In this scenario there are two fabric environments installed on the same host. The child containers created in this environment can attempt to use ports that are already in use by the other fabric environment.

Take the following example:

In a 6.1 environment the root container will default to bind to port 8101 for SSH. In another environment 6.2 is setup and the default ports are configured to not clash with the exiting 6.1 environment, however when a child container is created in the 6.2 environment it tries to bind to port 8101 for SSH. Additionally is tries to bind to the default RMI ports which are also used by the original 6.1 root container:

JBossFuse:karaf@root> fabric:container-create-child root rc1
Creating new instance on SSH port 8101 and RMI ports 1099/44444 at: /Users/jsherman/Development/tools/jboss-fuse/jboss-fuse-6.2.0.redhat-133/instances/rc1
The following containers have been created successfully:
	Container: rc1.
JBossFuse:karaf@root>