CCIE2BE

Using same setup that we have been using in the last 3 posts, we will change the network type to point-to-multipoint Non-Broadcast we will also add a Ethernet link between R2 and R3 and enable OSPF on it Our final configuration should be something like this R1 interface Serial0/0   no ip address   encapsulation frame-relay   no frame-relay inverse-arp ! interface Serial0/0.123 multipoint   ip address 10.1.123.1 255.255.255.0   ip ospf network point-to-multipoint non-broadcast   ip ospf 1 area 0   frame-relay map ip 10.1.123.2 102   frame-relay map ip 10.1.123.3 103 !          router ospf 1   router-id 1.1.1.1   log-adjacency-changes   neighbor 10.1.123.2   neighbor 10.1.123.3 R2 interface Serial0/0   no ip address   encapsulation frame-relay   no frame-relay inverse-arp ! interface Serial0/0.123 multipoint   ip address 10.1.123.2 255.255.255.0   ...

using the same setup we used in the last 2 posts for Broadcast and Non-Broadcast Networks, but we will create multipoint interface on each router R1 interface Serial0/0   no ip address   encapsulation frame-relay   no frame-relay inverse-arp ! interface Serial0/0.123 multipoint   ip address 10.1.123.1 255.255.255.0   frame-relay map ip 10.1.123.2 102 broadcast   frame-relay map ip 10.1.123.3 103 broadcast R2 interface Serial0/0   no ip address   encapsulation frame-relay   no frame-relay inverse-arp ! interface Serial0/0.123 multipoint   ip address 10.1.123.2 255.255.255.0   frame-relay map ip 10.1.123.1 201 broadcast R3 interface Serial1/0   no ip address   encapsulation frame-relay   no frame-relay inverse-arp ! interface Serial0/0.123 multipoint   ip address 10.1.123.3 255.255.255.0   frame-relay map ip 10.1.123.1 301 broadcast we will enable OSPF under all sub interfaces interf s0/0.123 ...

We are building this lab on the previous lab OSPF – Non Broadcast Networks We will remove the neighbor statements from R1 OSPF process and also changing the OSPF network type under the serial interfaces to Broadcast R1 interface Serial0/0   ip address 10.1.123.1 255.255.255.0   encapsulation frame-relay   ip ospf network broadcast   ip ospf 1 area 0   frame-relay map ip 10.1.123.2 102   frame-relay map ip 10.1.123.3 103   no frame-relay inverse-arp R2 interface Serial0/0   ip address 10.1.123.2 255.255.255.0   encapsulation frame-relay   ip ospf network broadcast   ip ospf priority 0   ip ospf 1 area 0   frame-relay map ip 10.1.123.1 201   frame-relay map ip 10.1.123.3 201   no frame-relay inverse-arp R3 interface Serial1/0   ip address 10.1.123.3 255.255.255.0   encapsulation frame-relay   ip ospf network broadcast   ip ospf priority 0   ip ospf 1 area 0   frame-relay map ip...

In this post and the following posts we will try to explore OSPF network types, OSPF is a core technology in the CCIE lab so you need to be able to configure it without referring to the DoC-CD In Cisco world, OSPF comes in 6 Network types 1- Broadcast 2- Non-Broadcast 3- point-to-multipoint 4- point-to-multipoint Non-Broadcast (Cisco proprietary) 5- Loopback We will examine each of these network types over NBMA (Non Broadcast Multiple Access) Media like frame relay network since this is where the confusion coming from. We will start with the Non-Broadcast networks since it is the default OSPF network when you configure OSPF under frame relay physical interfaces Initial configurations R1 ! interface Serial0/0   ip address 10.1.123.1 255.255.255.0   encapsulation frame-relay   frame-relay map ip 10.1.123.2 102 broadcast   frame-relay map ip 10.1.123.3 103 broadcast   no frame-relay inverse-arp interf lo0 ip add 1.1.1.1 255.255.255.255 R2 ! ...

Topology consist of 3 OSPF areas Router R2 generates the following routes into Area 0 2.2.0.0/24 2.2.1.0/24 2.2.2.0/24 2.2.3.0/24 Router 5 generates the following routes into Area 135 5.5.0.0/24 5.5.1.0/24 5.5.2.0/24 5.5.3.0/24 Router 6 generates the following routes into Area 146 4.4.0.0/24 4.4.1.0/24 4.4.2.0/24 4.4.3.0/24 So let’s see how we can filter some Inter area routes Task 1 Filter these 2 prefixes 2.2.0.0/24 and 2.2.3.0/24 form being propagated outside area 0 and allow any other routes So do that we create a prefix list to deny these 2 routes and allow everything else ip prefix-list FROM_AREA0 seq 5 deny 2.2.0.0/24 ip prefix-list FROM_AREA0 seq 10 deny 2.2.3.0/24 ip prefix-list FROM_AREA0 seq 15 permit 0.0.0.0/0 le 32 then we apply a filter list under the ospf configuration   on R1, the filtering has to be done on the ABR routers We need to filter these routes out from Area 0 so the filter list will be applied outb...