Example 3: Summarizing Routes - Lenovo Flex System Fabric CN4093 Application Manual

Other Virtual Link Options

Example 3: Summarizing Routes

1. Configure IP interfaces for each network which will be attached to OSPF areas.
2. Enable OSPF.
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CN4093 Application Guide for N/OS 8.2
You can use redundant paths by configuring multiple virtual links.

 Only the endpoints of the virtual link are configured. The virtual link path may
traverse multiple routers in an area as long as there is a routable path between
the endpoints.
By default, ABRs advertise all the network addresses from one area into another
area. Route summarization can be used for consolidating advertised addresses and
reducing the perceived complexity of the network.
If the network IP addresses in an area are assigned to a contiguous subnet range,
you can configure the ABR to advertise a single summary route that includes all
the individual IP addresses within the area.
The following example shows one summary route from area 1 (stub area)
injected into area 0 (the backbone). The summary route consists of all IP addresses
from 36.128.192.0 through 36.128.254.255 except for the routes in the range
36.128.200.0 through 36.128.200.255.
Note: OSPFv2 supports IPv4 only. IPv6 is supported in OSPFv3 (see
Implementation in Lenovo N/OS" on page
Figure 52. Summarizing Routes
Backbone
Area 0
(0.0.0.0)
IF 1
10.10.7.1
Summary Route
10.10.7.0/24
Network
Note: You can specify a range of addresses to prevent advertising by using the
hide option. In this example, routes in the range 36.128.200.0 through
36.128.200.255 are kept private.
Follow this procedure to configure OSPF support as shown in Figure
CN4093(config)# interface ip 1
CN4093(config­ip­if)# ip address 10.10.7.1 255.255.255.0 enable
CN4093(config­ip­if)# exit
CN4093(config)# interface ip 2
CN4093(config­ip­if)# ip address 36.128.192.1 255.255.255.0 enable
CN4093(config­ip­if)# exit
CN4093(config)# router ospf
CN4093(config­router­ospf)# enable
444).
Stub Area
Area 1
(0.0.0.1)
IF 2
36.128.192.1
36.128.192.x to
ABR
36.128.254.x
36.128.192.0/18
Network
"OSPFv3
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