DescriptionThis article describes how to configure the IGMP query message periodicity to keep or discard IGMP group information before the FortiGate as DR removes the member from the group and sends a prune message to the associated RP.SolutionOverview.
- When the client is ready to leave the multicast group, it sends an IGMP Leave Group message to the network and stops to be a member of the group.
- When FortiGate detects a leave request as DR, it sends an IGMP Query message to the receiver; if no response is received within the Max Response Time, FortiGate sends a second IGMP Query message and so on until it exceeds the Max Response Time or count set on FortiGate.
- If the FortiGate has already sent an IGMP query and the Max Response counter has been reached, the FortiGate DR removes the member from the group and sends a prune message to the associated RP.
CLI syntax.
# config router multicast
set multicast-routing enable
# config interface
edit "port4"
set pim-mode sparse-mode
set passive enable
# config join-group
edit “address”
set address “ipv4 address any” <----- Multicast group IP address.
next
# config igmp
set last-member-query-count “integer” <----- Number of group specific queries before removing group (2 - 7, default = 2). range [2-7].
set query-max-response-time “integer” <----- Maximum time to wait for a IGMP query response (1 - 25 sec, default = 10). range [1-25].
next
end
Related document.
https://docs.fortinet.com/document/fortigate/6.0.0/cli-reference/741750/router-multicast
