Setting The Minimum Advertisement Interval; Setting The Advertisement Lifetime; Setting The Preference Levels For Router Ip Addresses - Alcatel-Lucent OmniSwitch 6850-48 Network Configuration Manual

Creating an RDP Interface

Setting the Minimum Advertisement Interval

To set the minimum amount of time, in seconds, that the RDP will allow between advertisements, use the
ip router-discovery interface min-advertisement-interval
command sets this value to 500 seconds for the Marketing IP router interface:
-> ip router-discovery interface Marketing min-advertisement-interval 500
Make sure that the value specified with this command is less than the current maximum advertisement
interval value. By default, this value is set to 0.75 * the default maximum interval value (450 seconds if
the maximum interval is set to its default value of 600 seconds).

Setting the Advertisement Lifetime

The advertisement lifetime value indicates how long, in seconds, the router IP address contained in an
advertisement packet is considered valid by a host. This value is entered into the lifetime field of an adver-
tisement packet so that it is available to hosts that receive these types of packets.
If a host does not receive another packet from the same router before the lifetime value expires, it assumes
the router is no longer available and will drop the router IP address from its table. As a result, it is impor-
tant that the lifetime value is always greater than the current maximum advertisement interval to ensure
router transmissions occur before the lifetime value expires.
To set the advertisement lifetime value for packets transmitted from a specific RDP interface, use the
ip router-discovery interface advertisement-lifetime
sets this value to 3000 seconds for RDP packets sent from the Marketing IP router interface:
-> ip router-discovery interface Marketing advertisement-lifetime 3000
By default, the lifetime value is set to 3 * the current maximum interval value (1800 seconds if the maxi-
mum interval is set to its default value of 600 seconds).

Setting the Preference Levels for Router IP Addresses

A preference level is assigned to each router IP address contained within an advertisement packet. Hosts
will select the IP address with this highest preference level to use as the default router gateway address. By
default, this value is set to zero.
To specify a preference level for IP addresses advertised from a specific RDP interface, use the
ip router-discovery interface preference-level
value to 10 for the IP address associated with the Marketing IP router interface:
-> ip router-discovery interface Marketing preference-level 10
Note that router IP address preference levels are only compared with the preference levels of other routers
that exist on the same subnet. Set low preference levels to discourage selection of a specific router.
page 29-10
command. For example, the following command
command. For example, the following command sets this
OmniSwitch AOS Release 6 Network Configuration Guide
command. For example, the following
Configuring RDP
September 2009