KB ID 0001137
Problem
I’ve followed your Reverse Route Injection article and its not working? This email dropped in my mailbox a while back As it turns out the article I had written was for OSPF, and this chap was using EIGRP. So I ran it up with EIGRP as well to test.
Heres my topology, I want to inject the route for the remote site, into my internal EIGRP routing table.
Solution
Assuming EIGRP is already setup between the ASA and the LAN (i.e. Core Switch).
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ASA Petes-ASA# show run router ! router eigrp 20 no auto-summary network 10.1.0.0 255.255.0.0 passive-interface default no passive-interface inside redistribute static ! Switch Core-SW#show run | sec router router eigrp 20 network 10.1.0.0 0.0.255.255 network 10.2.0.0 0.0.255.255 network 10.3.0.0 0.0.255.255 no auto-summary
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Also assuming you already have a site to site VPN established and working.
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Petes-ASA# show cry isakmp IKEv1 SAs: Active SA: 1 Rekey SA: 0 (A tunnel will report 1 Active and 1 Rekey SA during rekey) Total IKE SA: 1 1 IKE Peer: 192.168.249.254 Type : L2L Role : responder Rekey : no State : MM_ACTIVE Petes-ASA# show cry ipsec sa interface: outside Crypto map tag: CRYPTO-MAP, seq num: 1, local addr: 192.168.253.254 access-list VPN-INTERESTING-TRAFIC extended permit ip 10.1.0.0 255.255.0.0 10.250.0.0 255.255.0.0 local ident (addr/mask/prot/port): (10.1.0.0/255.255.0.0/0/0) remote ident (addr/mask/prot/port): (10.250.0.0/255.255.0.0/0/0) current_peer: 192.168.249.254 #pkts encaps: 4, #pkts encrypt: 4, #pkts digest: 4 #pkts decaps: 4, #pkts decrypt: 4, #pkts verify: 4
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Show the Cryptomap, then add the RRI.
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Petes-ASA# show run crypto crypto ipsec ikev1 transform-set VPN-TRANSFORM esp-aes-256 esp-sha-hmac crypto map CRYPTO-MAP 1 match address VPN-INTERESTING-TRAFIC crypto map CRYPTO-MAP 1 set pfs crypto map CRYPTO-MAP 1 set peer 192.168.249.254 crypto map CRYPTO-MAP 1 set ikev1 transform-set VPN-TRANSFORM crypto map CRYPTO-MAP interface outside crypto ikev1 enable outside crypto ikev1 policy 10 authentication pre-share encryption aes-256 hash sha group 2 lifetime 86400 Petes-ASA# configure terminal Petes-ASA(config)# crypto map CRYPTO-MAP 1 set reverse-route Petes-ASA(config)#
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Create a ‘Prefix-List’ for the routes to inject (i.e the remote LAN at the other end of the VPN tunnel).
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Petes-ASA(config)# prefix-list PL-VPN-ROUTES description Route-Map For Injecting Remote VPN Routes Petes-ASA(config)# prefix-list PL-VPN-ROUTES seq 5 permit 10.250.0.0/16
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Create a ‘route-map’ to inject your prefix-list.
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Petes-ASA(config)# route-map RM-VPN-ROUTES permit 10 Petes-ASA(config-route-map)# match ip address prefix-list PL-VPN-ROUTE Petes-ASA(config-route-map)# set metric 1200 Petes-ASA(config-route-map)# exit Petes-ASA(config)# route-map RM-VPN-ROUTES deny 100
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With the tunnel up check your internal routing table;
Update: As pointed out by SteveH
You’ve missed the route-map off the re-distribute command,
router eigrp 20
redistribute static route-map RM-VPN-ROUTES
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Core-SW#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is 10.1.1.1 to network 0.0.0.0
10.0.0.0/16 is subnetted, 4 subnets
C 10.2.0.0 is directly connected, GigabitEthernet2/0
C 10.3.0.0 is directly connected, GigabitEthernet3/0
C 10.1.0.0 is directly connected, GigabitEthernet1/0
D EX 10.250.0.0 [170/28416] via 10.1.1.1, 00:00:02, GigabitEthernet1/0
D*EX 0.0.0.0/0 [170/28416] via 10.1.1.1, 00:00:02, GigabitEthernet1/0
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