Brocade FastIron Ethernet Switch IP Multicast Configuration Guide - Manual (Page 20)

• Configuring the IGMP mode for a VLAN (active or passive)
• Disabling IGMP snooping on a VLAN
• Configuring the IGMP version for a VLAN
• Configuring static router ports
• Turning off static group proxy
• Enabling IGMP V3 membership tracking and fast leave for the VLAN
• Enabling fast leave for IGMP
• Enabling fast convergence
Perform the following port-specific IGMP snooping task:
• Configuring the IGMP version for individual ports in a VLAN
IGMP snooping mcache entries and group addresses
An IGMP snooping group address entry is created when an IGMP join message is received for a
group. An IGMP snooping mcache entry is created when data traffic is received for that group. Each
mcache entry represents one data stream, and multiple mcache entries (up to 32) can share the same
hardware (MAC) address entry. The egress port list for the mcache entry is obtained from the IGMP
group address entry. If there is no existing IGMP group address entry when an mcache entry is
created, data traffic for that multicast group is dropped in hardware. If there is an existing IGMP group
address entry when an mcache is created, data traffic for that multicast group is switched in hardware.
The following describes the IGMP snooping software resource limits for Brocade devices:
• FCX, FSX, ICX 6610, and ICX 6450 devices support up to a maximum of 8192 IGMP snooping
multicast cache (mcache) entries and a maximum of 8192 IGMP group addresses.
• ICX 6430 devices support up to 2048 IGMP snooping multicast cache (mcache) entries and a
maximum of 4096 IGMP group addresses.
• ICX 6650 devices support 8192 IGMP snooping mcache entries and 8192 IGMP groups
addresses.
• ICX 7750 switches support 8192 IGMP snooping mcache entries and 8192 IGMP group
addresses.
• ICX 7750 routers support 6K IGMP snooping mcache entries and 8192 IGMP group addresses.
The default for IGMP snooping mcache entries is 512, with the exception of ICX 6430 devices where
the default is 256.
Changing the maximum number of supported IGMP snooping mcache
entries
You can configure the system-max igmp-snoop-mcache command to change the maximum number
of IGMP snooping cache entries supported on a device.
Device(config)#system-max igmp-snoop-mcache 2000
Syntax: [no] system-max igmp-snoop-mcache num
The num variable is a value from 256 through 8192. The default is 512.
IGMP snooping mcache entries and group addresses
18 FastIron Ethernet Switch IP Multicast Configuration Guide
53-1003085-02