Valid for 6.x and 7.x documentation, the description for both port_range and initial_hosts properties for TCPPING under "22.2.3. Configure TCPPING" could be improved.

As Paul Ferraro writes in an e-mail:

Additionally, the description of the initial_hosts property in the EAP
documentation is incomplete/misleading:
"A comma-separated list of the hosts which are considered well-known,
and will be available to look up the initial membership."

The value of the initial_hosts property includes a host and port
using the syntax: host[port]. The port_range applies to each address
specified in initial_hosts. The end result is that the port_range
effectively multiplies the set of potential initial members.
e.g.
if initial_hosts="host1[1000],host2[2000]" and port_range="2", TCPPING
will try to contact the following addresses when the channel is
connected:

host1:1000, host1:1001, host1:1002, host2:2000, host2:2001, host2:2002

The attributes are also well documented here: http://www.jgroups.org/manual/html/user-advanced.html, under "5.3.3.1. Using TCP and TCPPING"

Cc rhn-support-tmiyargi, pferraro@redhat.com