

root HTML;

Index index.php index.html index.htm;

Proxy_redirect off;

Proxy_set_header Host $host;

Proxy_set_header X-real-ip $remote _addr;

#后端的Web服务器可以通过X-forwarded-for Get the user real IP

Proxy_set_header x-forwarded-for $proxy _add_x_forwarded_for;

Proxy_pass Http://backend;

}

Error_page 502 503 504/50x.html;

Location =/50x.html {

root HTML;

}

Location/nginx_status {

Stub_status on;

Auth_basic "Nginxstatus";

AUTH_BASIC_USER_FILE/USR/LOCAL/NGINX/HTPASSWD;

#allow 127.0.0.1;

#deny all;

}

Location ~* \. (ini|docx|txt|doc|pdf) $ {

#禁止访问文档性文件

root/usr/share/nginx/html;

Deny all;

}

Location ~. *\. (GIF|JPG|JPEG|PNG|BMP|SWF|JS|HTML|HTM|CSS) $ {

Root/home/image;

Proxy_store on;

Proxy_store_access USER:RW GROUP:RW ALL:RW;

Proxy_temp_path/home/image;

if (!-e $request _filename) {

Proxy_pass Http://backend;

}

}

}

}

Configuration Complete Start Service

[Email protected] sbin]#./nginx

./nginx:error while loading shared libraries:libpcre.so.1:cannot open Shared object file:no such file or directory

Cd/lib

[[email protected] lib]# ls

[[email protected] lib]# ls *pcre*

libpcre.so.0 libpcre.so.0.0.1

[Email protected] lib]# ln-s/lib/libpcre.so.0.0.1/lib/libpcre.so.1

[Email protected] lib]#

[Email protected] sbin]#./nginx

Install and configure the keepalived on the two Nginx devices:

wget http://www.keepalived.org/software/keepalived-1.2.15.tar.gz

TAR-ZXVF keepalived-1.2.15.tar.gz

CD keepalived-1.2.15

./configure--sysconf=/etc/--with-kernel-dir=/usr/src/kernels/2.6.32-358.el6.i686

keepalived Configuration

------------------------

Keepalived version:1.2.15

compiler:gcc

Compiler Flags:-G-O2

Extra Lib:-lssl-lcrypto-lcrypt

Use IPVS Framework:yes

IPVS Sync Daemon Support:yes

IPVS Use Libnl:no

Fwmark Socket Support:yes

Use VRRP Framework:yes

Use VRRP Vmac:yes

SNMP Support:no

SHA1 Support:no

Use Debug Flags:no

Make && make install

Ln-s/usr/local/sbin/keepalived/sbin/

#这一步很重要, do not execute Ln-s will error "Starting keepalived:/bin/bash:keepalived:command not Found"

Service keepalived Start

Two nginx on the keepalived.conf configuration as follows, after the configuration is completed, respectively service keepalived start, detection keepalived configuration is successful

NGINX1:

Global_defs {

Notification_email {

[Email protected]

}

Notification_email_from [email protected]

Smtp_server 127.0.0.1

Smtp_connect_timeout 30

router_id Nginx_vip1

}

Vrrp_script Chk_http_port {

Script "/usr/local/src/check_nginx_pid.sh"

Interval 2 # (detects the interval of script execution)

Weight 2

}

Vrrp_instance Vi_1 {

State MASTER

Interface eth1

VIRTUAL_ROUTER_ID 51

Priority 100

Advert_int 1

Authentication {

Auth_type PASS

Auth_pass 1111

}

Track_script {

Chk_http_port # (Invoke detection script)

}

virtual_ipaddress {

10.10.10.21/24 broadcast 10.10.10.255 Dev eth1 label eth1:1

}

}

Vrrp_instance Vi_2 {

State BACKUP

Interface eth1

VIRTUAL_ROUTER_ID 52

Priority 99

Advert_int 1

Authentication {

Auth_type PASS

Auth_pass 1111

}

Track_script {

Chk_http_port # (Invoke detection script)

}

virtual_ipaddress {

10.10.10.22/24 broadcast 10.10.10.255 Dev eth1 label Eth1:2

}

}

NGINX2:

Global_defs {

Notification_email {

[Email protected]

}

Notification_email_from [email protected]

Smtp_server 127.0.0.1

Smtp_connect_timeout 30

router_id NGINX_VIP2

}

Vrrp_script Chk_http_port {

Script "/usr/local/src/check_nginx_pid.sh"

Interval 2 # (detects the interval of script execution)

Weight 2

}

Vrrp_instance Vi_1 {

State BACKUP

Interface eth1

VIRTUAL_ROUTER_ID 51

Priority 99

Advert_int 1

Authentication {

Auth_type PASS

Auth_pass 1111

}

Track_script {

Chk_http_port # (Invoke detection script)

}

virtual_ipaddress {

10.10.10.21/24 broadcast 10.10.10.255 Dev eth1 label eth1:1

}

}

Vrrp_instance Vi_2 {

State MASTER

Interface eth1

VIRTUAL_ROUTER_ID 52

Priority 100

Advert_int 1

Authentication {

Auth_type PASS

Auth_pass 1111

}

Track_script {

Chk_http_port # (Invoke detection script)

}

virtual_ipaddress {

10.10.10.22/24 broadcast 10.10.10.255 Dev eth1 label Eth1:2

}

}

The following is a script for detecting nginx status

vim/usr/local/src/check_nginx_pid.sh

#!/bin/bash

A= ' ps-c nginx--no-header |wc-l '

If [$A-eq 0];then

/usr/local/nginx/sbin/nginx

If [' Ps-c nginx--no-header |wc-l '-eq 0];then

Killall keepalived

Fi

Fi

Script Plus executable permissions

chmod +x/usr/local/keepalived/sbin/check_nginx.sh

Network card status after service is turned on

[[Email protected] keepalived-1.2.15]# IP addr

1:lo: <LOOPBACK,UP,LOWER_UP> MTU 16436 qdisc noqueue State UNKNOWN

Link/loopback 00:00:00:00:00:00 BRD 00:00:00:00:00:00

inet 127.0.0.1/8 Scope host Lo

INET6:: 1/128 Scope Host

Valid_lft Forever Preferred_lft Forever

2:eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> MTU qdisc pfifo_fast State UNKNOWN Qlen 1000

Link/ether 00:50:56:22:04:B1 BRD FF:FF:FF:FF:FF:FF

inet 10.10.10.12/24 BRD 10.10.10.255 Scope Global eth1

inet 10.10.10.22/24 BRD 10.10.10.255 scope Global Secondary Eth1:2

Inet6 FE80::250:56FF:FE22:4B1/64 Scope link

Valid_lft Forever Preferred_lft Forever

3:pan0: <BROADCAST,MULTICAST> MTU Qdisc NoOp State down

Link/ether BE:88:BE:D6:81:A6 BRD FF:FF:FF:FF:FF:FF

[Email protected] keepalived-1.2.15]#

==================================== Test ============================

After testing that the Web Primary node service is down, the standby node service is functioning properly, and kill-9 Xxxxx,web still has access to

Analog keepalived node fails, Nginx server can automatically transfer

[[Email protected] sbin]# service keepalived stop

stopping keepalived: [OK]

Result Access VIP 21 is inaccessible, but 22 is still able to provide service as expected

Nginx+keepalived Dual Primary poll load balancing