Configuration Guide User guide

FastIron Configuration Guide 1591
53-1002494-02
Disabling CPU processing for select multicast groups
Brocade(config)#access-list 5 deny host 239.255.162.2
Brocade(config)#access-list 5 permit 239.255.0.0 0.0.255.255
Brocade(config)#router pim
Brocade(config-pim-router)#bsr-candidate loopback 1 32 100
Brocade(config-pim-router)#rp-candidate loopback 1 group-list 5
Syntax: [no] rp-candidate ethernet [<slotnum>/]<portnum> | loopback <num> | ve <num>
[group-list <access-list-num>]
The <slotnum> parameter is required on chassis devices.
The <portnum> | loopback <num> | ve <num> parameter specifies the interface. The Layer 3
switch will advertise the specified interface IP address as a candidate RP:
• Enter ethernet [<slotnum>/]<portnum> for a physical interface (port).
• Enter ve <num> for a virtual interface.
• Enter loopback <num> for a loopback interface.
The group-list <access-list-num> indicates that a standard ACL is used to filter for which multicast
group the advertisement will be made.
NOTE
Extended ACLs cannot be used for group-list.
Disabling CPU processing for select multicast groups
In IPv4 multicast, Brocade Layer 3 switches do not forward multicast packets with destination
addresses in the range between 224.0.0.0 and 224.0.0.255. These group addresses are reserved
for various routing protocols. By default, packets destined to these groups are processed by the
CPU. However, when a large number of packets for these groups are received by the Brocade
device all at once, CPU resources may be overloaded. To alleviate the load on the CPU, you could
disable CPU processing of packets for these groups. When applied, this feature protects the CPU
from traffic sent to IPV4 multicast addresses in the range 224.0.0.1 - 224.0.0.254, and instead
floods these packets in hardware within the incoming VLAN.
This feature can be applied on a VLAN or a VLAN-group. If applied on a VLAN, traffic received on a
port of the VLAN will be flooded to all other ports of the VLAN. If applied on a VLAN-group, traffic
will be flooded only at the individual VLAN level. Once this feature is applied on a VLAN or
VLAN-group, ports that are statically or dynamically added to the VLAN or VLAN-group will inherit
the configuration. Likewise, ports that are statically or dynamically removed from the VLAN or
VLAN-group will drop the configuration.
This feature can be enabled for packets destined to a multicast group or set of groups in the range
224.0.0.1 – 224.0.0.254, except for the reserved multicast addresses listed in the following table.
TABLE 269 Reserved multicast addresses
Multicast address Reserved for...
224.0.0.1 all nodes
224.0.0.2 PIM
224.0.0.3 DVMRP
224.0.0.4 DVMRP
224.0.0.5 OSPF