Macromedia colfusion mx 7 Manual

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Chapter 7:  Using Multiple Server Instances

Enabling application isolation

You can create separate server instances, each with its own ColdFusion applications; each 
application then has its own ColdFusion and J2EE server resources. In this configuration, you 
typically have a single external web server with multiple server instances on one computer, and 
separate virtual hosts (or sites) for each server instance.

Note: Although this section describes using ColdFusion MX, other J2EE application servers provide 
equivalent capabilities, and most of the concepts apply when deploying the ColdFusion MX J2EE 
configuration on those J2EE servers.

Running independent applications this way has several advantages, including the following:

•

Errors at the levels of the ColdFusion application or the JRun server do not affect any other 
ColdFusion applications.

•

You can support multihomed servers, where a single web server supports multiple IP addresses 
or domain names, such as www.mycompany.com and services.anothercompany.com, each 
running from a separate web root. For more information, see 

•

Individual applications can use different JVM configurations, or even different JVM 
implementations. This feature is particularly useful if one application requires a particularly 
large Java heap. To specify customized JVM options, start the JRun server instance from the 
command line using the 

-config

 option of the 

jrun

 command, which specifies a customized 

jvm.config file. This is explained in the “Starting and stopping JRun servers” section in 
Installing and Using ColdFusion MX.

Note: These instructions describe creating multiple server instances on a single computer. To create 
multiple server instances on separate computers, each computer requires a separate license of 
ColdFusion MX Enterprise Edition.

To achieve complete application isolation, you use web-server-specific functionality to create a 
separate website for each application. Web servers have different terminology for this concept. For 
example, in IIS, you define separate websites (available in Windows server editions only) and in 
Apache, you create multiple virtual hosts.

These instructions apply when running ColdFusion MX in the multiserver configuration. The 
principles apply when running ColdFusion MX on other J2EE application servers. However, not 
all J2EE application servers integrate with external web servers. For more information, see 

These instructions assume that you deploy each application at a named context root, which 
enables users to access CFM pages by specifying http://hostname/context-root/pagename.cfm. If 
other web applications are running in the server instance, each web application must use a 
different context root.

For example, with a context root of cfmx, users access CFM pages by specifying 
http://hostname/

cfmx/pagename.cfm. For more information on using a context root, see Installing 

and Using ColdFusion MX.

Note: Although cfmx is the context root, it does not relate to your web application directory structure.