配置实例:如何过滤ospf中的lsa3

admin

ospf中的新特性，对ios的版本要求较高：
　　
　　The OSPF ABR Type 3 LSA Filtering feature is supported for the following platforms in Cisco IOS
　　Release 12.2(4)T:
　　· Cisco 1400 series
　　· Cisco 1600 series
　　· Cisco 1600R series
　　· Cisco 1720
　　· Cisco 1721 (Supported in Cisco IOS Release 12.2(8)T and above.)
　　· Cisco 1750
　　· Cisco 1751
　　· Cisco 2500 series
　　· Cisco 2600 series
　　· Cisco 3620
　　· Cisco 3631 (Supported in Cisco IOS Release 12.2(8)T and above.)
　　· Cisco 3640
　　· Cisco 3745 (Supported in Cisco IOS Release 12.2(8)T and above.)
　　· Cisco 3660
　　· Cisco MC3810
　　· Cisco 7100 series
　　· Cisco 7200 series
　　· Cisco 7500 series (Supported in Cisco IOS Release 12.2(4)T3 and above.)
　　· Cisco uBR7200 series
　　· Universal Router Module (Supported in Cisco IOS Release 12.2(8)T.)
　　
　　以下配置在abr上完成
　　
　　配置步骤：
　　
　　1，过滤进入某AREA的LSA3
　　
　　Command Purpose
　　Router(config)# router ospf process-id
　　Configures the router to run an OSPF process.
　　
　　
　　Router(config-router)# area area-id filter-list prefixprefix-list-name in
　　Configures the router to filter interarea routes into the specified area.
　　
　　
　　Router(config-router)# ip prefix-list list-name [seq seq-value] deny | permit network/len [ge ge-value] [le le-value]
　　Creates a prefix list with the name specified for thelist-name argument.
　　
　　2，过滤从某AREA出去的LSA3
　　
　　Router(config)# router ospf process-id
　　Configures the router to run an OSPF process.
　　
　　Router(config-router)# area area-id filter-list prefix prefix-list-name out
　　Configures the router to filter interarea routes out of the specified area.
　　
　　
　　Router(config-router)# ip prefix-list list-name [seq seq-value] deny | permit network/len [ge ge-value] [lele-value]
　　Creates a prefix list with the name specified for the list-name argument.
　　
　　3检查配置
　　
　　router# show ip ospf 1
　　
　　
　　Routing Process "ospf 1" with ID 172.16.0.1
　　Supports only single TOS(TOS0) routes
　　Supports opaque LSA
　　It is an area border router
　　SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
　　Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
　　Number of external LSA 0. Checksum Sum 0x0
　　Number of opaque AS LSA 0. Checksum Sum 0x0
　　Number of DCbitless external and opaque AS LSA 0
　　Number of DoNotAge external and opaque AS LSA 0
　　Number of areas in this router is 2. 2 normal 0 stub 0 nssa
　　External flood list length 0
　　Area BACKBONE(0)
　　Number of interfaces in this area is 2
　　Area has no authentication
　　SPF algorithm executed 6 times
　　Area ranges are
　　10.0.0.0/8 Passive Advertise
　　Area-filter AREA_0_IN in
　　Area-filter AREA_0_OUT out
　　Number of LSA 5. Checksum Sum 0x29450
　　
　　4，配置举例
　　
　　Router(config)# router ospf 1
　　log-adjacency-changes
　　area 1 filter-list prefix AREA_1_OUT out
　　area 3 filter-list prefix AREA_3_IN in
　　network 10.0.0.0 0.255.255.255 area 3
　　network 172.16.1.0 0.0.0.255 area 0
　　network 192.168.0.0 0.255.255.255 area 1
　　!
　　ip prefix-list AREA_1_OUT seq 10 permit 10.25.0.0/8 ge 16
　　ip prefix-list AREA_1_OUT seq 20 permit 172.20.20.0/24
　　!
　　ip prefix-list AREA_3_IN seq 10 permit 172.31.0.0/16