Installation and testing of Nginx load Balancer

installation and testing of Nginx load Balancer 1. Configure 3 Machines

A server ip:192.168.157.128 (master)

b Server ip:192.168.157.136

C Server ip:192.168.157.137

Vim/etc/hosts

192.168.157.128 HADOOP1
192.168.157.136 HADOOP2
192.168.157.137 HADOOP3

2. nginx.conf setting

A server nginx.conf settings
Open nginx.conf, and the file location is in the Conf directory of the Nginx installation directory.

Add the following code to the HTTP segment

Upstream A.com {
Server 192.168.157.136:80;
Server 192.168.157.137:80;
}

server{
Listen 80;
server_name HADOOP1;
Location/{
Proxy_pass Http://hadoop1;
Proxy_set_header Host $host;
Proxy_set_header X-real-ip $remote _addr;
Proxy_set_header x-forwarded-for $proxy _add_x_forwarded_for;
}
}

Save Restart Nginx-s Reload

Configure the B, C server nginx.conf settings separately
Open Nginx.confi and add the following code to the HTTP segment

server{
Listen 80;
server_name HADOOP1;
Index index.html;
}

Restart the B, C server nginx-s reload respectively

Differentiated interface:
192.168.157.128 vim/usr/local/nginx/html/index.html content is HADOOP1
192.168.157.136 vim/usr/local/nginx/html/index.html content is HADOOP2
192.168.157.137 vim/usr/local/nginx/html/index.html content is HADOOP3
3. Restart A, B, and C servers respectively

Nginx-s Reload

Access the HTTP://HADOOP1:80 refresh interface to see the interface content as HADOOP2 or HADOOP3
Conclusion:
Open the browser to access the HTTP://HADOOP1:80 results, The refresh discovers that all requests are allocated to B server (192.168.157.136) and C server (192.168.157.137), respectively, by the primary server (192.168.157.128), and the load balancing effect is achieved.


4. Simulate a server outage

What if one of the servers goes down.
When a server goes down, does it affect access?

Let's take a look at the example above, assuming that the C server 192.168.157.137 the machine is down (because it can't emulate the outage, so I shut down the C server) and then come back to see it.

Access Result: HADOOP2

We found that although the C server (192.168.157.137) was down, it did not affect website access. This way, there is no fear of dragging the entire site in a load-balancing mode because of a machine outage.