The generate action of mwalk runs the generate.pl perl script. Generate.pl produces two logs similar to the output from MHealth. This output can be parsed and used to build a representation of the multicast tree.
The user passes the hostname or IP address of a machine to use as the source of the generated tree and the name of a file with a list of receiver IPs. For each receiver, the script first pings the host to ensure that it is reachable. Then it attempts to perform an mtrace using the null group (0.0.0.0) producing the most likely reverse-path.
Each mtrace is timestamped to simulate the progression of a multicast session. The timestamp is incremented after a certain number of traces (block) have been attempted. The initial timestamp and the block size can be passed as parameters to the script.
To run the generate action, use the syntax listed below. If you want to generate logs for use with the other scripts, you must include the --log option. Otherwise, general statistics will be gathered and you have the option of building the trace list in memory (--build) that can then be queried interactively (--interactive). If a source is not specified, then the localhost will be used. The default receiver file is "receivers", the default timestamp is the current time, and the block size defaults to 10.
Generate.pl uses mtrace. The configure script does not check for its existence at the time of build/installation. The script assumes that it is in the user's search path.