Configurazione di una VPN multipoint dinamica con GRE over IPSec con EIGRP, NAT e CBAC
Sommario
Introduzione
In questo documento viene fornita una configurazione di esempio per la VPN dinamica multipoint (DMVPN) hub e spoke che utilizza un incapsulamento di routing generico (GRE) su IPSec con EIGRP (Enhanced Interior Gateway Routing Protocol), NAT (Network Address Translation) e CBAC (Context-Based Access Control).
Prerequisiti
Requisiti
Prima di poter stabilire un tunnel GRE (Multipoint GRE) e IPSec, è necessario definire un criterio IKE (Internet Key Exchange) utilizzando il comando crypto isakmp policy.
Nota: per ulteriori informazioni sui comandi menzionati in questo documento, usare lo strumento di ricerca dei comandi (solo utenti registrati).
Componenti usati
Le informazioni fornite in questo documento si basano sulle seguenti versioni software e hardware:
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Software Cisco IOS® versione 12.2(15)T1 sul router hub e versione 12.3(1.6) sui router spoke
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Cisco 3620 come router hub, due router Cisco 1720 e un router Cisco 3620 come router spoke
Le informazioni discusse in questo documento fanno riferimento a dispositivi usati in uno specifico ambiente di emulazione. Su tutti i dispositivi menzionati nel documento la configurazione è stata ripristinata ai valori predefiniti. Se la rete è operativa, valutare attentamente eventuali conseguenze derivanti dall'uso dei comandi.
Convenzioni
Per ulteriori informazioni sulle convenzioni usate, consultare il documento Cisco sulle convenzioni nei suggerimenti tecnici.
Configurazione
In questa sezione vengono presentate le informazioni necessarie per configurare le funzionalità descritte più avanti nel documento.
Nota: per ulteriori informazioni sui comandi menzionati in questo documento, usare lo strumento di ricerca dei comandi (solo utenti registrati).
Esempio di rete
Questo documento utilizza le impostazioni di rete mostrate nel diagramma sottostante.
Configurazioni
Questo documento utilizza le configurazioni mostrate di seguito.
| Hub - 3620-B |
|---|
3620-B#write terminal Building configuration... Current configuration : 2607 bytes ! version 12.2 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname 3620-B ! logging queue-limit 100 ! memory-size iomem 10 ip subnet-zero ! ! ip cef no ip domain lookup ! !--- This is the CBAC configuration and what to inspect. !--- This will be applied outbound on the external interface. ip inspect name in2out rcmd ip inspect name in2out ftp ip inspect name in2out tftp ip inspect name in2out tcp timeout 43200 ip inspect name in2out http ip inspect name in2out udp ip audit po max-events 100 ! ! ! !--- Create an Internet Security Association and Key Management !--- Protocol (ISAKMP) policy for Phase 1 negotiations. ! crypto isakmp policy 5 authentication pre-share group 2 !--- Add dynamic pre-shared key. !--- Here "dmvpn" is the word that is used as the key. crypto isakmp key dmvpnkey address 0.0.0.0 0.0.0.0 crypto isakmp nat keepalive 20 ! ! !--- Create the Phase 2 policy for actual data encryption. crypto ipsec transform-set dmvpnset esp-3des esp-sha-hmac ! !--- Create an IPSec profile to be applied dynamically !--- to the GRE over IPSec tunnels. crypto ipsec profile dmvpnprof set transform-set dmvpnset ! ! no voice hpi capture buffer no voice hpi capture destination ! ! mta receive maximum-recipients 0 ! ! !--- This is the inside interface. interface Loopback1 ip address 192.168.117.1 255.255.255.0 ip nat inside ! !--- This is the mGRE interface for dynamic GRE tunnels. interface Tunnel1 description MULTI-POINT GRE TUNNEL for BRANCHES bandwidth 1000 ip address 172.16.0.1 255.255.255.0 no ip redirects ip mtu 1400 ip nhrp authentication dmvpn ip nhrp map multicast dynamic ip nhrp network-id 99 ip nhrp holdtime 300 no ip split-horizon eigrp 1 no ip mroute-cache delay 1000 tunnel source FastEthernet0/0 tunnel mode gre multipoint tunnel key 100000 tunnel protection ipsec profile dmvpnprof ! !--- This is the outside interface. interface FastEthernet0/0 ip address 14.24.117.1 255.255.0.0 ip nat outside ip access-group 100 in ip inspect in2out out no ip mroute-cache duplex auto speed auto ! interface Serial0/0 no ip address shutdown clockrate 2000000 no fair-queue ! interface FastEthernet0/1 no ip address no ip mroute-cache duplex auto speed auto ! !--- Enable a routing protocol to send/receive dynamic !--- updates about the private networks over the tunnels. router eigrp 1 network 172.16.0.0 0.0.0.255 network 192.168.117.0 no auto-summary ! !--- Perform NAT on local traffic !--- going directly out FastEthernet0/0. ip nat inside source list 110 interface FastEthernet0/0 overload ip http server no ip http secure-server ip classless ip route 0.0.0.0 0.0.0.0 14.24.1.1 ip route 2.0.0.0 255.0.0.0 14.24.121.1 ! ! ! !--- Allow ISAKMP, ESP, and GRE traffic inbound. !--- CBAC will open other inbound access as needed. access-list 100 permit udp any host 14.24.117.1 eq 500 access-list 100 permit esp any host 14.24.117.1 access-list 100 permit gre any host 14.24.117.1 access-list 100 deny ip any any access-list 110 permit ip 192.168.117.0 0.0.0.255 any ! ! call rsvp-sync ! ! mgcp profile default ! dial-peer cor custom ! ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! ! end 3620-B# |
| Raggio 1 - 3620-A |
|---|
3620-A#write terminal Building configuration... Current configuration : 2559 bytes ! version 12.2 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname 3620-A ! boot system flash slot0:c3620-ik9o3s7-mz.122-15.T1.bin logging queue-limit 100 ! memory-size iomem 15 ip subnet-zero ! ! ip cef no ip domain lookup ! !--- This is the CBAC configuration and what to inspect. !--- This will be applied outbound on the external interface. ip inspect name in2out rcmd ip inspect name in2out tftp ip inspect name in2out udp ip inspect name in2out tcp timeout 43200 ip inspect name in2out realaudio ip inspect name in2out vdolive ip inspect name in2out netshow ip audit po max-events 100 ! ! ! !--- Create an ISAKMP policy for !--- Phase 1 negotiations. crypto isakmp policy 5 authentication pre-share group 2 !--- Add dynamic pre-shared key. crypto isakmp key dmvpnkey address 0.0.0.0 0.0.0.0 ! ! !--- Create the Phase 2 policy for actual data encryption. crypto ipsec transform-set dmvpnset esp-3des esp-sha-hmac ! !--- Create an IPSec profile to be applied dynamically !--- to the GRE over IPSec tunnels. crypto ipsec profile dmvpnprof set transform-set dmvpnset ! ! no voice hpi capture buffer no voice hpi capture destination ! ! mta receive maximum-recipients 0 ! ! !--- This is the inside interface. interface Loopback1 ip address 192.168.118.1 255.255.255.0 ip nat inside ! !--- This is the mGRE interface for dynamic GRE tunnels. interface Tunnel1 description HOST DYNAMIC TUNNEL bandwidth 1000 ip address 172.16.0.2 255.255.255.0 no ip redirects ip mtu 1400 ip nhrp authentication dmvpn ip nhrp map 172.16.0.1 14.24.117.1 ip nhrp map multicast 14.24.117.1 ip nhrp network-id 99 ip nhrp holdtime 300 ip nhrp nhs 172.16.0.1 no ip mroute-cache delay 1000 tunnel source Ethernet0/0 tunnel mode gre multipoint tunnel key 100000 tunnel protection ipsec profile dmvpnprof ! !--- This is the outside interface. interface Ethernet0/0 ip address 14.24.118.1 255.255.0.0 ip nat outside ip inspect in2out out ip access-group 100 in no ip mroute-cache half-duplex ! interface Ethernet0/1 no ip address half-duplex ! interface Ethernet0/2 no ip address shutdown half-duplex ! interface Ethernet0/3 no ip address shutdown half-duplex ! !--- Enable a routing protocol to send/receive dynamic !--- updates about the private networks over the tunnel. router eigrp 1 network 172.16.0.0 0.0.0.255 network 192.168.118.0 no auto-summary ! !--- Perform NAT on local traffic !--- going directly out Ethernet0/0. ip nat inside source list 110 interface Ethernet0/0 overload ip http server no ip http secure-server ip classless ip route 0.0.0.0 0.0.0.0 14.24.1.1 ! ! !--- Allow ISAKMP, ESP, and GRE traffic inbound. !--- CBAC will open inbound access as needed. access-list 100 permit udp any host 14.24.118.1 eq 500 access-list 100 permit esp any host 14.24.118.1 access-list 100 permit gre any host 14.24.118.1 access-list 100 deny ip any any access-list 110 permit ip 192.168.118.0 0.0.0.255 any ! ! call rsvp-sync ! ! mgcp profile default ! dial-peer cor custom ! ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! ! end 3620-A# |
| Raggio 2 - 1720-b |
|---|
1720-b#write terminal Building configuration... Current configuration : 2543 bytes ! version 12.2 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname 1720-b ! boot system flash flash:c1700-ny-mz.122-8.YJ logging queue-limit 100 enable password cisco ! username 7206-B password 0 cisco ip subnet-zero ! ! no ip domain lookup ! ip cef !--- This is the CBAC configuration and what to inspect. !--- This will be applied outbound on the external interface. ip inspect name in2out rcmd ip inspect name in2out tftp ip inspect name in2out udp ip inspect name in2out tcp timeout 43200 ip inspect name in2out realaudio ip inspect name in2out vdolive ip inspect name in2out netshow ip audit po max-events 100 ! ! vpdn-group 1 request-dialin protocol pppoe ! ! !--- Create an ISAKMP policy for !--- Phase 1 negotiations. crypto isakmp policy 5 authentication pre-share group 2 !--- Add dynamic pre-shared key. crypto isakmp key dmvpnkey address 0.0.0.0 0.0.0.0 ! ! !--- Create the Phase 2 policy for actual data encryption. crypto ipsec transform-set dmvpnset esp-3des esp-sha-hmac ! !--- Create an IPSec profile to be applied dynamically !--- to the GRE over IPSec tunnels. crypto ipsec profile dmvpnprof set transform-set dmvpnset ! ! !--- This is the inside interface. interface Loopback1 ip address 192.168.116.1 255.255.255.0 ip nat inside ! !--- This is the mGRE interface for dynamic GRE tunnels. interface Tunnel1 description HOST DYNAMIC TUNNEL bandwidth 1000 ip address 172.16.0.3 255.255.255.0 no ip redirects ip mtu 1400 ip nhrp authentication dmvpn ip nhrp map 172.16.0.1 14.24.117.1 ip nhrp map multicast 14.24.117.1 ip nhrp network-id 99 ip nhrp holdtime 300 ip nhrp nhs 172.16.0.1 no ip mroute-cache delay 1000 tunnel source Dialer1 tunnel mode gre multipoint tunnel key 100000 tunnel protection ipsec profile dmvpnprof ! interface Ethernet0 no ip address half-duplex ! interface FastEthernet0 no ip address no ip mroute-cache speed auto pppoe enable pppoe-client dial-pool-number 1 ! !--- This is the outside interface. interface Dialer1 ip address 2.2.2.10 255.255.255.0 ip inspect in2out out ip access-group 100 in encapsulation ppp dialer pool 1 dialer-group 1 ppp authentication pap chap callin ! !--- Enable a routing protocol to send/receive dynamic !--- updates about the private networks. router eigrp 1 network 172.16.0.0 0.0.0.255 network 192.168.116.0 no auto-summary ! !--- Perform NAT on local traffic !--- going directly out Dialer1. ip nat inside source list 110 interface Dialer1 overload ip classless ip route 0.0.0.0 0.0.0.0 Dialer1 no ip http server no ip http secure-server ! ! ! !--- Allow ISAKMP, ESP, and GRE traffic inbound. !--- CBAC will open inbound access as needed. access-list 100 permit udp any host 14.24.116.1 eq 500 access-list 100 permit esp any host 14.24.116.1 access-list 100 permit gre any host 14.24.116.1 access-list 100 deny ip any any access-list 110 permit ip 192.168.116.0 0.0.0.255 any dialer-list 1 protocol ip permit ! ! ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! no scheduler allocate end 1720-b# |
| Raggio 3 - 1720-A |
|---|
1720-A#write terminal Building configuration... Current configuration : 1770 bytes ! version 12.2 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname 1720-A ! logging queue-limit 100 ! memory-size iomem 25 ip subnet-zero ! ! ! ip cef !--- This is the CBAC configuration and what to inspect. !--- This will be applied outbound on the external interface. ip inspect name in2out rcmd ip inspect name in2out tftp ip inspect name in2out udp ip inspect name in2out tcp timeout 43200 ip inspect name in2out realaudio ip inspect name in2out vdolive ip inspect name in2out netshow ip audit po max-events 100 ! ! !--- Create an ISAKMP policy for !--- Phase 1 negotiations. crypto isakmp policy 5 authentication pre-share group 2 !--- Add dynamic pre-shared key. crypto isakmp key dmvpnkey address 0.0.0.0 0.0.0.0 ! ! !--- Create the Phase 2 policy for actual data encryption. crypto ipsec transform-set dmvpnset esp-3des esp-sha-hmac ! !--- Create an IPSec profile to be applied dynamically !--- to the GRE over IPSec tunnels. crypto ipsec profile dmvpnprof set transform-set dmvpnset ! ! !--- This is the inside interface. interface Loopback1 ip address 192.168.120.1 255.255.255.0 ip nat inside ! !--- This is the mGRE interface for dynamic GRE tunnels. interface Tunnel1 description HOST DYNAMIC TUNNEL bandwidth 1000 ip address 172.16.0.4 255.255.255.0 no ip redirects ip mtu 1400 ip nhrp authentication dmvpn ip nhrp map 172.16.0.1 14.24.117.1 ip nhrp map multicast 14.24.117.1 ip nhrp network-id 99 ip nhrp holdtime 300 ip nhrp nhs 172.16.0.1 no ip mroute-cache delay 1000 tunnel source FastEthernet0 tunnel mode gre multipoint tunnel key 100000 tunnel protection ipsec profile dmvpnprof ! interface Ethernet0 no ip address no ip mroute-cache half-duplex ! !--- This is the outside interface. interface FastEthernet0 ip address 14.24.120.1 255.255.0.0 ip nat outside ip inspect in2out out ip access-group 100 in no ip mroute-cache speed auto ! !--- Enable a routing protocol to send/receive dynamic !--- updates about the private networks. router eigrp 1 network 172.16.0.0 0.0.0.255 network 192.168.120.0 no auto-summary ! !--- Perform NAT on local traffic !--- going directly out FastEthernet0. ip nat inside source list 110 interface FastEthernet0 overload ip classless ip route 0.0.0.0 0.0.0.0 14.24.1.1 no ip http server no ip http secure-server ! ! ! !--- Allow ISAKMP, ESP, and GRE traffic inbound. !--- CBAC will open inbound access as needed. access-list 100 permit udp any host 14.24.116.1 eq 500 access-list 100 permit esp any host 14.24.116.1 access-list 100 permit gre any host 14.24.116.1 access-list 100 deny ip any any access-list 110 permit ip 192.168.120.0 0.0.0.255 any ! ! ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! no scheduler allocate end 1720-A# |
Verifica
Le informazioni contenute in questa sezione permettono di verificare che la configurazione funzioni correttamente.
Alcuni comandi show sono supportati dallo strumento Output Interpreter (solo utenti registrati); lo strumento permette di visualizzare un'analisi dell'output del comando show.
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show crypto isakmp sa: visualizza lo stato dell'associazione di sicurezza ISAKMP.
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show crypto engine connections active: visualizza il totale di crittografia/decrittografia per SA.
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show crypto ipsec sa: visualizza le statistiche sui tunnel attivi.
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show ip route: visualizza la tabella di routing.
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show ip eigrp neighbors: visualizza i router adiacenti EIGRP.
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show ip nhrp: visualizza la cache NHRP (IP Next Hop Resolution Protocol), facoltativamente limitata alle voci di cache dinamica o statica per un'interfaccia specifica.
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show crypto socket: visualizza la tabella dei socket di crittografia tra NHRP e IPSec.
Risoluzione dei problemi
Le informazioni contenute in questa sezione permettono di risolvere i problemi relativi alla configurazione.
Comandi per la risoluzione dei problemi
Nota: prima di usare i comandi di debug, consultare le informazioni importanti sui comandi di debug.
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debug crypto ipsec: visualizza gli eventi IPSec.
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debug crypto isakmp: visualizza i messaggi sugli eventi IKE.
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debug crypto engine: visualizza le informazioni provenienti dal crypto engine.
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debug crypto socket: visualizza le informazioni sulla tabella socket tra NHRP e IPSec.
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debug nhrp: visualizza informazioni sugli eventi NHRP.
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debug nhrp packet: visualizza le informazioni sui pacchetti NHRP.
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debug tunnel protection: visualizza le informazioni sui tunnel GRE dinamici.
Per ulteriori informazioni sulla risoluzione dei problemi relativi a IPSec, consultare il documento sulla risoluzione dei problemi relativi alla protezione IP - descrizione e uso dei comandi di debug.
Informazioni correlate
Cronologia delle revisioni
| Revisione | Data di pubblicazione | Commenti |
|---|---|---|
1.0 |
14-Jan-2008 |
Versione iniziale |
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