Brocade Multi-Service IronWare Switching Configuration Guide (Supporting R05.6.00) - Manual (Page 847)

Multi-Service IronWare Switching Configuration Guide 817
53-1003036-02
Configuring IP load sharing
19
• Packet type – The Brocade device can send Router Advertisement messages as IP broadcasts
or as IP multicasts addressed to IP multicast group 224.0.0.1. The packet type is IP broadcast.
• Maximum message interval and minimum message interval – When IRDP is enabled, the
Brocade device sends the Router Advertisement messages every 450 – 600 seconds by
default. The time within this interval that the Brocade device selects is random for each
message and is not affected by traffic loads or other network factors. The random interval
minimizes the probability that a host will receive Router Advertisement messages from other
routers at the same time. The interval on each IRDP-enabled Brocade device interface is
independent of the interval on other IRDP-enabled interfaces. The default maximum message
interval is 600 seconds. The default minimum message interval is 450 seconds.
• Hold time – Each Router Advertisement message contains a hold time value. This value
specifies the maximum amount of time the host should consider an advertisement to be valid
until a newer advertisement arrives. When a new advertisement arrives, the hold time is reset.
The hold time is always longer than the maximum advertisement interval. Therefore, if the hold
time for an advertisement expires, the host can reasonably conclude that the router interface
that sent the advertisement is no longer available. The default hold time is three times the
maximum message interval.
• Preference – If a host receives multiple Router Advertisement messages from different
routers, the host selects the router that sent the message with the highest preference as the
default gateway. The preference can be a number from 4294967296 to 4294967295. The
default is 0.
Enabling IRDP globally
To globally enable IRDP, enter the following command.
Brocade(config)# ip irdp
This command enables IRDP on the IP interfaces on all ports. Each port uses the default values for
the IRDP parameters. The parameters are not configurable when IRDP is globally enabled.
Enabling IRDP on an individual port
To enable IRDP on an individual interface and change IRDP parameters, enter commands such as
the following.
Brocade(config)# interface ethernet 1/3
Brocade(config-if-e10000-1/3)# ip irdp maxadvertinterval 400
This example shows how to enable IRDP on a specific port and change the maximum
advertisement interval for Router Advertisement messages to 400 seconds.
NOTE
To enable IRDP on individual ports, you must leave the feature globally disabled.
Syntax: [no] ip irdp [broadcast | multicast] [holdtime seconds] [maxadvertinterval seconds]
[minadvertinterval seconds] [preference number]
The broadcast | multicast parameter specifies the packet type the Brocade device uses to send
Router Advertisement.
• broadcast – The Brocade device sends Router Advertisement as IP broadcasts. This is the
default.