PIM routing

NOTES:

• You must have an advanced features license to use PIM routing.
• This feature is supported only on the SVI.

A FortiSwitch unit can operate as a Protocol Independent Multicast (PIM) version-4 router. FortiSwitchOS supports PIM source-specific multicast (SSM) and version 3 of Internet Group Management Protocol (IGMP).

You can configure a FortiSwitch unit to support PIM using the config router multicast CLI command. When PIM is enabled, the FortiSwitch unit allocates memory to manage mapping information. The FortiSwitch unit communicates with neighboring PIM routers to acquire mapping information and, if required, processes the multicast traffic associated with specific multicast groups.

NOTE:

• Access lists, prefix lists, and route maps are not supported.
• Bidirectional forwarding detection (BFD) is not supported.
• You cannot use PIM and the IGMP querier at the same time on the same switch virtual interface.
• PIM and IGMP snooping work independently.
• IPv6 is not supported.
• IGMP version-3 explicit membership tracking is not supported.
• SSM mapping is not supported.
• The multicast routing information base (MRIB) is not supported.
• The PIM management information base (MIB) is not supported.

This chapter covers the following topics:

• Terminology
• Configuring PIM
• Checking the PIM configuration

Terminology

PIM domain: A PIM domain is a logical area comprising a number of contiguous networks. The domain contains at least one Boot Strap Router (BSR) and a number of Rendezvous Points (RPs) and Designated Routers (DRs).

RP: An RP represents the root of a non-source-specific distribution tree to a multicast group.

Configuring PIM

To configure a PIM domain:

1. Determine the appropriate paths for multicast packets.
2. Make a note of the interfaces that will be PIM enabled. These interfaces can run a unicast routing protocol.
3. If you want multicast packets to be handled by specific (static) rendezvous points (RPs), record the IP addresses of the PIM-enabled interfaces on those RPs.
4. Enable PIM version 4 on all participating routers between the source and receivers. Use the config router multicast command to set global operating parameters.
5. Configure the PIM routers that have good connections throughout the PIM domain to be candidate boot strap routers (BSRs).
6. Configure one or more of the PIM routers to be candidate RPs.
7. If required, adjust the default settings of PIM-enabled interface(s).

To configure the source allowed for a multicast flow:

config router multicast-flow

edit <name>

set comments <string>

config flows

edit <muliticast-flow_entry_identifier>

set group-addr <224-239.xxx.xxx.xxx>

set source-addr <IP_address>

end

end

To configure a FortiSwitch unit to support PIM:

config router multicast

set multicast-routing {disable | enable}

config interface

edit {interface_name | internal | mgmt}

set pim-mode ssm-mode

set hello-interval <1-180>

set dr-priority <1-4294967295>

set multicast-flow <string>

config igmp

set query-interval <1-65535>

set query-max-response-time <1-25>

end

end

Checking the PIM configuration

Use the following commands to check your PIM configuration:

get router info multicast config

get router info multicast igmp {groups | sources | querier | interface | join | parameters}

get router info multicast pim {neighbour | interface}