Brocade Communications Systems Layer 3 Routing Configuration ICX 6650 - Manual (Page 256)

238 Brocade ICX 6650 Layer 3 Routing Configuration Guide
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OSPF V3 configuration
External route summarization
When the Brocade device is an OSPF Autonomous System Boundary Router (ASBR), you can
configure it 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 AS and a single route
corresponding to the range is advertised.
If a route that falls within a configured address range is imported by the Brocade 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 with in the same address
range; otherwise the aggregate route is flushed.
You can configure up to 32 address ranges. The Brocade device sets the forwarding address of the
aggregate route to zero and sets the tag to zero.
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 overflow (LSDB) condition occurs, all aggregate routes are flushed
out of the AS, along with other external routes. When the Brocade 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 Brocade device applies the
redistribution filters to routes first, then applies them to the address ranges.
NOTE
If you disable redistribution, all the aggregate routes are flushed, along with other imported routes.
NOTE
This option affects only imported, type 5 external routes. A single type 5 LSA is generated and
flooded throughout the AS for multiple external routes.
Configuring external route summarization
To configure the summary address 2001:db8::/24 for routes redistributed into OSPF V3, enter the
following command.
Brocade(config-ospf6-router)#summary-address 2001:db8::/24
In this example, the summary prefix 2001:db8::/24 includes addresses 2001:db8::/1 through
2001:db8::/24. Only the address FEC0::/24 is advertised in an external link-state advertisement.
Syntax: summary-address ipv6-prefix/prefix-length
You must specify the ipv6-prefix parameter in hexadecimal using 16-bit values between colons as
documented in RFC 2373.
You must specify the prefix-length parameter as a decimal value. A slash mark (/) must follow the
ipv6-prefix parameter and precede the prefix-length parameter.