Proxying Local Multicast 224.0.0.1

[Kevan L. Brown]

I have a client application (Roku Tablo App) and a device (Tablo) that communicate with one another over multicast.  The client sends a UDP datagram on client:8882 to 224.0.0.1:8881 to discover the Tablo device.  The TTL on the packet is 1.

 

I have a Linux server with two interfaces; eth0 is on the subnet where the client is located and tap0 (OpenVPN client tap interface) which is on the subnet of the Tablo device.

 

Running mcproxy on the Linux server, the client doesn’t seem to be able to discover the Tablo on the remote subnet.  I’m assuming maybe 224.0.0.1 isn’t being proxied from the client subnet (eth0) to the Tablo device subnet (tap0).  Can you confirm if this is the case and if there is a workaround to make this function?

 

Thanks!

 

Kevan

[Sebastian Woelke]

Hey Kevan,

224.0.0.1 is the All host multicast group address, it is reserved for the multicast protocol internal use and with a TTL of 1 not routable.
(see https://www.iana.org/assignments/multicast-addresses/multicast-addresses.xhtml)
You should use another multicast address.

Regards,
Sebastian