nginx + keepalived hot standby

For the medium and small enterprises, if not the money to buy expensive four / seven load balancing switches, then Nginx is a good seven load balancing options, and can achieve double the load balancer Nginx via Nginx + Keepalived mutual support, any one machine fails, the other can take over the virtual IP in the past. The following is the third update, the following detailed description of its installation steps below:

First, install nginx, has been installed on a step, see the article

Second, install keepalived

keepalived Download: http: //www.keepalived.org/software/
wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz
tar zxvf keepalived-1.2.2.tar.gz
cd keepalived-12.2. / configure –prefix = / usr / local / keepalived
make
make install
cp / usr / local / keepalived / sbin / keepalived / usr / sbin /
cp / usr / local / keepalived / etc / sysconfig / keepalived / etc / sysconfig /
cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
mkdir / etc / keepalived
cd / etc / keepalived /

The main configuration file

vim keepalived.conf

 

1. global_defs {        ####全局定义
2.    notification_email {        #####指定keepalived在发生事件时(比如切换),需要发送的email对象,可以多个,每行一个
3.     123@qq.com
4.    }
5.    notification_email_from 123@qq.com
6.    smtp_server 127.0.0.1          #####指定发送email的smtp服务器
7.    smtp_connect_timeout 30
8.    router_id LVS_DEVEL          #######运行keepalived的机器的一个标识
9. }
10. vrrp_sync_group VG1 {
11.   group {
12.     VI_1
13.     VI_2
14.    }
15. }
16. vrrp_script chk_nginx {
17.         script    “/etc/chk_nginx.sh”     ###监控脚本
18.         interval 2      ###监控时间
19.         #weight -2
21. }
22. vrrp_instance VI_1 {
23.     state MASTER
24.     interface eth0
25. #    track_interface {
26. #       eth0
27. #       eth1
28. #   }
29.     virtual_router_id 51      #VRID标记 master和backup必须一致
30.     mcast_src_ip 192.168.2.113
31.     #发送多播包的地址,如果不设置默认使用绑定的网卡的primary ip
32.     priority 150
33.     advert_int 1
34.     authentication {
35.         auth_type PASS
36.         auth_pass 1111
37.     }
38.    track_script {
39.         chk_nginx         ### 就是上面vrrp_script后面的实例名称   执行监控的服务
40.     }
41.     virtual_ipaddress {
42.        192.168.2.116
43.         }
44. }
46. vrrp_instance VI_2 {
47.     state BACKUP
48.     interface eth0
49.     tual_router_id 52
50.     mcast_src_ip 192.168.100.113
51.     priority 149
52.     advert_int 1
53.     authentication {
54.         auth_type PASS
55.         auth_pass 1111
56.     }
57. #    track_interface {
58. #       eth0
59. #       eth1
60. #    }
61.     virtual_ipaddress {
62.        192.168.100.117
63.         }
64. }

 

另一主的配置文件

 

 

1. global_defs { ####全局定义
2. notification_email { #####Keepalived specified when an event occurs (such as switching), email subject you want to send, can more than one, one per line
3. 123.com
4. }
5. notification_email_from 123@qq.com
6. smtp_server 127.0.0.1 #####指定发送email的smtp服务器
7. smtp_connect_timeout 30
8. router_id LVS_DEVEL #######运行keepalived的机器的一个标识
9. }
10. vrrp_sync_group VG1 {
11. group {
12. VI_1
13. VI_2
14. }
15. }
16. vrrp_script chk_nginx {
17. script “/etc/chk_nginx.sh” ###监控脚本
18. interval 2 ###监控时间
19. #weight -2
21. }
22. vrrp_instance VI_1 {
23. state BACKUP
24. interface eth0
25. # track_interface {
26. # eth0
27. # eth1
28. # }
29. virtual_router_id 51 #VRID标记 master和backup必须一致
30. mcast_src_ip 192.168.2.112
31. #发送多播包的地址,如果不设置默认使用绑定的网卡的primary ip
32. priority 149
33. advert_int 1
34. authentication {
35. auth_type PASS
36. auth_pass 1111
37. }
39. virtual_ipaddress {
40. 192.168.2.116
41. }
42. }
44. vrrp_instance VI_2 {
45. state MASTER
46. interface eth0
47. tual_router_id 52
48. mcast_src_ip 192.168.100.112
49. priority 150
50. advert_int 1
51. authentication {
52. auth_type PASS
53. auth_pass 1111
54. }
55. track_script {
56. chk_nginx ### The above is an example of the name behind vrrp_script execution monitoring service
57. }
58. # track_interface {
59. # eth0
60. # eth1
61. }
62. virtual_ipaddress {
63. 192.168.100.117
64. }
65. }

### At the time of writing the above configuration must pay attention to a space where we must add (a lot of small details must pay attention)

Here is their definition monitor nginx script chk_nginx.sh

 

 

1. vim  chk_nginx.sh
2. #!/bin/bash
3. url=“http://192.168.100.1/index.html”
4. status=$(/usr/bin/curl -s –head “$url”|awk ‘/HTTP/ {print $2}’)
5. if[ “$status” != “200” ]; then
6. /etc/init.d/keepalived stop
7. fi