CASA CMTS-C2200 Broadcast

The issue is: Network Topology Is below

We are trying to send broadcast traffic from the CPE device hanging off the cable modems to the Head Linux PC via the CMTS-C2200. We are seeing that the broadcast traffic is being broadcast from Linux PC – B, but it is not being seen by Linux PC – A or C. Even though Linux PC – B and C are on the same network. This is also true if Linux PC – A sends a broadcast message, Linux PC – B and C will not receive it. We are seeing that the CMTS-C2200 is receiving lots of broadcast packets on the downstream, but none on the upstream.

Is there any way for us to set the CMTS-C2200 and/or our other networking equipment to allow broadcast traffic to flow to all devices on the same network and between networks?

For example:

Linux PC – B (10.20.31.0 /24) -> Broadcasts to Head Linux PC – A (10.20.30.0 /24)
Linux PC – C (10.20.31.0 /24) -> Broadcasts to Head Linux PC – A (10.20.30.0 /24)
Head Linux PC – A (10.20.30.0 /24) -> Broadcasts to Linux PC – B (10.20.31.0 /24)
Head Linux PC – A (10.20.30.0 /24) -> Broadcasts to Linux PC – C (10.20.31.0 /24)

Router – Is setup to send DHCP to Modems and CPE devices
CMTS-C2200 – Is on the 10.20.30.0 /24 network

My Docsis config is below.

Main
{
NetworkAccess 1;
MaxCPE 32;
DsServiceFlow
{
DsServiceFlowRef 2;
MaxRateSustained 0;
QosParamSetType 7;
}
UsServiceFlow
{
UsServiceFlowRef 1;
MaxConcatenatedBurst 4566;
MaxTrafficBurst 4566;
SchedulingType 2;
MaxRateSustained 0;
QosParamSetType 7;
}
/* CmMic 8b3702cea54aec8b2f77da4f264ce8f4; */
/* CmtsMic 3200625a1776dff37d477383b5f59293; */
/*EndOfDataMkr*/
}

Any advice or assistance would be greatly appreciated.