Configuring a load balancer with a firewall, web servers, and multiple AR System servers
In this example, client requests pass through a firewall and into the load balancer. The load balancer directs the web requests to three web servers. The web servers access the BMC Remedy AR System servers to fulfill BMC Remedy AR System requests. The three servers share a single database, as shown in the following figure.
Load-balancer configuration with a firewall, web servers, and AR System servers
(Click the image to expand it.)
Using the hosts file, the IP address of the AR System server needs to be resolved manually on each web server. This is necessary because all web servers reference the same AR System server name; however, each web server is linked to a different AR System server, and each AR System server has a different IP address. If the server name was resolved using a DNS server, this server name would resolve to the same IP address and all the web servers would communicate with the same AR System server. Therefore, each web server uses the hosts file, and manually resolves the AR System server name to the appropriate server.
On Windows platforms, the hosts file is located in the %WINDIR%\system32\ drivers\etc directory. On UNIX, the hosts file is located in the /etc directory.
- The hosts file on Web 1 should include the following line: myarserver 22.214.171.124
- The hosts file for Web 2 should include the following line: myarserver 126.96.36.199
- The hosts file for Web 3 should include the following line: myarserver 188.8.131.52
In the preceding sample hosts files, myarserver is the AR System server name that all the web servers reference.