After your external web server has been configured, the JRun connector will establish a connection with the specified JRun server every time the web server is started. This TechNote describes what happens when the web server starts up and some changes that occurred after JRun 4 Updater 2.
Upon startup, the web server calls the initialization method of the JRun connector. At this time the JRun Connector attempts to build a connection to the JRun Proxy Service using the IP address and port specified in the bootstrap setting or the jrunserver.store file. Depending on your web server, the bootstrap is stored in different places:
- Apache: in the httpd.conf file
- IIS: in the jrun.ini file
- SunOne, iPlanet, Netscape: in the magnus.conf file
If the bootstrap setting does not work, it then looks for a jrunserver.store file to see if this server is in a cluster. If it is, it attempts to create a proxy connection for each IP\port entry until it is successful.
When the connector finds it's bootstrap server, as it normally would, the JRun server returns the IP address of the server. It is this IP address that will be used to create the connection between the connector and the JRun server. If your server has more then one IP address, multiple NIC cards, you may see the JRun connector use a different IP than what you specified in the bootstrap setting. This may be problematic if using a firewall. Turning on verbose logging can easily identify what IP is being used by the connector. The verbose setting is together with the bootstrap setting, respective to the above web servers.
In a clustered environment, once the connector connects to a server, the connector updates the jrunserver.store file with the latest live server list. JRun manages the jrunserver.store file and you have no need to make any changes to the file.
The JRun connector would not use the returned IP from the JRun Server. It would simply use the values from the bootstrap setting or jrunserver.store file. This was problematic with clustering and was changed with Updater 3 to use the IP returned from the JRun Server.