Brocade Communications Systems ICX 7250 series, Руководство по настройке

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External route summarization
An ASBR can be configured to advertise one external route as an aggregate for all redistributed routes that are covered by a specified
IPv6 address range.
When you configure an address range, the range takes effect immediately. All the imported routes are summarized according to the
configured address range. Imported routes that have already been advertised and that fall within the range are flushed out of the
autonomous system and a single route corresponding to the range is advertised.
If a route that falls within a configured address range is imported by the device, no action is taken if the device has already advertised the
aggregate route; otherwise, the device advertises the aggregate route. If an imported route that falls within a configured address range is
removed by the device, no action is taken if there are other imported routes that fall within the same address range; otherwise, the
aggregate route is flushed.
You can configure up to 32 address ranges.
The device sets the forwarding address of the aggregate route to 0 and sets the tag to 0. If you delete an address range, the advertised
aggregate route is flushed and all imported routes that fall within the range are advertised individually. If an external link-state database
(LSDB) overflow condition occurs, all aggregate routes and other external routes are flushed out of the autonomous system. When the
device exits the external LSDB overflow condition, all the imported routes are summarized according to the configured address ranges.
NOTE
If you use redistribution filters in addition to address ranges, the device applies the redistribution filters to routes first, and then
applies them to the address ranges.
NOTE
If you disable redistribution, all the aggregate routes are flushed, along with other imported
routes.
NOTE
Only imported, type 5 external LSA routes are affected. A single type 5 LSA is generated and flooded throughout the
autonomous system for multiple external routes.
OSPFv3 over VRF
OSPFv3 can run over multiple Virtual Routing and Forwarding (VRF) instances. OSPFv3 maintains multiple instances of the routing
protocol to exchange route information among various VRF instances. A multi-VRF-capable router maps an input interface to a unique
VRF, based on user configuration. These input interfaces can be physical or a switched virtual interface (SVI). By default, all input
interfaces are attached to the default VRF instance. All OSPFv3 commands are available over default and nondefault VRF instances.
Multi-VRF for OSPF (also known as VRF-Lite for OSPF) provides a reliable mechanism for trusted VPNs to be built over a shared
infrastructure. The ability to maintain multiple virtual routing or forwarding tables allows overlapping private IP addresses to be maintained
across VPNs. For details and a configuration example, refer to "Multi-VRF for OSPF" in the chapter "Multi-VRF."
OSPFv3 graceful restart helper
The OSPFv3 graceful restart (GR) helper provides a device with the capability to participate in a graceful restart in helper mode so that it
assists a neighboring routing device that is performing a graceful restart.
When OSPFv3 GR helper is enabled on a device, the device enters helper mode upon receipt of a grace-LSA where the neighbor state
is full. By default, the helper capability is enabled when you start OSPFv3, even if graceful restart is not globally enabled.
OSPFv3 graceful restart helper
Brocade FastIron Layer 3 Routing Configuration Guide
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