...

To make this configuration work you need to ensure that Geronimo can resolve the virtual host name you are about to define. Depending on your network configuration you can add an entry to you DNS, an alias to the Geronimo server IP. Alternatively you can add an entry to the local host table, each operating system has it's own way to define a local host table. For example Windows will have %SystemRoot%\system32\drivers\etc\hosts

Define Virtual host

...
<module name="geronimo/tomcat/1.1/car">
<gbean gbeanInfo="org.apache.geronimo.tomcat.HostGBean" name="geronimo/tomcat/1.1/car?ServiceModule=geronimo/tomcat/1.1/car,j2eeType=Host,name=TomcatVirtualHost">
<attribute name="className">org.apache.catalina.core.StandardHost</attribute>
<attribute name="initParams">name=host1.com
       appBase=
       workDir=work</attribute>
</gbean>
...

Declare the virtual host in the deployment plan

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://geronimo.apache.org/xml/ns/j2ee/web-1.1">
	<environment>
		<moduleId>
			<groupId>sample.applications</groupId>
			<artifactId>HelloWorldApp</artifactId>
			<version>1.1</version>
		</moduleId>		
	</environment>
  	<context-root>/hello</context-root>
	<host>host1.com</host>
</web-app>

Deploy the application