Configurazione delle funzionalità di alta disponibilità per le VPN IPSec da sito a sito
Sommario
Introduzione
In questo documento vengono descritte le nuove funzionalità per l'elevata disponibilità delle reti VPN IPSec da sito a sito. Il protocollo HSRP (Hot Standby Router Protocol) viene spesso utilizzato per tenere traccia dello stato dell'interfaccia dei router e ottenere il failover tra i router. Tuttavia, poiché non esiste alcuna correlazione interna tra IPSec e HSRP, HSRP non tiene traccia dello stato delle associazioni di protezione IPSec e IPSec richiede schemi per la sincronizzazione con il failover HSRP quando questo si verifica. Di seguito sono riportati alcuni degli schemi utilizzati per creare un collegamento più stretto tra IPSec e HSRP:
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Il comando keepalive IKE (Internet Key Exchange) consente a IPSec di rilevare il failover HSRP in tempo.
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La mappa crittografica applicata a un'interfaccia di router specifica è collegata al gruppo HSRP già configurato su tale interfaccia in modo che IPSec riconosca la configurazione HSRP. In questo modo IPSec potrà inoltre utilizzare l'indirizzo IP virtuale HSRP come identità ISAKMP (Internet Security Association and Key Management Protocol) dei router HSRP.
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La funzionalità di reverse route injection (RRI) viene utilizzata per consentire l'aggiornamento dinamico delle informazioni di routing durante il failover di HSRP e IPSec.
Nota: questo documento descrive come usare il protocollo HSRP (Hot Standby Router Protocol) con VPN. HSRP viene inoltre utilizzato per tenere traccia dei collegamenti ISP non riusciti. Per configurare i collegamenti ISP ridondanti sui router, consultare il documento sull'analisi dei livelli di servizio IP con l'operazione echo ICMP. Qui il dispositivo di origine è il router e il dispositivo di destinazione il dispositivo ISP.
Prerequisiti
Requisiti
Non sono previsti prerequisiti specifici per questo documento.
Componenti usati
Le informazioni fornite in questo documento si basano sulle seguenti versioni software e hardware:
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Cisco serie 7200 Router
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Software Cisco IOS® versione 12.3(7)T1, c7200-a3jk9s-mz.123-7.T1
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 questa sezione, usare lo strumento di ricerca dei comandi (solo utenti registrati).
Esempio di rete
Nel documento viene usata questa impostazione di rete:
Configurazioni
Nel documento vengono usate queste configurazioni:
| Configurazione Cisco VPN 7200 |
|---|
vpn7200#show run Building configuration... Current configuration : 1854 bytes ! version 12.2 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname vpn7200 ! ! ip subnet-zero ip cef !--- Defines ISAKMP policy and IKE pre-shared key for !--- IKE authentication. Note that 172.16.172.53 is the !--- HSRP virtual IP address of the remote HSRP routers. crypto isakmp policy 1 hash md5 authentication pre-share crypto isakmp key cisco123 address 172.16.172.53 !--- IKE keepalive to detect the IPSec liveness of the remote !--- VPN router. When HSRP failover happens, IKE keepalive !--- will detect the HSRP router switchover. crypto isakmp keepalive 10 ! ! crypto ipsec transform-set myset esp-des esp-md5-hmac !--- Defines crypto map. Note that the peer address is the !--- HSRP virtual IP address of the remote HSRP routers. crypto map vpn 10 ipsec-isakmp set peer 172.16.172.53 set transform-set myset match address 101 ! interface Loopback0 ip address 20.1.1.1 255.255.255.255 ! interface FastEthernet0/0 ip address 10.48.66.66 255.255.254.0 duplex full speed 100 ! interface FastEthernet0/1 ip address 172.16.172.69 255.255.255.240 duplex full speed 100 crypto map vpn ! ip classless ip route 10.1.1.0 255.255.255.0 172.16.172.65 ip route 99.99.99.99 255.255.255.255 172.16.172.65 ip route 172.16.172.48 255.255.255.240 172.16.172.65 no ip http server ! access-list 101 permit ip 20.1.1.0 0.0.0.255 10.1.1.0 0.0.0.255 access-list 101 permit ip 20.1.1.0 0.0.0.255 host 99.99.99.99 ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! end |
| Configurazione Cisco 7204VXR-1 |
|---|
7204VXR-1#show run Building configuration... Current configuration : 1754 bytes ! version 12.3 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname 7204VXR-1 ! boot-start-marker boot-end-marker ! ! no aaa new-model ip subnet-zero ! ! no ip domain lookup ! ! ip cef! !--- Defines ISAKMP policy. crypto isakmp policy 1 hash md5 authentication pre-share crypto isakmp key cisco123 address 172.16.172.69 crypto isakmp keepalive 10 ! ! crypto ipsec transform-set myset esp-des esp-md5-hmac !--- Defines crypto map. Note that "reverse-route" !--- turns on the RRI feature. crypto map vpn 10 ipsec-isakmp set peer 172.16.172.69 set transform-set myset match address 101 reverse-route ! ! !--- Define HSRP under the interface. HSRP will track the !--- internal interface as well. HSRP group name must be !--- defined here and will be used for IPSec configuration. !--- The "redundancy" keyword in the crypto map command !--- specifies the HSRP group to which IPSec will couple. !--- In normal circumstances, this router will be the HSRP !--- primary router since it has higher priority than the !--- other HSRP router. interface FastEthernet0/0 ip address 172.16.172.52 255.255.255.240 duplex full speed 100 standby 1 ip 172.16.172.53 standby 1 priority 200 standby 1 preempt standby 1 name VPNHA standby 1 track FastEthernet0/1 150 crypto map vpn redundancy VPNHA ! interface FastEthernet0/1 ip address 10.1.1.1 255.255.255.0 duplex full speed 100 ! interface ATM1/0 no ip address shutdown no atm ilmi-keepalive ! interface FastEthernet3/0 no ip address shutdown duplex half ! interface ATM6/0 no ip address shutdown no atm ilmi-keepalive !--- Define dynamic routing protocol and re-distribute static !--- route. This enables dynamic routing information update !--- during the HSRP/IPSec failover. All the "VPN routes" !--- that are injected in the routing table by RRI as static !--- routes will be redistributed to internal networks. ! router ospf 1 log-adjacency-changes redistribute static subnets network 10.1.1.0 0.0.0.255 area 0 ! ip classless ip route 172.16.172.64 255.255.255.240 172.16.172.49 no ip http server no ip http secure-server ! ! !--- Defines VPN traffic. The destination IP subnet will be !--- injected into the routing table as static routes by RRI. access-list 101 permit ip 10.1.1.0 0.0.0.255 20.1.1.0 0.0.0.255 access-list 101 permit ip host 99.99.99.99 20.1.1.0 0.0.0.255 ! line con 0 exec-timeout 0 0 stopbits 1 line aux 0 stopbits 1 line vty 0 4 ! ! ! end |
| Configurazione Cisco 7204VXR-2 |
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7204VXR-2#show run Building configuration... Current configuration : 2493 bytes ! version 12.3 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname 7204VXR-2 ! boot-start-marker boot system flash disk1:c7200-a3jk9s-mz.123-7.T1 boot-end-marker ! no aaa new-model ip subnet-zero ! ! no ip domain lookup ip host rund 10.48.92.61 ! ! ip cef ! crypto isakmp policy 1 hash md5 authentication pre-share crypto isakmp key cisco123 address 172.16.172.69 crypto isakmp keepalive 10 ! ! crypto ipsec transform-set myset esp-des esp-md5-hmac ! crypto map vpn 10 ipsec-isakmp set peer 172.16.172.69 set transform-set myset match address 101 reverse-route ! !--- During normal operational conditions this router !--- will be the standby router. interface FastEthernet0/0 ip address 172.16.172.54 255.255.255.240 ip directed-broadcast duplex full standby 1 ip 172.16.172.53 standby 1 preempt standby 1 name VPNHA standby 1 track FastEthernet1/0 crypto map vpn redundancy VPNHA ! interface FastEthernet1/0 ip address 10.1.1.2 255.255.255.0 ip directed-broadcast duplex full ! interface FastEthernet3/0 ip address 10.48.67.182 255.255.254.0 ip directed-broadcast shutdown duplex full ! router ospf 1 log-adjacency-changes redistribute static subnets network 10.1.1.0 0.0.0.255 area 0 ! ip classless ip route 172.16.172.64 255.255.255.240 172.16.172.49 no ip http server no ip http secure-server ! ! ! access-list 101 permit ip 10.1.1.0 0.0.0.255 20.1.1.0 0.0.0.255 access-list 101 permit ip host 99.99.99.99 20.1.1.0 0.0.0.255 ! line con 0 exec-timeout 0 0 transport preferred all transport output all stopbits 1 line aux 0 transport preferred all transport output all stopbits 1 line vty 0 4 login transport preferred all transport input all transport output all ! ! ! end |
| Configurazione di Cisco 7206-1 |
|---|
7206-1#show run Building configuration... Current configuration : 1551 bytes ! version 12.2 no service pad service timestamps debug datetime msec localtime service timestamps log datetime msec localtime no service password-encryption ! hostname 7206-1 ! ip subnet-zero no ip source-route ip cef ! interface Loopback0 ip address 99.99.99.99 255.255.255.255 ! interface FastEthernet0/0 shutdown duplex full speed 100 ! !--- Define dynamic routing protocol. All the "VPN routes" !--- will be learned and updated dynamically from upstream HSRP !--- routers using the dynamic routing protocols. interface FastEthernet0/1 ip address 10.1.1.3 255.255.255.0 duplex full speed 100 ! router ospf 1 log-adjacency-changes passive-interface Loopback0 network 10.1.1.0 0.0.0.255 area 0 network 99.99.99.99 0.0.0.0 area 0 ! ip classless no ip http server ! ! ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! end |
Come funziona?
In questo esempio viene illustrato il funzionamento congiunto del failover di HSRP e IPSec tramite l'installazione e la configurazione descritte in precedenza. In questo caso di studio vengono evidenziati tre aspetti:
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Failover HSRP a causa di un errore dell'interfaccia.
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Modalità di esecuzione del failover IPSec dopo il failover HSRP. Come si può vedere, il failover IPSec sarà "stateless".
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Modalità di aggiornamento dinamico e propagazione alle reti interne delle modifiche delle informazioni di routing causate dal failover.
Nota: il traffico di prova qui è costituito dai pacchetti Internet Control Message Protocol (ICMP) tra l'indirizzo IP di loopback di Cisco 7206-1 (99.99.99.99) e l'indirizzo IP di loopback di Cisco VPN 7200 (20.1.1.1) e simula il traffico VPN tra i due siti.
Circostanza normale (prima del failover)
Prima del failover, Cisco 7204VXR-1 è il router HSRP principale e Cisco VPN 7200 ha associazioni di protezione IPSec con Cisco 7204VXR-1.
Quando la mappa crittografica è configurata sull'interfaccia, la funzione RRI immette una route VPN corrispondente all'elenco di controllo di accesso (ACL) IPSec configurato e all'istruzione di comando set peer nella mappa crittografica. Questo router viene aggiunto alla tabella di routing del router HSRP 7204VXR-1 primario.
L'output del comando debug crypto ipsec indica che la route VPN 20.1.1/24 è stata aggiunta alla base delle informazioni di routing (RIB).
IPSEC(rte_mgr): VPN Route Added 20.1.1.0 255.255.255.0 via 172.16.172.69 in IP DEFAULT TABLE
La tabella di routing sul router HSRP primario restituisce una route statica a 20.1.1/24, che viene ridistribuita da Open Shortest Path First (OSPF) al router HSRP secondario, 7204VXR-2, e al router interno, 7206-1.
L'hop successivo per la route VPN 20.1.1/24 iniettata come route statica nel RIB del router 7204VXR-1 è l'indirizzo IP del peer di crittografia remoto. In questo caso, l'hop successivo per la route VPN 20.1.1/24 è 172.16.172.69. L'indirizzo IP dell'hop successivo della route VPN viene risolto tramite una ricerca ricorsiva della route, come mostrato nella tabella di inoltro Cisco Express:
7204VXR-1#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 not set
99.0.0.0/32 is subnetted, 1 subnets
O 99.99.99.99 [110/2] via 10.1.1.3, 00:11:21, FastEthernet0/1
20.0.0.0/24 is subnetted, 1 subnets
S 20.1.1.0 [1/0] via 172.16.172.69
172.16.0.0/28 is subnetted, 2 subnets
C 172.16.172.48 is directly connected, FastEthernet0/0
S 172.16.172.64 [1/0] via 172.16.172.49
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/24 is directly connected, FastEthernet0/1
S 10.48.66.0/23 [1/0] via 10.1.1.2
7204VXR-1#show ip cef 20.1.1.0 detail
20.1.1.0/24, version 66, epoch 0, cached adjacency 172.16.172.49
0 packets, 0 bytes
via 172.16.172.69, 0 dependencies, recursive
next hop 172.16.172.49, FastEthernet0/0 via 172.16.172.64/28
valid cached adjacency
Il router HSRP secondario e il router interno 7206-1 apprendono questa route VPN tramite OSPF/. Gli amministratori di rete non devono immettere manualmente la route statica. Inoltre, le modifiche di routing causate dal failover vengono aggiornate in modo dinamico.
7204VXR-2#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 10.48.66.1 to network 0.0.0.0
99.0.0.0/32 is subnetted, 1 subnets
O 99.99.99.99 [110/2] via 10.1.1.3, 00:29:31, FastEthernet1/0
20.0.0.0/24 is subnetted, 1 subnets
O E2 20.1.1.0 [110/20] via 10.1.1.1, 00:11:06, FastEthernet1/0
172.16.0.0/28 is subnetted, 2 subnets
C 172.16.172.48 is directly connected, FastEthernet0/0
S 172.16.172.64 [1/0] via 172.16.172.49
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/24 is directly connected, FastEthernet1/0
C 10.48.66.0/23 is directly connected, FastEthernet3/0
S* 0.0.0.0/0 [1/0] via 10.48.66.1
7206-1#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 not set
99.0.0.0/32 is subnetted, 1 subnets
C 99.99.99.99 is directly connected, Loopback0
20.0.0.0/24 is subnetted, 1 subnets
O E2 20.1.1.0 [110/20] via 10.1.1.1, 00:14:01, FastEthernet0/1
172.16.0.0/28 is subnetted, 1 subnets
O E2 172.16.172.64 [110/20] via 10.1.1.1, 00:32:21, FastEthernet0/1
[110/20] via 10.1.1.2, 00:32:21, FastEthernet0/1
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/24 is directly connected, FastEthernet0/1
O E2 10.48.66.0/23 [110/20] via 10.1.1.2, 00:32:22, FastEthernet0/1
Il router 7204VXR-1 è il router HSRP primario che segue l'interfaccia interna Fa0/1.
7204VXR-1#show standby FastEthernet0/0 - Group 1 State is Active 2 state changes, last state change 03:21:20 Virtual IP address is 172.16.172.53 Active virtual MAC address is 0000.0c07.ac01 Local virtual MAC address is 0000.0c07.ac01 (v1 default) Hello time 3 sec, hold time 10 sec Next hello sent in 0.172 secs Preemption enabled Active router is local Standby router is 172.16.172.54, priority 100 (expires in 7.220 sec) Priority 200 (configured 200) Track interface FastEthernet0/1 state Up decrement 150 IP redundancy name is "VPNHA" (cfgd)
È possibile utilizzare il comando show track per visualizzare un elenco di tutti gli oggetti rilevati da HSRP.
7204VXR-1#show track Track 1 (via HSRP) Interface FastEthernet0/1 line-protocol Line protocol is Up 1 change, last change 03:18:22 Tracked by: HSRP FastEthernet0/0 1
Il router 7204VXR-2 è il router HSRP in standby. In condizioni operative normali, questo dispositivo segue l'interfaccia interna Fa1/0.
7204VXR-2#show standby FastEthernet0/0 - Group 1 State is Standby 1 state change, last state change 02:22:30 Virtual IP address is 172.16.172.53 Active virtual MAC address is 0000.0c07.ac01 Local virtual MAC address is 0000.0c07.ac01 (v1 default) Hello time 3 sec, hold time 10 sec Next hello sent in 0.096 secs Preemption enabled Active router is 172.16.172.52, priority 200 (expires in 7.040 sec) Standby router is local Priority 100 (default 100) Track interface FastEthernet1/0 state Up decrement 10 IP redundancy name is "VPNHA" (cfgd)
Questi comandi show relativi a IPSec restituiscono un output sul router Cisco VPN 7200 che dimostra le associazioni di protezione ISAKMP e IPSec tra Cisco VPN 7200 e il router HSRP primario, Cisco 7204VXR-1.
7204VXR-1#show crypto isakmp sa detail
Codes: C - IKE configuration mode, D - Dead Peer Detection
K - Keepalives, N - NAT-traversal
X - IKE Extended Authentication
psk - Preshared key, rsig - RSA signature
renc - RSA encryption
C-id Local Remote I-VRF Encr Hash Auth DH Lifetime Cap.
1 172.16.172.53 172.16.172.69 des md5 psk 1 23:49:52 K
Connection-id:Engine-id = 1:1(software)
7204VXR-1#show crypto ipsec sa
interface: FastEthernet0/0
Crypto map tag: vpn, local addr. 172.16.172.53
protected vrf:
local ident (addr/mask/prot/port): (99.99.99.99/255.255.255.255/0/0)
remote ident (addr/mask/prot/port): (20.1.1.0/255.255.255.0/0/0)
current_peer: 172.16.172.69:500
PERMIT, flags={origin_is_acl,}
#pkts encaps: 5, #pkts encrypt: 5, #pkts digest: 5
#pkts decaps: 5, #pkts decrypt: 5, #pkts verify: 5
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0
#pkts not decompressed: 0, #pkts decompress failed: 0
#send errors 0, #recv errors 0
local crypto endpt.: 172.16.172.53, remote crypto endpt.: 172.16.172.69
path mtu 1500, media mtu 1500
current outbound spi: 44E0B22B
inbound esp sas:
spi: 0x5B23F22E(1529082414)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2000, flow_id: 1, crypto map: vpn
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4504144/2949)
ike_cookies: B57A9DC9 FA2D627B F70FEDF6 FAAF9E34
IV size: 8 bytes
replay detection support: Y
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x44E0B22B(1155576363)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2001, flow_id: 2, crypto map: vpn
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4504145/2949)
ike_cookies: B57A9DC9 FA2D627B F70FEDF6 FAAF9E34
IV size: 8 bytes
replay detection support: Y
outbound ah sas:
outbound pcp sas:
vpn7200#show crypto isakmp sa
dst src state conn-id slot
172.16.172.53 172.16.172.69 QM_IDLE 1 0
7204VXR-2#show crypto ipsec sa
interface: FastEthernet0/1
Crypto map tag: vpn, local addr. 172.16.172.69
local ident (addr/mask/prot/port): (20.1.1.0/255.255.255.0/0/0)
remote ident (addr/mask/prot/port): (99.99.99.99/255.255.255.255/0/0)
current_peer: 172.16.172.53
PERMIT, flags={origin_is_acl,}
#pkts encaps: 10, #pkts encrypt: 10, #pkts digest 10
#pkts decaps: 10, #pkts decrypt: 10, #pkts verify 10
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0
#send errors 5, #recv errors 0
local crypto endpt.: 172.16.172.69, remote crypto endpt.: 172.16.172.53
path mtu 1500, ip mtu 1500
current outbound spi: 5B23F22E
inbound esp sas:
spi: 0x44E0B22B(1155576363)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2029, flow_id: 1, crypto map: vpn
sa timing: remaining key lifetime (k/sec): (4607997/2824)
IV size: 8 bytes
replay detection support: Y
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x5B23F22E(1529082414)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2030, flow_id: 2, crypto map: vpn
sa timing: remaining key lifetime (k/sec): (4607998/2824)
IV size: 8 bytes
replay detection support: Y
outbound ah sas:
outbound pcp sas:
Dopo il failover di HSRP e IPSec
Il failover è stato attivato chiudendo Fa0/0 su Cisco 7204VXR-1. Si verificherà un comportamento simile se l'altra interfaccia, Fa0/1, è inattiva perché anche HSRP tiene traccia dello stato di questa interfaccia.
Quando Cisco VPN 7200 non riceve risposta ai pacchetti IKE keepalive inviati al router HSRP primario, il router interrompe le associazioni di protezione IPSec.
Questo output del comando debug crypto isakmp mostra come IKE keepalive rileva l'interruzione del router primario:
ISAKMP (0:1): received packet from 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): processing HASH payload. message ID = 1585108592 ISAKMP (0:1): processing NOTIFY ITS_ALIVE protocol 1 spi 0, message ID = 1585108592, sa = 61C3E754 ISAKMP (0:1): sending packet to 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): purging node -1484552386 ISAKMP (0:1): deleting node 1585108592 error FALSE reason "informational (in) state 1" ISAKMP (0:1): purging node 642343711 ISAKMP (0:1): sending packet to 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): purging node -523181212 ISAKMP (0:1): purging node -2089541867 ISAKMP (0:1): incrementing error counter on sa: PEERS_ALIVE_TIMER ISAKMP (0:1): sending packet to 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): purging node 1671177686 ISAKMP (0:1): incrementing error counter on sa: PEERS_ALIVE_TIMER ISAKMP (0:1): sending packet to 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): purging node 1706520344 ISAKMP (0:1): incrementing error counter on sa: PEERS_ALIVE_TIMER ISAKMP (0:1): sending packet to 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): purging node 503375209 ISAKMP (0:1): incrementing error counter on sa: PEERS_ALIVE_TIMER ISAKMP (0:1): sending packet to 172.16.172.53 (I) QM_IDLE ISAKMP (0:1): purging node 1272270610 ISAKMP (0:1): incrementing error counter on sa: PEERS_ALIVE_TIMER ISAKMP (0:1): peer not responding! ISAKMP (0:1): peer does paranoid keepalives. ISAKMP (0:1): phase 1 going away; let's be paranoid. ISAKMP (0:1): Bring down phase 2's ISAKMP (0:1): That phase 1 was the last one of its kind. Taking phase 2's with us. ISAKMP (0:1): peer does paranoid keepalives. ISAKMP (0:1): deleting SA reason "P1 errcounter exceeded (PEERS_ALIVE_TIMER)" state (I) QM_IDLE (peer 172.16.172.53) input queue 0 IPSEC(key_engine): got a queue event... IPSEC(key_engine_delete_sas): rec'd delete notify from ISAKMP IPSEC(key_engine_delete_sas): delete all SAs shared with 172.16.172.53 IPSEC(delete_sa): deleting SA, (sa) sa_dest= 172.16.172.69, sa_prot= 50, sa_spi= 0x44E0B22B(1155576363), sa_trans= esp-des esp-md5-hmac , sa_conn_id= 2029 IPSEC(delete_sa): deleting SA, (sa) sa_dest= 172.16.172.53, sa_prot= 50, sa_spi= 0x5B23F22E(1529082414), sa_trans= esp-des esp-md5-hmac , sa_conn_id= 2030 ISAKMP (0:1): sending packet to 172.16.172.53 (I) MM_NO_STATE ISAKMP (0:1): purging node -248155233 ISAKMP (0:1): peer does paranoid keepalives. IPSEC(key_engine): got a queue event... IPSEC(key_engine_delete_sas): rec'd delete notify from ISAKMP IPSEC(key_engine_delete_sas): delete all SAs shared with 172.16.172.53 ISAKMP (0:1): purging node 958118275
Quando si verifica il failover sul router HSRP primario Cisco 7204VXR-1, il dispositivo diventa un router di standby. Le associazioni di protezione ISAKMP e IPSec esistenti vengono eliminate. Il router HSRP secondario Cisco 7204VXR-2 diventa attivo e stabilisce nuove SA IPSec con Cisco VPN 7200.
L'output del comando debug standby events visualizza gli eventi correlati a HSRP.
HSRP: Fa0/0 API Software interface going down HSRP: Fa0/0 API Software interface going down HSRP: Fa0/0 Interface down HSRP: Fa0/0 Grp 1 Active: b/HSRP disabled HSRP: Fa0/0 Grp 1 Active router is unknown, was local HSRP: Fa0/0 Grp 1 Standby router is unknown, was 172.16.172.54 HSRP: Fa0/0 Grp 1 Active -> Init %HSRP-6-STATECHANGE: FastEthernet0/0 Grp 1 state Active -> Init HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Active -> Init %CRYPTO-5-SESSION_STATUS: Crypto tunnel is DOWN. Peer 172.16.172.69:500 Id: 172.16.172.69 HSRP: Fa0/0 Grp 1 Redundancy enquiry for VPNHA succeeded HSRP: Fa0/0 API Add active HSRP addresses to ARP table %LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down HSRP: API Hardware state change %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down
Poiché l'interfaccia è chiusa, lo stato dell'HSRP cambia in "Init".
paal#show standby FastEthernet0/0 - Group 1 State is Init (interface down) 3 state changes, last state change 00:07:29 Virtual IP address is 172.16.172.53 Active virtual MAC address is unknown Local virtual MAC address is 0000.0c07.ac01 (v1 default) Hello time 3 sec, hold time 10 sec Preemption enabled Active router is unknown Standby router is unknown Priority 200 (configured 200) Track interface FastEthernet0/1 state Up decrement 150 IP redundancy name is "VPNHA" (cfgd)
Cisco 7204VXR-2 diventa il router HSRP attivo e cambia il suo stato in "Attivo".
HSRP: Fa0/0 Grp 1 Standby: c/Active timer expired (172.16.172.52) HSRP: Fa0/0 Grp 1 Active router is local, was 172.16.172.52 HSRP: Fa0/0 Grp 1 Standby router is unknown, was local HSRP: Fa0/0 Grp 1 Standby -> Active (active 0->1, passive 2->1) %HSRP-6-STATECHANGE: FastEthernet0/0 Grp 1 state Standby -> Active HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Standby -> Active !--- VPN route 20.1.1.0/24 is added to the routing table. IPSEC(rte_mgr): VPN Route Added 20.1.1.0 255.255.255.0 via 172.16.172.69 in IP DEFAULT TABLE 7204VXR-2#show standby FastEthernet0/0 - Group 1 State is Active 2 state changes, last state change 00:10:38 Virtual IP address is 172.16.172.53 Active virtual MAC address is 0000.0c07.ac01 Local virtual MAC address is 0000.0c07.ac01 (v1 default) Hello time 3 sec, hold time 10 sec Next hello sent in 0.116 secs Preemption enabled Active router is local Standby router is unknown Priority 100 (default 100) Track interface FastEthernet1/0 state Up decrement 10 IP redundancy name is "VPNHA" (cfgd)
Se RRI è abilitato, le route VPN vengono aggiornate dinamicamente durante il failover. Il router statico 20.1.1.0/24 viene rimosso e il router Cisco 7204VXR-1 apprende il percorso dal router Cisco 7204VXR-2.
L'output del comando show ip route mostra questo aggiornamento dinamico.
7204VXR-1#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 not set
99.0.0.0/32 is subnetted, 1 subnets
O 99.99.99.99 [110/2] via 10.1.1.3, 02:46:16, FastEthernet0/1
20.0.0.0/24 is subnetted, 1 subnets
O E2 20.1.1.0 [110/20] via 10.1.1.2, 00:08:35, FastEthernet0/1
172.16.0.0/28 is subnetted, 1 subnets
O E2 172.16.172.64 [110/20] via 10.1.1.2, 00:07:56, FastEthernet0/1
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/24 is directly connected, FastEthernet0/1
S 10.48.66.0/23 [1/0] via 10.1.1.2
Il percorso VPN statico viene iniettato nella tabella di routing sul router Cisco 7204VXR-2.
7204VXR-2#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 not set
99.0.0.0/32 is subnetted, 1 subnets
O 99.99.99.99 [110/2] via 10.1.1.3, 03:04:18, FastEthernet1/0
20.0.0.0/24 is subnetted, 1 subnets
S 20.1.1.0 [1/0] via 172.16.172.69
172.16.0.0/28 is subnetted, 2 subnets
C 172.16.172.48 is directly connected, FastEthernet0/0
S 172.16.172.64 [1/0] via 172.16.172.49
10.0.0.0/24 is subnetted, 1 subnets
C 10.1.1.0 is directly connected, FastEthernet1/0
Il router interno 7206-1 apprende la route 20.1.1/24 al peer VPN remoto dal router adiacente OSPF 7204VXR-2. Queste modifiche di routing si verificano in modo dinamico tramite la combinazione di HSRP/RRI e OSPF.
7206-1#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 not set
99.0.0.0/32 is subnetted, 1 subnets
C 99.99.99.99 is directly connected, Loopback0
20.0.0.0/24 is subnetted, 1 subnets
O E2 20.1.1.0 [110/20] via 10.1.1.2, 00:13:55, FastEthernet0/1
172.16.0.0/28 is subnetted, 1 subnets
O E2 172.16.172.64 [110/20] via 10.1.1.2, 00:13:17, FastEthernet0/1
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/24 is directly connected, FastEthernet0/1
O E2 10.48.66.0/23 [110/20] via 10.1.1.2, 03:06:08, FastEthernet0/1
Dopo che Cisco 7204VXR-2 diventa il router attivo durante il failover HSRP, il traffico VPN tra Cisco 7204VXR-2 e Cisco VPN 7200 richiama le associazioni di protezione ISAKMP e IPSec.
Di seguito viene riportato l'output dei comandi show crypto isakmp sa e show crypto ipsec sa sul router VPN 7200:
7204VXR-2#show crypto isakmp sa detail
Codes: C - IKE configuration mode, D - Dead Peer Detection
K - Keepalives, N - NAT-traversal
X - IKE Extended Authentication
psk - Preshared key, rsig - RSA signature
renc - RSA encryption
C-id Local Remote I-VRF Encr Hash Auth DH Lifetime Cap.
1 172.16.172.53 172.16.172.69 des md5 psk 1 23:53:47 K
Connection-id:Engine-id = 1:1(software)
7204VXR-2#show crypto ipsec sa
interface: FastEthernet0/0
Crypto map tag: vpn, local addr. 172.16.172.53
protected vrf:
local ident (addr/mask/prot/port): (99.99.99.99/255.255.255.255/0/0)
remote ident (addr/mask/prot/port): (20.1.1.0/255.255.255.0/0/0)
current_peer: 172.16.172.69:500
PERMIT, flags={origin_is_acl,}
#pkts encaps: 9, #pkts encrypt: 9, #pkts digest: 9
#pkts decaps: 9, #pkts decrypt: 9, #pkts verify: 9
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0
#pkts not decompressed: 0, #pkts decompress failed: 0
#send errors 0, #recv errors 0
local crypto endpt.: 172.16.172.53, remote crypto endpt.: 172.16.172.69
path mtu 1500, media mtu 1500
current outbound spi: 83827275
inbound esp sas:
spi: 0x8D70E8A3(2372987043)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2000, flow_id: 1, crypto map: vpn
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4453897/3162)
ike_cookies: 95074F89 3FF73F2B F70FEDF6 5998090C
IV size: 8 bytes
replay detection support: Y
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x83827275(2206364277)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2001, flow_id: 2, crypto map: vpn
crypto engine type: Software, engine_id: 1
sa timing: remaining key lifetime (k/sec): (4453898/3162)
ike_cookies: 95074F89 3FF73F2B F70FEDF6 5998090C
IV size: 8 bytes
replay detection support: Y
outbound ah sas:
outbound pcp sas: vpn7200#show crypto isa sa
dst src state conn-id slot
172.16.172.53 172.16.172.69 QM_IDLE 1 0
vpn7200#show crypto ipsec sa
interface: FastEthernet0/1
Crypto map tag: vpn, local addr. 172.16.172.69
local ident (addr/mask/prot/port): (20.1.1.0/255.255.255.0/0/0)
remote ident (addr/mask/prot/port): (99.99.99.99/255.255.255.255/0/0)
current_peer: 172.16.172.53
PERMIT, flags={origin_is_acl,}
#pkts encaps: 19, #pkts encrypt: 19, #pkts digest 19
#pkts decaps: 19, #pkts decrypt: 19, #pkts verify 19
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0
#send errors 6, #recv errors 0
local crypto endpt.: 172.16.172.69, remote crypto endpt.: 172.16.172.53
path mtu 1500, ip mtu 1500
current outbound spi: 8D70E8A3
inbound esp sas:
spi: 0x83827275(2206364277)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2029, flow_id: 1, crypto map: vpn
sa timing: remaining key lifetime (k/sec): (4607997/3070)
IV size: 8 bytes
replay detection support: Y
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x8D70E8A3(2372987043)
transform: esp-des esp-md5-hmac ,
in use settings ={Tunnel, }
slot: 0, conn id: 2030, flow_id: 2, crypto map: vpn
sa timing: remaining key lifetime (k/sec): (4607998/3070)
IV size: 8 bytes
replay detection support: Y
outbound ah sas:
outbound pcp sas:
Dopo il ripristino del router primario originale HSRP da un'interruzione
Dopo il ripristino del servizio sul router primario originale HSRP Cisco 7204VXR-1, il dispositivo riprende la posizione di router attivo perché ha una priorità più alta e perché è configurata la priorità HSRP.
L'output dei comandi show e debug restituito da diversi router mostra un altro passaggio di HSRP e IPSec. Le associazioni di protezione ISAKMP e IPSec vengono ristabilite automaticamente e le informazioni di routing vengono aggiornate in modo dinamico.
In questo output di esempio viene mostrato che lo stato del router 7204VXR-1 viene modificato in "Attivo".
HSRP: Fa0/0 API 172.16.172.52 is not an HSRP address HSRP: Fa0/0 API MAC address update HSRP: Fa0/0 API Software interface coming up %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up HSRP: API Hardware state change HSRP: Fa0/0 API Software interface coming up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up HSRP: Fa0/0 Interface up HSRP: Fa0/0 Starting minimum interface delay (1 secs) HSRP: Fa0/0 Interface min delay expired HSRP: Fa0/0 Grp 1 Init: a/HSRP enabled HSRP: Fa0/0 Grp 1 Init -> Listen HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Init -> Backup HSRP: Fa0/0 Grp 1 Listen: c/Active timer expired (unknown) HSRP: Fa0/0 Grp 1 Listen -> Speak HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Backup -> Speak HSRP: Fa0/0 Grp 1 Speak: d/Standby timer expired (unknown) HSRP: Fa0/0 Grp 1 Standby router is local HSRP: Fa0/0 Grp 1 Speak -> Standby HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Speak -> Standby HSRP: Fa0/0 Grp 1 Redundancy enquiry for VPNHA succeeded HSRP: Fa0/0 Grp 1 Standby: c/Active timer expired (unknown) HSRP: Fa0/0 Grp 1 Active router is local HSRP: Fa0/0 Grp 1 Standby router is unknown, was local HSRP: Fa0/0 Grp 1 Standby -> Active %HSRP-6-STATECHANGE: FastEthernet0/0 Grp 1 state Standby -> Active HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Standby -> Active HSRP: Fa0/0 Grp 1 Active: i/Resign rcvd (100/172.16.172.54) HSRP: Fa0/0 Grp 1 Redundancy group VPNHA state Active -> Active HSRP: Fa0/0 Grp 1 Redundancy group VPNHA state Active -> Active HSRP: Fa0/0 Grp 1 Standby router is 172.16.172.54
Lo stato del router 7204VXR-2 viene modificato in "Standby". La route VPN viene rimossa dalla tabella di routing.
HSRP: Fa0/0 Grp 1 Standby router is 172.16.172.52 HSRP: Fa0/0 Grp 1 Hello in 172.16.172.52 Active pri 200 vIP 172.16.172.53 hel 3000 hol 10000 id 0000.0c07.ac01 HSRP: Fa0/0 Grp 1 Active router is 172.16.172.52, was local HSRP: Fa0/0 Grp 1 Standby router is unknown, was 172.16.172.52 HSRP: Fa0/0 Grp 1 Active: g/Hello rcvd from higher pri Active router (200/172.16.172.52) HSRP: Fa0/0 Grp 1 Active -> Speak (active 1->0, passive 0->1) %HSRP-6-STATECHANGE: FastEthernet0/0 Grp 1 state Active -> Speak HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Active -> Speak HSRP: Fa0/0 Grp 1 Speak: d/Standby timer expired (unknown) HSRP: Fa0/0 Grp 1 Standby router is local HSRP: Fa0/0 Grp 1 Speak -> Standby (active 0, passive 1) HSRP: Fa0/0 Grp 1 Redundancy "VPNHA" state Speak -> Standby HSRP: Fa0/0 Grp 1 Redundancy enquiry for VPNHA succeeded addr 172.16.172.53 name VPNHA state Speak active 172.16.172.52 standby 172.16.172.54 !--- The VPN route is removed. IPSEC(rte_mgr): VPN Route Removed 20.1.1.0 255.255.255.0 via 172.16.172.69 in IP DEFAULT TABLE
Informazioni correlate
Cronologia delle revisioni
| Revisione | Data di pubblicazione | Commenti |
|---|---|---|
1.0 |
08-Sep-2004 |
Versione iniziale |
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