03-17-2010, 06:24 PM
Ok I am sorry but this makes no sense to me. I actually would have chosen the two ip prefix-lists just out of process of elimination
172.16.x.x network = RIPv2 routes
10.x.x.x network = OSPF routes
first off the access-list 15 statement is a denial and it is attached to a route-map that is also a denial statement. Followed by permit any statements. Which means that you are denying the access-list from being denied but permitting all other traffic. You can do that for sure but it won't accomplish any filtering. So because of that I crossed it off the list.
access-list 15 deny 10.1.1.0 0.0.0.63
access-list 15 permit any
route-map redis-rip deny 10
match ip address 15
route-map redis-rip permit 20
router ospf 100
redistribute rip route-map redis-rip subnets
Second of all access-list 40 statement is a denial of OSPF routes and that denial statement is incorporated into the RIP process denying these routes from being advertised out by rip. So uh... that defeats the purpose. Its like saying RIP, you see these OSPF routes that you are trying to redistribute... well don't advertise them.
Question and answer below:
13. (QID:NE117) View the exhibit. A new TAC engineer comes to you for advice. The engineer wants to configure RIPv2-OSPF two-way redistribution while avoiding routing loops. Which two additions to the router B1 configuration should the engineer make?
access-list 40 deny 172.16.1.0 0.0.0.255
access-list 40 permit any
router rip
redistribute ospf 100 metric 5
distribute-list 40 out ospf 100
ip prefix-list rip-to-ospf permit 10.1.1.8/25 ge 26 le 28
route-map redis-rip deny 20
match ip address prefix-list rip-to-ospf
router ospf 100
redistribute rip route-map redis-rip subnets
access-list 15 deny 10.1.1.0 0.0.0.63
access-list 15 permit any
route-map redis-rip deny 10
match ip address 15
route-map redis-rip permit 20
router ospf 100
redistribute rip route-map redis-rip subnets
ip prefix-list rip_routes permit 172.16.1.16/25 ge 26 le 28
route-map redis-ospf deny 10
match ip address prefix-list rip_routes
router rip
redistribute ospf 10 route-map redis-ospf subnets
Correct Answer:
access-list 40 deny 172.16.1.0 0.0.0.255
access-list 40 permit any
router rip
redistribute ospf 100 metric 5
distribute-list 40 out ospf 100
access-list 15 deny 10.1.1.0 0.0.0.63
access-list 15 permit any
route-map redis-rip deny 10
match ip address 15
route-map redis-rip permit 20
router ospf 100
redistribute rip route-map redis-rip subnets
172.16.x.x network = RIPv2 routes
10.x.x.x network = OSPF routes
first off the access-list 15 statement is a denial and it is attached to a route-map that is also a denial statement. Followed by permit any statements. Which means that you are denying the access-list from being denied but permitting all other traffic. You can do that for sure but it won't accomplish any filtering. So because of that I crossed it off the list.
access-list 15 deny 10.1.1.0 0.0.0.63
access-list 15 permit any
route-map redis-rip deny 10
match ip address 15
route-map redis-rip permit 20
router ospf 100
redistribute rip route-map redis-rip subnets
Second of all access-list 40 statement is a denial of OSPF routes and that denial statement is incorporated into the RIP process denying these routes from being advertised out by rip. So uh... that defeats the purpose. Its like saying RIP, you see these OSPF routes that you are trying to redistribute... well don't advertise them.
Question and answer below:
13. (QID:NE117) View the exhibit. A new TAC engineer comes to you for advice. The engineer wants to configure RIPv2-OSPF two-way redistribution while avoiding routing loops. Which two additions to the router B1 configuration should the engineer make?
access-list 40 deny 172.16.1.0 0.0.0.255
access-list 40 permit any
router rip
redistribute ospf 100 metric 5
distribute-list 40 out ospf 100
ip prefix-list rip-to-ospf permit 10.1.1.8/25 ge 26 le 28
route-map redis-rip deny 20
match ip address prefix-list rip-to-ospf
router ospf 100
redistribute rip route-map redis-rip subnets
access-list 15 deny 10.1.1.0 0.0.0.63
access-list 15 permit any
route-map redis-rip deny 10
match ip address 15
route-map redis-rip permit 20
router ospf 100
redistribute rip route-map redis-rip subnets
ip prefix-list rip_routes permit 172.16.1.16/25 ge 26 le 28
route-map redis-ospf deny 10
match ip address prefix-list rip_routes
router rip
redistribute ospf 10 route-map redis-ospf subnets
Correct Answer:
access-list 40 deny 172.16.1.0 0.0.0.255
access-list 40 permit any
router rip
redistribute ospf 100 metric 5
distribute-list 40 out ospf 100
access-list 15 deny 10.1.1.0 0.0.0.63
access-list 15 permit any
route-map redis-rip deny 10
match ip address 15
route-map redis-rip permit 20
router ospf 100
redistribute rip route-map redis-rip subnets