Nonstop Forwarding For Ospf Version 2 - Cisco NCS 5500 Series Configuration Manuals

Implementing OSPF
RP/0/RP0/CPU0:router(config-ospf)# summary-prefix 10.1.0.0 255.255.0.0
or
RP/0/RP0/CPU0:router(config-router)# summary-prefix 2010:11:22::/32
(Optional) Creates aggregate addresses for OSPF.
or
(Optional) Creates aggregate addresses for OSPFv3.
• This command provides external route summarization of the non-OSPF routes.
• External ranges that are being summarized should be contiguous. Summarization of overlapping ranges from two
different routers could cause packets to be sent to the wrong destination.
• This command is optional. If you do not specify it, each route is included in the link-state database and advertised
in LSAs.
• In the OSPFv2 example, the summary address 10.1.0.0 includes address 10.1.1.0, 10.1.2.0, 10.1.3.0, and so on. Only
the address 10.1.0.0 is advertised in an external LSA.
• In the OSPFv3 example, the summary address 2010:11:22::/32 has addresses such as 2010:11:22:0:1000::1,
2010:11:22:0:2000:679:1, and so on. Only the address 2010:11:22::/32 is advertised in the external LSA.
Step 6
commit
Example
The following example uses prefix lists to limit the routes redistributed from other protocols.
Only routes with 9898:1000 in the upper 32 bits and with prefix lengths from 32 to 64 are redistributed
from BGP 42. Only routes not matching this pattern are redistributed from BGP 1956.
ipv6 prefix-list list1
seq 10 permit 9898:1000::/32 ge 32 le 64
ipv6 prefix-list list2
seq 10 deny 9898:1000::/32 ge 32 le 64
seq 20 permit ::/0 le 128
router ospfv3 1
router-id 10.0.0.217
redistribute bgp 42
redistribute bgp 1956
distribute-list prefix-list list1 out bgp 42
distribute-list prefix-list list2 out bgp 1956
area 1
interface TenGigE 0/2/0/0

Nonstop Forwarding for OSPF Version 2

NSF for OSPF Version 2 allows for the forwarding of data packets to continue along known routes while the
routing protocol information is being restored following a failover. With NSF, peer networking devices do
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
Nonstop Forwarding for OSPF Version 2
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