Multicast-Routing for Phone-System

Hello Everyone,

one of our customers has a phone system (Panasonic KX-NS700) that uses multicast to synchronize the Cell-Stations (KX-NS0154). The Cell-Stations (DECT) use PTP for synchronisation.There is one Master and several Slave-Stations. Although it is a coherent network, the Cell-Stations are located in different buildings and therefore also in different VLAN-Networks:

- 10.1.6.0/24 (Port1.16 / VLAN 16)
- 10.2.6.0/24 (Port1.26 / VLAN 26)
- 10.3.6.0/24 (Port1.36 / VLAN 36)
- 10.4.6.0/24 (Port1.46 / VLAN 46)


All VLAN-Networks are terminated on the same Firewall-System (Sophos XG Virtual / 19.5) and connected to the same network switches (Cisco SG350X). The Cell-Stations use the multicast group "239.0.0.1", although this could also be changed.

There are more than 20 Cell-Stations in total, but below I will give just one example for the sake of simplicity:

Master-Station: 10.1.6.200 (VLAN 16)
Slave-Station: 10.3.6.200 (VLAN 36)


I have done so until now:

- Configured IGMP-Snooping on Network Switches
- Disabled IGMP-Querier on Network Switches
- Configures PIM-SM on Firewall-System
- Configured Firewall-Rules (Temporary Any-Any between Subnets)

However, the Slave-Stations cannot synchronize with the Master-Station. I can't see anything unusual in the log (pimd.log).

I hope someone can help me and answer the following questions:

1: I disabled IGMP-Querier in the network switches. Is that correct?
2: Does PIM need an RP if there is only one router?
3: Are "Local service ACL exception rules" for Multicast needed?
4: Is PIM-SM or static multicast routing better?
5: What ist RP-Address "169.254.0.1"?


Thanks!

Regards, Sven