NEC N8406-022 manual Address Resolution Protocol configuration, IGMP configuration, 600>

Address Resolution Protocol configuration

Address Resolution Protocol (ARP) is the TCP/IP protocol that resides within the Internet layer. ARP resolves a physical address from an IP address. ARP queries machines on the local network for their physical addresses. ARP also maintains IP to physical address pairs in its cache memory. In any IP communication, the ARP cache is consulted to see if the IP address of the computer or the router is present in the ARP cache. Then the corresponding physical address is used to send a packet.

The following table describes the ARP Configuration commands.

Table 93 ARP Configuration commands

Command	Description
ip arp rearp <2-120>	Defines re-ARP period in minutes. You can set this duration between 2 and
	120 minutes.
show ip arp	Displays the current ARP configurations.
	Command mode: All except User EXEC

IGMP configuration

IGMP Snooping allows the switch to forward multicast traffic only to those ports that request it. IGMP Snooping prevents multicast traffic from being flooded to all ports. The switch learns which server hosts are interested in receiving multicast traffic, and forwards it only to ports connected to those servers.

IGMP snooping configuration

The following table describes the IGMP Snooping Configuration commands.

Table 94 IGMP Snooping commands

Command	Description
ip igmp snoop timeout <1-255>	Sets the Maximum Response Time (MRT) for IGMP hosts.
	MRT is one of the parameters used to determine the age out
	period of the IGMP hosts. Increasing the timeout increases the
	age out period.
	The range is from 1 to 255 seconds. The default is 10 seconds.
	Command mode: Global configuration

ip igmp snoop mrouter-timeout <1-

600>

Configures the age-out period for the IGMP Mrouters in the Mrouter table. If the switch does not receive a General Query from the Mrouter for mrto seconds, the switch removes the multicast router from its Mrouter table.

The range is from 1 to 600 seconds. The default is 255 seconds.

Command mode: Global configuration

ip igmp snoop query-interval <1-600>	Sets the IGMP router query interval. The range is 1-600
	seconds. The default value is 125.
	Command mode: Global configuration
ip igmp snoop robust <2-10>	Configures the IGMP Robustness variable, which allows you to
	tune the switch for expected packet loss on the subnet. If the
	subnet is expected to be lossy (high rate of packet loss), then
	increase the value. The default value is 2.
	Command mode: Global configuration
[no] ip igmp snoop aggregate	Enables or disables IGMP Membership Report aggregation.
	Command mode: Global configuration
ip igmp snoop source-ip <IP address>	Configures the source IP address used as a proxy for IGMP
	Group Specific Queries.
	Command mode: Global configuration
ip igmp snoop vlan <1-4095>	Adds the VLAN to IGMP Snooping.
	Command mode: Global configuration
no ip igmp snoop vlan <1-4095>	Removes the VLAN from IGMP Snooping.
	Command mode: Global configuration
no ip igmp snoop vlan all	Removes all VLANs from IGMP Snooping.
	Command mode: Global configuration

Configuration Commands 84