Goal for this Hackweek

mrouted is the de facto standard for DVMRP multicast routing on Linux and other Unices.

It has support for tunnels, but that does not include joining remote multicast groups. That becomes necessary when some switches with IGMP snooping enabled cut the transmission to the host running mrouted.

My goal is to help by fulfilling this need.

Resources

github issue

Progress

During hackweek:

• Monday: set up the test environment (6 VMs, 3 private networks, 1 GRE tunnel)
• Tuesday: played with multicast-oriented software:
  • mtools (msend/mreceive)
  • mcjoin
  • given up on Quicktime Darwin Streaming Server, too complicated to build on Linux (I might use it later, but on a Mac)
  • hit bug https://unix.stackexchange.com/questions/344325/cannot-disable-multicast-in-linux, worked around with iptables
  • mrouted
• Wednesday: got familiar with mrouted source code, designed first experimental code.
• Thursday: (day off)
• Friday: submitted final PR code

After hackweek:

• Tuesday 2023-02-08: acknowledged comments of first review
• Wednesday: applied suggestions
• Sunday: project owner merged PR