The time in milliseconds between repetitions of an initial membership report. Global setting on
interfaces without an overriding IGMP Setting.
Default: 1,000
4.7.5. Tunneling Multicast using GRE
It is possible to tunnel NetDefendOS multicast between two NetDefend Firewalls through a GRE
tunnel. The multicast server will be behind one firewall and the clients behind the other with a
GRE tunnel linking the two firewalls.
Setup Issues
There are certain issues that must be noted with tunneling multicast:
• Make sure that the multicast server is sending the stream with a higher TTL than 1 (VLC uses
TTL=1 by default).
• When using IGMP, make sure that the destination network is not set to all-nets. If it is, the
multiplex rule will not forward the stream to the correct interface.
• SAT Multiplex rules must be setup both on the firewall the server is behind and on the
firewall the clients are behind (in other words, the tunnel terminator).
• Incoming and outgoing IGMP rules for reporting and querying must be configured on both
sides of the tunnel if IGMP is used.
Tunneling Setup Summary
The following components are needed on both the client and server side:
• Configure a GRE Tunnel object with the remote network being the client network for the
server side and the server network on the client side.
• Configure routes that route multicast traffic bound for the network on the other side through
the GRE tunnel.
• Configure a MultiplexSAT IP rule and an Allow Multiplex IP rule on both sides.
• For the SAT Multiplex rules, enable the option: Multicast traffic must have been requested
using IGMP before it is forwarded.
• Configure IGMP rule objects for the multicast traffic.
An Example Configuration
An example multicast tunneling scenario is illustrated below.
Chapter 4: Routing
376
To Next Page
Loading...
