This sample configuration illustrates a router configured for mode configuration (user gets an IP address from the pool), wild-card pre-shared keys (all PC clients share a common key), and network address translation (NAT). In this configuration, an off-site user can enter the network and have an internal IP address assigned from the pool. To users, it appears that they are inside the network. Because private addressing, hence NAT, is involved, the router must be told what to translate and what not to translate.
There are no specific requirements for this document.
The information in this document is based on these software and hardware versions:
Cisco IOS® Software Release 12.0.7T or later
Hardware that supports this software revision
CiscoSecure VPN Client 1.0/10A or 1.1 (shown as 2.0.7/E or 2.1.12, respectively, go to Help > About to check)
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
For more information on document conventions, refer to the Cisco Technical Tips Conventions .
In this section, you are presented with the information to configure the features described in this document.
Note: To find additional information on the commands used in this document, use the Command Lookup Tool (registered customers only) .
This document uses the network setup shown in this diagram.
This document uses these configurations.
VPN Client Configuration |
---|
Network Security policy: 1- Myconn My Identity = ip address Connection security: Secure Remote Party Identity and addressing ID Type: IP subnet 10.2.2.0 Port all Protocol all Connect using secure tunnel ID Type: IP address 201.70.32.101 Authentication (Phase 1) Proposal 1 Authentication method: pre-shared key Encryp Alg: DES Hash Alg: MD5 SA life: Unspecified Key Group: DH 1 Key exchange (Phase 2) Proposal 1 Encapsulation ESP Encrypt Alg: DES Hash Alg: MD5 Encap: tunnel SA life: Unspecified no AH 2- Other Connections Connection security: Non-secure Local Network Interface Name: Any IP Addr: Any Port: All |
Router Configuration |
---|
Current configuration: ! version 12.0 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname Router ! enable secret 5 $1$v5OP$mPuiEQn8ULa8hVMYVOV1D. enable password ww ! ip subnet-zero ! cns event-service server ! !--- IKE configuration. crypto isakmp policy 1 hash md5 authentication pre-share crypto isakmp key cisco123 address 0.0.0.0 crypto isakmp client configuration address-pool local ourpool ! !--- IPSec configuration. crypto ipsec transform-set trans1 esp-des esp-md5-hmac ! crypto dynamic-map dynmap 10 set transform-set trans1 ! crypto map intmap client configuration address initiate crypto map intmap client configuration address respond crypto map intmap 10 ipsec-isakmp dynamic dynmap ! interface Ethernet0 ip address 201.70.32.101 255.255.255.0 no ip directed-broadcast ip nat outside no ip route-cache no ip mroute-cache crypto map intmap ! interface Serial1 ip address 10.2.2.1 255.255.255.0 no ip directed-broadcast ip nat inside ! ip local pool ourpool 10.2.1.1 10.2.1.254 ip nat pool outsidepool 201.70.32.150 201.70.32.160 netmask 255.255.255.0 !--- Except the private network to private network traffic !--- from the NAT process. ip nat inside source route-map nonat pool outsidepool ip classless ip route 0.0.0.0 0.0.0.0 201.70.32.1 no ip http server !--- Except the private network to private network traffic !--- from the NAT process. access-list 101 deny ip 10.2.2.0 0.0.0.255 10.2.1.0 0.0.0.255 access-list 101 permit ip 10.2.2.0 0.0.0.255 any route-map nonat permit 10 match ip address 101 ! line con 0 transport input none line aux 0 line vty 0 4 password ww login ! end |
This section provides information you can use to confirm your configuration is working properly.
Certain show commands are supported by the Output Interpreter Tool (registered customers only) , which allows you to view an analysis of show command output.
show crypto engine connections active—Shows the encrypted and decrypted packets.
show crypto ipsec sa—Shows the phase 2 security associations.
show crypto isakmp sa—Shows the phase 1 security associations.
This section provides information you can use to troubleshoot your configuration.
Note: Before issuing debug commands, refer to Important Information on Debug Commands.
These debugs must run on both IPSec routers (peers). Clearing security associations must be done on both peers.
debug crypto ipsec—Displays the IPSec negotiations of phase 2.
debug crypto isakmp—Displays the ISAKMP negotiations of phase 1.
debug crypto engine—Displays the traffic that is encrypted.
clear crypto isakmp—Clears the security associations related to phase 1.
clear crypto sa—Clears the security associations related to phase 2.
Router Debugs |
---|
Apr 18 15:17:59: ISAKMP (4): received packet from 201.70.32.82 (R) MM_NO_STATE Apr 18 15:17:59: ISAKMP (4): received packet from 201.70.32.82 (R) MM_NO_STATE Apr 18 15:18:03: ISAKMP (0): received packet from 201.70.32.82 (N) NEW SA Apr 18 15:18:03: ISAKMP (0:5): processing SA payload. message ID = 0 Apr 18 15:18:03: ISAKMP (0:5): Checking ISAKMP transform 1 against priority 1 policy Apr 18 15:18:03: ISAKMP: encryption DES-CBC Apr 18 15:18:03: ISAKMP: hash MD5 Apr 18 15:18:03: ISAKMP: default group 1 Apr 18 15:18:03: ISAKMP: auth pre-share Apr 18 15:18:03: ISAKMP (0:5): atts are acceptable. Next payload is 0 Apr 18 15:18:03: CryptoEngine0: generate alg parameter Apr 18 15:18:05: CRYPTO_ENGINE: Dh phase 1 status: 0 Apr 18 15:18:05: CRYPTO_ENGINE: Dh phase 1 status: 0 Apr 18 15:18:05: ISAKMP (0:5): SA is doing pre-shared key authentication Apr 18 15:18:05: ISAKMP (5): SA is doing pre-shared key authentication using id type ID_IPV4_ADDR Apr 18 15:18:05: ISAKMP (5): sending packet to 201.70.32.82 (R) MM_SA_SETUP Apr 18 15:18:05: ISAKMP (5): received packet from 201.70.32.82 (R) MM_SA_SETUP Apr 18 15:18:05: ISAKMP (0:5): processing KE payload. message ID = 0 Apr 18 15:18:05: CryptoEngine0: generate alg parameter Apr 18 15:18:05: CRYPTO_ENGINE: Dh phase 1 status: 0 Apr 18 15:18:05: CRYPTO_ENGINE: Dh phase 1 status: 0 Apr 18 15:18:05: ISAKMP (0:5): SA is doing pre-shared key authentication Apr 18 15:18:05: ISAKMP (5): SA is doing pre-shared key authentication using id type ID_IPV4_ADDR Apr 18 15:18:05: ISAKMP (5): sending packet to 201.70.32.82 (R) MM_SA_SETUP Apr 18 15:18:05: ISAKMP (5): received packet from 201.70.32.82 (R) MM_SA_SETUP Apr 18 15:18:05: ISAKMP (0:5): processing KE payload. message ID = 0 Apr 18 15:18:05: CryptoEngine0: generate alg parameter Apr 18 15:18:07: ISAKMP (0:5): processing NONCE payload. message ID = 0 Apr 18 15:18:07: CryptoEngine0: create ISAKMP SKEYID for conn id 5 Apr 18 15:18:07: ISAKMP (0:5): SKEYID state generated Apr 18 15:18:07: ISAKMP (0:5): processing vendor id payload Apr 18 15:18:07: ISAKMP (0:5): processing vendor id payload Apr 18 15:18:07: ISAKMP (5): sending packet to 201.70.32.82 (R) MM_KEY_EXCH Apr 18 15:18:07: ISAKMP (0:4): purging SA. Apr 18 15:18:07: ISAKMP (0:4): purging node -1412157317 Apr 18 15:18:07: ISAKMP (0:4): purging node 1875403554 Apr 18 15:18:07: CryptoEngine0: delete connection 4 Apr 18 15:18:08: ISAKMP (5): received packet from 201.70.32.82 (R) MM_KEY_EXCH Apr 18 15:18:08: ISAKMP (0:5): processing ID payload. message ID = 0 Apr 18 15:18:08: ISAKMP (0:5): processing HASH payload. message ID = 0 Apr 18 15:18:08: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:08: ISAKMP (5): processing NOTIFY payload 24578 protocol 1 spi 0, message ID = 0 Apr 18 15:18:08: ISAKMP (0:5): SA has been authenticated with 201.70.32.82 Apr 18 15:18:08: ISAKMP (5): ID payload next-payload : 8 type : 1 protocol : 17 port : 500 length : 8 Apr 18 15:18:08: ISAKMP (5): Total payload length: 12 Apr 18 15:18:08: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:08: CryptoEngine0: clear dh number for conn id 1 Apr 18 15:18:08: ISAKMP (5): sending packet to 201.70.32.82 (R) QM_IDLE Apr 18 15:18:08: ISAKMP (5): received packet from 201.70.32.82 (R) QM_IDLE Apr 18 15:18:08: ISAKMP (0:5): Locking struct 14D0DC on allocation Apr 18 15:18:08: ISAKMP (0:5): allocating address 10.2.1.1 Apr 18 15:18:08: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:08: ISAKMP (0:5): initiating peer config to 201.70.32.82. message ID = 1226793520 Apr 18 15:18:08: ISAKMP (5): sending packet to 201.70.32.82 (R) QM_IDLE Apr 18 15:18:09: ISAKMP (5): received packet from 201.70.32.82 (R) QM_IDLE Apr 18 15:18:09: ISAKMP (0:5): processing transaction payload from 201.70.32.82. message ID = 1226793520 Apr 18 15:18:09: ISAKMP: recieved config from 201.70.32.82 . Apr 18 15:18:09: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:09: ISAKMP: Config payload type: 4 Apr 18 15:18:09: ISAKMP (0:5): peer accepted the address! Apr 18 15:18:09: ISAKMP (0:5): adding static route for 10.2.1.1 Apr 18 15:18:09: ISAKMP (0:5): deleting node 1226793520 Apr 18 15:18:09: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:09: ISAKMP (0:5): processing SA payload. message ID = -617682048 Apr 18 15:18:09: ISAKMP (0:5): Checking IPSec proposal 1 Apr 18 15:18:09: ISAKMP: transform 1, ESP_DES Apr 18 15:18:09: ISAKMP: attributes in transform: Apr 18 15:18:09: ISAKMP: authenticator is HMAC-MD5 Apr 18 15:18:09: ISAKMP: encaps is 1 Apr 18 15:18:09: validate proposal 0 Apr 18 15:18:09: ISAKMP (0:5): atts are acceptable. Apr 18 15:18:09: IPSEC(validate_proposal_request): proposal part #1, (key eng. msg.) dest= 201.70.32.101, src= 201.70.32.82, dest_proxy= 10.2.2.0/255.255.255.0/0/0 (type=4), src_proxy= 10.2.1.1/255.255.255.255/0/0 (type=1), protocol= ESP, transform= esp-des esp-md5-hmac , lifedur= 0s and 0kb, spi= 0x0(0), conn_id= 0, keysize= 0, flags= 0x4 Apr 18 15:18:09: validate proposal request 0 Apr 18 15:18:09: ISAKMP (0:5): processing NONCE payload. message ID = -617682048 Apr 18 15:18:09: ISAKMP (0:5): processing ID payload. message ID = -617682048 Apr 18 15:18:09: ISAKMP (5): ID_IPV4_ADDR src 10.2.1.1 prot 0 port 0 Apr 18 15:18:09: ISAKMP (0:5): processing ID payload. message ID = -617682048 Apr 18 15:18:09: ISAKMP (5): ID_IPV4_ADDR_SUBNET dst 10.2.2.0/255.255.255.0 prot 0 port 0 Apr 18 15:18:09: IPSEC(key_engine): got a queue event... Apr 18 15:18:09: IPSEC(spi_response): getting spi 153684796 for SA from 201.70.32.82 to 201.70.32.101 for prot 3 Apr 18 15:18:09: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:09: ISAKMP (5): sending packet to 201.70.32.82 (R) QM_IDLE Apr 18 15:18:09: ISAKMP (5): received packet from 201.70.32.82 (R) QM_IDLE Apr 18 15:18:09: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:09: ISAKMP (0:5): processing SA payload. message ID = -1078114754 Apr 18 15:18:09: ISAKMP (0:5): Checking IPSec proposal 1 Apr 18 15:18:10: ISAKMP: transform 1, ESP_DES Apr 18 15:18:10: ISAKMP: attributes in transform: Apr 18 15:18:10: ISAKMP: authenticator is HMAC-MD5 Apr 18 15:18:10: ISAKMP: encaps is 1 Apr 18 15:18:10: validate proposal 0 Apr 18 15:18:10: ISAKMP (0:5): atts are acceptable. Apr 18 15:18:10: IPSEC(validate_proposal_request): proposal part #1, (key eng. msg.) dest= 201.70.32.101, src= 201.70.32.82, dest_proxy= 10.2.2.0/255.255.255.0/0/0 (type=4), src_proxy= 10.2.1.1/255.255.255.255/0/0 (type=1), protocol= ESP, transform= esp-des esp-md5-hmac , lifedur= 0s and 0kb, spi= 0x0(0), conn_id= 0, keysize= 0, flags= 0x4 Apr 18 15:18:10: validate proposal request 0 Apr 18 15:18:10: ISAKMP (0:5): processing NONCE payload. message ID = -1078114754 Apr 18 15:18:10: ISAKMP (0:5): processing ID payload. message ID = -1078114754 Apr 18 15:18:10: ISAKMP (5): ID_IPV4_ADDR src 10.2.1.1 prot 0 port 0 Apr 18 15:18:10: ISAKMP (0:5): processing ID payload. message ID = -1078114754 Apr 18 15:18:10: ISAKMP (5): ID_IPV4_ADDR_SUBNET dst 10.2.2.0/255.255.255.0 prot 0 port 0 Apr 18 15:18:10: IPSEC(key_engine): got a queue event... Apr 18 15:18:10: IPSEC(spi_response): getting spi 224008976 for SA from 201.70.32.82 to 201.70.32.101 for prot 3 Apr 18 15:18:10: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:10: ISAKMP (5): sending packet to 201.70.32.82 (R) QM_IDLE Apr 18 15:18:10: ISAKMP (5): received packet from 201.70.32.82 (R) QM_IDLE Apr 18 15:18:10: CryptoEngine0: generate hmac context for conn id 5 Apr 18 15:18:10: ipsec allocate flow 0 Apr 18 15:18:10: ipsec allocate flow 0 Apr 18 15:18:10: ISAKMP (0:5): Creating IPSec SAs Apr 18 15:18:10: inbound SA from 201.70.32.82 to 201.70.32.101 (proxy 10.2.1.1 to 10.2.2.0) Apr 18 15:18:10: has spi 224008976 and conn_id 2000 and flags 4 Apr 18 15:18:10: outbound SA from 201.70.32.101 to 201.70.32.82 (proxy 10.2.2.0 to 10.2.1.1) Apr 18 15:18:10: has spi -1084694986 and conn_id 2001 and flags 4 Apr 18 15:18:10: ISAKMP (0:5): deleting node -1078114754 Apr 18 15:18:10: IPSEC(key_engine): got a queue event... Apr 18 15:18:10: IPSEC(initialize_sas): , (key eng. msg.) dest= 201.70.32.101, src= 201.70.32.82, dest_proxy= 10.2.2.0/255.255.255.0/0/0 (type=4), src_proxy= 10.2.1.1/0.0.0.0/0/0 (type=1), protocol= ESP, transform= esp-des esp-md5-hmac , lifedur= 0s and 0kb, spi= 0xD5A1B10(224008976), conn_id= 2000, keysize= 0, flags= 0x4 Apr 18 15:18:10: IPSEC(initialize_sas): , (key eng. msg.) src= 201.70.32.101, dest= 201.70.32.82, src_proxy= 10.2.2.0/255.255.255.0/0/0 (type=4), dest_proxy= 10.2.1.1/0.0.0.0/0/0 (type=1), protocol= ESP, transform= esp-des esp-md5-hmac , lifedur= 0s and 0kb, spi= 0xBF58DE36(3210272310), conn_id= 2001, keysize= 0, flags= 0x4 Apr 18 15:18:10: IPSEC(create_sa): sa created, (sa) sa_dest= 201.70.32.101, sa_prot= 50, sa_spi= 0xD5A1B10(224008976), sa_trans= esp-des esp-md5-hmac , sa_conn_id= 2000 Apr 18 15:18:10: IPSEC(create_sa): sa created, (sa) sa_dest= 201.70.32.82, sa_prot= 50, sa_spi= 0xBF58DE36(3210272310), sa_trans= esp-des esp-md5-hmac , sa_conn_id= 2001 Apr 18 15:18:10: ISAKMP: Locking struct 14D0DC for IPSEC Apr 18 15:18:24: ISAKMP (0:5): retransmitting phase 2 -617682048 ... Apr 18 15:18:24: ISAKMP (5): sending packet to 201.70.32.82 (R) QM_IDLE Router#show crypto ipsec Apr 18 15:18:39: ISAKMP (0:5): retransmitting phase 2 -617682048 ... Apr 18 15:18:39: ISAKMP (5): sending packet to 201.70.32.82 (R) QM_IDLE sa interface: Ethernet0 Crypto map tag: intmap, local addr. 201.70.32.101 local ident (addr/mask/prot/port): (10.2.2.0/255.255.255.0/0/0) remote ident (addr/mask/prot/port): (10.2.1.1/255.255.255.255/0/0) current_peer: 201.70.32.82 PERMIT, flags={} #pkts encaps: 7, #pkts encrypt: 7, #pkts digest 7 #pkts decaps: 7, #pkts decrypt: 7, #pkts verify 7 #pkts compressed: 0, #pkts decompressed: 0 #pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0 #send errors 0, #recv errors 0 local crypto endpt.: 201.70.32.101, remote crypto endpt.: 201.70.32.82 path mtu 1500, media mtu 1500 current outbound spi: BF58DE36 inbound esp sas: spi: 0xD5A1B10(224008976) transform: esp-des esp-md5-hmac , in use settings ={Tunnel, } slot: 0, conn id: 2000, flow_id: 1, crypto map: intmap sa timing: remaining key lifetime (k/sec): (4607999/3500) IV size: 8 bytes replay detection support: Y inbound ah sas: inbound pcp sas: outbound esp sas: spi: 0xBF58DE36(3210272310) transform: esp-des esp-md5-hmac , in use settings ={Tunnel, } slot: 0, conn id: 2001, flow_id: 2, crypto map: intmap sa timing: remaining key lifetime (k/sec): (4607999/3500) IV size: 8 bytes replay detection support: Y outbound ah sas: outbound pcp sas: Router#sho crypto engine connections active ID Interface IP-Address State Algorithm Encrypt Decrypt 5 set HMAC_MD5+DES_56_CB 0 0 2000 Ethernet0 201.70.32.101 set HMAC_MD5+DES_56_CB 0 7 2001 Ethernet0 201.70.32.101 set HMAC_MD5+DES_56_CB 7 0 Crypto adjacency count : Lock: 0, Unlock: 0 |
VPN Client Information |
---|
Client configuration: C:\>ping -t 10.2.2.5 Reply from 10.2.2.5: bytes=32 time<0ms TTL=352 Reply from 10.2.2.5: bytes=32 time<10ms TTL=352 From Logview: 14:25:34.044 New Connection - Initiating IKE Phase 1 (IP ADDR=201.70.32.101) 14:25:34.144 New Connection - SENDING>>>> ISAKMP OAK MM (SA) 14:25:35.886 New Connection - RECEIVED<<< ISAKMP OAK MM (SA) 14:25:36.067 New Connection - SENDING>>>> ISAKMP OAK MM (KE, NON, VID, VID) 14:25:38.310 New Connection - RECEIVED<<< ISAKMP OAK MM (KE, NON, VID) 14:25:38.460 New Connection - SENDING>>>> ISAKMP OAK MM *(ID, HASH, NOTIFY:STATUS_INITIAL_CONTACT) 14:25:38.610 New Connection - RECEIVED<<< ISAKMP OAK MM *(ID, HASH) 14:25:38.710 New Connection - Established IKE SA 14:25:38.811 New Connection - Initiating IKE Phase 2 with Client IDs (message id : B01876) 14:25:38.911 Initiator = IP ADDR=201.70.32.82, prot = 0 port = 0 14:25:39.011 Responder = IP SUBNET/MASK=10.2.2.0/255.255.255.0, prot = 0 port = 0 14:25:39.111 New Connection - SENDING>>>> ISAKMP OAK QM *(HASH, SA, NON, ID, ID) 14:25:39.251 New Connection - RECEIVED<<< ISAKMP OAK TRANS *(HASH, ATTR) 14:25:39.351 New Connection - Received Private IP Address = IP ADDR=10.2.1.1 14:25:39.451 New Connection - Discarding IPSec SA negotiation (message id: B01876) 14:25:39.552 New Connection - SENDING>>>> ISAKMP OAK TRANS *(HASH, ATTR) 14:25:40.022 New Connection - Received message for discarded IPSec SA negotiation (message id: B01876) 14:25:40.122 New Connection - Initiating IKE Phase 2 with Client IDs (message id: C8CB0CE) 14:25:40.223 Initiator = IP ADDR=10.2.1.1, prot = 0 port = 0 14:25:40.323 Responder = IP SUBNET/MASK=10.2.2.0/255.255.255.0, prot = 0 port = 0 14:25:40.423 New Connection - SENDING>>>> ISAKMP OAK QM *(HASH, SA, NON, ID, ID) 14:25:40.873 New Connection - RECEIVED<<< ISAKMP OAK QM *(HASH, SA, NON, ID, ID, NOTIFY:STATUS_RESP_LIFETIME) 14:25:40.974 New Connection - SENDING>>>> ISAKMP OAK QM *(HASH) 14:25:41.074 New Connection - Loading IPSec SA (Message ID = C8CB0CE OUTBOUND SPI = 19A22423 INBOUND SPI = E4829433) 14:25:41.174 |
Revision | Publish Date | Comments |
---|---|---|
1.0 |
11-Dec-2001 |
Initial Release |