L the igmps flood traffic and igmps flood report

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The igmps-flood-traffic and igmps-flood-report settings must be disabled on the ISL and FortiLink
trunks; but the igmps-flood-traffic and igmps-flood-report settings must be enabled on ICL trunks.
These settings are enabled by default.
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IGMP proxy must be enabled.
Step 1: Ensure the MCLAG ICL is already configured between FortiSwitch 1 and FortiSwitch 2.
diagnose switch-controller switch-info mclag icl
Step 2: For each server, configure a trunk with MCLAG enabled. For server 1, select port10 on
FortiSwitch 1 and FortiSwitch 2. For server 2, select port15 on FortiSwitch 1 and FortiSwitch 2.
For details, refer to MCLAG trunks on page 74 .
Step 4: Verify the MCLAG configuration.
diagnose switch-controller switch-info mclag list
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MCLAG peer groups
Multi-tiered MCLAG with HA-mode FortiGate units
Use the following procedure to deploy tier-2 and tier-3 MCLAG peer groups from the FortiGate switch controller without
the need for direct console access to the FortiSwitch units.
NOTE:
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Fortinet recommends using at least two links for ICL redundancy.
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Before FortiOS 6.2.0, when using HA-mode FortiGate units to manage FortiSwitch units, the HA mode must be
active-passive. Starting in FortiOS 6.2.0, the FortiGate HA mode can be either active-passive or active-active.
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In this topology, you must use the auto-isl-port-group setting as described in the following configuration
example. This setting instructs the switches to group ports from MCLAG peers together into one MCLAG when the
inter-switch link (ISL) is formed.
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The auto-isl-port-group setting must be done directly on the FortiSwitch unit.
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On the global switch level, mclag-stp-aware must be enabled, and STP must be enabled on all ICL trunks. They
are both enabled by default.
NOTE: If you are going to use IGMP snooping with an MCLAG topology:
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On the global switch level, mclag-igmpsnooping-aware must be enabled. It is enabled by default.
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The igmps-flood-traffic and igmps-flood-report settings must be disabled on the ISL and FortiLink
trunks; but the igmps-flood-traffic and igmps-flood-report settings must be enabled on ICL trunks.
These settings are enabled by default.
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IGMP proxy must be enabled.
To create a three-tier FortiLink MCLAG topology, use FortiOS 6.2.3 GA or later and FortiSwitchOS 6.2.3 GA or later.
Tier-1 MCLAG
Wire the two core FortiSwitch units to the FortiGate devices. To configure the FortiSwitch units in the core, see
Transitioning from a FortiLink split interface to a FortiLink MCLAG on page 57 .
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MCLAG peer groups
Tier-2 and Tier-3 MCLAGs
1. Connect only the tier-2 MCLAG FortiSwitch units 3 and 4 to the core units 1 and 2 (leaving the other switches in
Closet 1 disconnected). Wait until they are discovered and authorized (authorization must be done manually if auto-
authorization is disabled).