Brocade Communications Systems ICX 7250 series, Configuration Manual

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NOTE
For an external route that is redistributed into OSPFv3 through a route map, the metric value of the route remains the same
unless the metric is set by the
set metric command inside the route map or the default-metric command. For a route
redistributed without using a route map, the metric is set by the metric parameter if set or the default-metric command if the
metric parameter is not set.
Default route origination
When the device is an OSPFv3 Autonomous System Boundary Router (ASBR), you can configure it to automatically generate a default
external route into an OSPFv3 routing domain.
By default, a device does not advertise the default route into the OSPFv3 domain. If you want the device to advertise the OSPFv3
default route, you must explicitly enable default route origination. When you enable OSPFv3 default route origination, the device
advertises a type 5 default route that is flooded throughout the autonomous system, with the exception of stub areas.
The device advertises the default route into OSPFv3 even if OSPFv3 route redistribution is not enabled, and even if the default route is
learned through an IBGP neighbor. The device does not, however, originate the default route if the active default route is learned from an
OSPFv3 router in the same domain.
NOTE
The device does not advertise the OSPFv3 default route, regardless of other configuration parameters, unless you explicitly
enable default route origination.
If default route origination is enabled and you disable it, the default route originated by the device is flushed. Default routes generated by
other OSPFv3 devices are not affected. If you re-enable the default route origination, the change takes effect immediately and you do
not need to reload the software.
Filtering OSPFv3 routes
You can filter the routes to be placed in the OSPFv3 route table by configuring distribution lists. OSPFv3 distribution lists can be applied
globally or to an interface.
The functionality of OSPFv3 distribution lists is similar to that of OSPFv2 distribution lists. However, unlike OSPFv2 distribution lists,
which filter routes based on criteria specified in an Access Control List (ACL), OSPFv3 distribution lists can filter routes using information
specified in an IPv6 prefix list or a route map.
SPF timers
The device uses an SPF delay timer and an SPF hold-time timer to calculate the shortest path for OSPFv3 routes. The values for both
timers can be changed.
The device uses the following timers when calculating the shortest path for OSPFv3 routes:
• SPF delay: When the device receives a topology change, it waits before starting a Shortest Path First (SPF) calculation. By
default, the device waits 5 seconds. You can configure the SPF delay to a value from 0 through 65535 seconds. If you set the
SPF delay to 0 seconds, the device immediately begins the SPF calculation after receiving a topology change.
• SPF hold time: The device waits a specific amount of time between consecutive SPF calculations. By default, it waits 10
seconds. You can configure the SPF hold time to a value from 0 through 65535 seconds. If you set the SPF hold time to 0
seconds, the device does not wait between consecutive SPF calculations.
SPF timers
Brocade FastIron Layer 3 Routing Configuration Guide
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