i always seem to forget type 4, summary asbr... i think humans have a natural aversion to this type...
1 is easy router type
2 is easy network type
3 is easy summary net
the view of the network from r1 can be counted on as a baseline...
r1# sh ip route
Gateway of last resort is not set
1.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 1.1.1.0/24 is directly connected, Loopback1
L 1.1.1.1/32 is directly connected, Loopback1
10.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
C 10.1.1.0/24 is directly connected, FastEthernet0/0
L 10.1.1.1/32 is directly connected, FastEthernet0/0
C 10.1.2.0/24 is directly connected, FastEthernet1/1
L 10.1.2.1/32 is directly connected, FastEthernet1/1
O IA 192.168.1.0/24 [110/782] via 10.1.1.2, 00:09:00, FastEthernet0/0
O IA 192.168.2.0/24 [110/782] via 10.1.2.2, 00:09:00, FastEthernet1/1
this gives us hope... area 0 is bounded by area 1, and is duly noted in the route table...
we can get to the outermost reaches of area 1...
r1#ping 192.168.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/9/20 ms
the ospf database also tells us this...
r2 and r3 are transit areas creating the summary net advertisements, as well as performing dr duty...
note that r4 and r5, neither transit nor dr, do not exhibit type 2's...
so we turn on basic redistribution on r4 and r5 from eigrp 1 and watch the fireworks...
note that the advertising routers are r2 and r3 from r1's perspective...
r2 claims responsibility for propagating the type 4's...
and r4 (one of the asbr's) is in complete agreement...
look especially hard at the summary asb (type 4) advertising router... although the type 4 couldn't originate without the asbr, it is the abr that propagates the type 4, both ways...
dr's propagate advertisements... i read that somewhere once...
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