VPN tunnels are used to connect physically isolated networks that are more often than not separated by nonsecure internetworks. To protect these connections, we employ the IP Security (IPSec) protocol to make secure the transmission of data, voice, and video between sites. These secure tunnels over the Internet public network are encrypted using a number of advanced algorithms to provide confidentiality of data that is transmitted between multiple sites. This chapter explores how to configure routers to create a permanent secure site-to-site VPN tunnel.
Encryption will be provided by IPSec in concert with VPN tunnels. The Internet Security Association and Key Management Protocol (ISAKMP) and IPSec are essential to building and encrypting VPN tunnels. ISAKMP, also called IKE (Internet Key Exchange), is the negotiation protocol that allows hosts to agree on how to build an IPSec security association.
ISAKMP negotiation consists of two phases:
Phase 1 creates the first tunnel, which protects later ISAKMP negotiation messages.
Phase 2 creates the tunnel that protects data.
IPSec then encrypts exchanged data by employing encryption algorithms that result in authentication, encryption, and critical anti-replay services.
Lab 13-1: Basic Site-to-Site IPSec VPN
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Figure 13-1 Configuring Basic Site-to-Site IPSec VPN (Main Mode)
Figure 13-1 illustrates the topology that will be used in the following lab.
Task 1
Configure a basic site-to-site IPSec VPN to protect traffic between IP addresses 1.1.1.1 and 2.2.2.2 using the policy shown in Table 13-1.
Table 13-1 Policy Guidelines for Configuring Task 1
| ISAKMP Policy | IPSec Policy |
| Authentication: Pre-shared | Encryption: ESP-3DES |
| Hash: MD5 | Hash: ESP-MD5-HMAC |
| DH Group: 2 | Proxy-ID/Crypto ACL: 1.1.1.1 ←→ 2.2.2.2 |
| Encryption: 3DES | |
| PSK: cisco |
Reachability to the loopback0 interfaces is provided in the initial configuration.
ISAKMP, originally defined in RFC 7296, covers the following:
Procedures to authenticate a communicating peer
How to create and manage security associations (SAs)
Key-generation techniques
Threat mitigation, such as denial-of-service (DoS) and replay attacks
IKE does not specify any details of key management or key exchange, and it’s not bound to any key-generation techniques. Inside IKE, Cisco uses OAKLEY for the key exchange protocol.
OAKLEY enables you to choose between different well-known Diffie-Hellman (DH) groups. RFC 2412 describes the OAKLEY protocol and covers DH groups 1 through 5. Of these groups, Cisco supports DH groups 1, 2, and 5. RFC 3526 describes DH group 5 and groups 14 through 18. Cisco supports DH groups 5, 14, 15, and 16. RFC 5114 covers DH groups 19 through 26. Of these DH groups, Cisco supports 19, 20, 21, and 24. The following is a list of the DH groups supported by Cisco:
1: Diffie-Hellman group 1 (768 bit)
2: Diffie-Hellman group 2 (1024 bit)
5: Diffie-Hellman group 5 (1536 bit)
14: Diffie-Hellman group 14 (2048 bit)
15: Diffie-Hellman group 15 (3072 bit)
16: Diffie-Hellman group 16 (4096 bit)
19: Diffie-Hellman group 19 (256-bit ECP)
20: Diffie-Hellman group 20 (384-bit ECP)
21: Diffie-Hellman group 21 (521-bit ECP)
24: Diffie-Hellman group 24 (2048 bit, 256-bit subgroup)
ISAKMP and OAKLEY create an authenticated, secure tunnel between two entities, and then negotiate the SA for IPSec. Both peers must authenticate each other and establish a shared key.
Three authentication methods are available: RSA signatures (PKI), RSA encrypted pseudorandom numbers (nonces), and preshared keys (PSK). The DH protocol is used to agree on a common session key.
IPSec uses a different shared key from ISAKMP and OAKLEY. The IPSec shared key can be derived by using DH again to ensure Perfect Forward Secrecy (PFS) or by refreshing the shared secret derived from the original DH exchange.
IKE is a hybrid protocol that establishes a shared security policy and authenticated keys for services that require keys, such as IPSec. Before an IPSec tunnel is established, each device must be able to identify its peer. ISAKMP and IKE are both used interchangeably; however, these two items are somewhat different. IKE was originally defined by RFC 2409. IKE version 2 is currently described by RFC 7296.
IKE Phase 1: The two ISAKMP peers establish a secure and an authenticated channel. This channel is known as the ISAKMP SA. There are two modes defined by ISAKMP: Main Mode and Aggressive Mode.
IKE Phase 2: SAs are negotiated on behalf of services such as IPSec that need keying material. This phase is called Quick Mode.
To configure IKE Phase 1, you need to configure ISAKMP policies. It is possible to configure multiple policies with different configuration statements and then let the two hosts negotiate the policies. The first matched policy on the responder will be used.
Let’s start configuring Phase 1 on both routers:
On R1: R1(config)# crypto isakmp policy 10 R1(config-isakmp)# hash md5 R1(config-isakmp)# authentication pre-share R1(config-isakmp)# group 2 R1(config-isakmp)# encryption 3des R1(config-isakmp)# exit
The IP address of a loopback interface can be used when there are multiple paths to reach the peer’s IP address:
R1(config)# crypto isakmp key cisco address 12.1.1.2 On R2: R2(config)# crypto isakmp policy 10 R2(config-isakmp)# hash md5 R2(config-isakmp)# authentication pre-share R2(config-isakmp)# group 2 R2(config-isakmp)# encryption 3des R2(config-isakmp)# exit R2(config)# crypto isakmp key cisco address 12.1.1.1
To configure the Phase 2, we need to define the transform-set, which specifies the hashing, the security protocol, and the encryption used for Phase 2:
On Both Routers: Rx(config)# crypto ipsec transform-set TSET esp-3des esp-md5-hmac Rx(cfg-config-trans)# exit
Next, we need to define the crypto ACL/proxy ID, which defines the interesting traffic:
On R1: R1(config)# access-list 100 permit ip host 1.1.1.1 host 2.2.2.2 On R2: R2(config)# access-list 100 permit ip host 2.2.2.2 host 1.1.1.1
In the last step, a crypto map is configured to specify the peer, crypto ACL, and the transform set. There are three choices when configuring the following crypto map:
IPSec-ISAKMP: This is the best option. It states that we are using ISAKMP to encrypt and decrypt the key.
IPSec-manual: This is the worst choice. It means that the key needs to be entered manually. (Can you imagine entering a 512-bit key manually?)
GDOI: This choice is used for GETVPN configuration. It stands for group domain of interpretation.
On R1: R1(config)# crypto map TST 10 ipsec-isakmp
You should see the following console message:
% NOTE: This new crypto map will remain disabled until a peer
and a valid access list have been configured.
R1(config-crypto-map)# set peer 12.1.1.2
R1(config-crypto-map)# match address 100
R1(config-crypto-map)# set transform-set TSET
R1(config-crypto-map)# exit
On R2:
R2(config)# crypto map TST 10 ipsec-isakmp
R2(config-crypto-map)# set peer 12.1.1.1
R2(config-crypto-map)# match address 100
R2(config-crypto-map)# set transform-set TSET
R2(config-crypto-map)# exit
The final step applies the crypto map to the interface facing the other peer:
On R1: R1(config)# interface Serial 1/2 R1(config-if)# crypto map TST
You should see the following console message:
%CRYPTO-6-ISAKMP_ON_OFF: ISAKMP is ON On R2: R2(config)# interface Serial 1/1 R2(config-if)# crypto map TST
Let’s verify the configuration before testing:
On R1:
R1# show crypto isakmp policy
Global IKE policy
Protection suite of priority 10
encryption algorithm: Three key triple DES
hash algorithm: Message Digest 5
authentication method: Pre-Shared Key
Diffie-Hellman group: # 2 (1024 bit)
lifetime: 86400 seconds, no volume limit
R1# show crypto isakmp key
Keyring Hostname/Address Preshared Key
default 12.1.1.2 cisco
Now we can test the configuration:
On R1: R1# debug crypto isakmp Crypto ISAKMP debugging is on R1# debug crypto ipsec Crypto IPSEC debugging is on R1# ping 2.2.2.2 source loopback0 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds: Packet sent with a source address of 1.1.1.1
The first ICMP packet triggers the ISAKMP process, as this is our interesting traffic matching the configured crypto ACL.
Before we actually start sending IKE packets to the peer, the router first checks whether there is a local SA (security association) matching that traffic. This check is against the IPSec SA and not an IKE SA.
We can see the outbound and remote IP addresses, port number, local proxy, and remote proxy. The protocol used is ESP, and the transform-set is the default mode of tunnel.
IPSEC(sa_request): ,
(key eng. msg.) OUTBOUND local= 12.1.1.1:500, remote= 12.1.1.2:500,
local_proxy= 1.1.1.1/255.255.255.255/0/0 (type=1),
remote_proxy= 2.2.2.2/255.255.255.255/0/0 (type=1),
protocol= ESP, transform= esp-3des esp-md5-hmac (Tunnel),
lifedur= 3600s and 4608000kb,
spi= 0x0(0), conn_id= 0, keysize= 0, flags= 0x0
The following highlighted line specifies that no SA was found. The router first tried to find an IPSec SA matching the outgoing connection, but it failed to find one.
ISAKMP:(0): SA request profile is (NULL) ISAKMP: Created a peer struct for 12.1.1.2, peer port 500 ISAKMP: New peer created peer = 0x4B24E100 peer_handle = 0x80000003 ISAKMP: Locking peer struct 0x4B24E100, refcount 1 for isakmp_initiator ISAKMP: local port 500, remote port 500 ISAKMP: set new node 0 to QM_IDLE ISAKMP: Find a dup sa in the avl tree during calling isadb_insert sa = 4B331BEC
IKE Phase 1 (Main Mode) Message 1
By default, IKE Main Mode is used, so we should expect six packets for Phase 1. The following highlighted message states that the Aggressive Mode cannot start. However, this does not mean that we are experiencing errors; it just means that Aggressive Mode is not configured on the local router.
ISAKMP:(0):Can not start Aggressive mode, trying Main mode.
The router checks for the configured ISAKMP policy and sees that pre-shared key (PSK) authentication is configured. It has to check whether there is a key for the configured peer as well. After that, the first IKE packet is sent out to the peer’s IP address on port UDP 500.
The packet contains locally configured ISAKMP policies to be negotiated by the peer. The pre-shared key for the remote peer is found, which means that ISAKMP is going to use it to authenticate the peer. This will happen in the last stage of IKE Phase 1.
ISAKMP:(0):found peer pre-shared key matching 12.1.1.2 ISAKMP:(0): constructed NAT-T vendor-rfc3947 ID ISAKMP:(0): constructed NAT-T vendor-07 ID ISAKMP:(0): constructed NAT-T vendor-03 ID ISAKMP:(0): constructed NAT-T vendor-02 ID ISAKMP:(0):Input = IKE_MESG_FROM_IPSEC, IKE_SA_REQ_MM ISAKMP:(0):Old State = IKE_READY New State = IKE_I_MM1 ISAKMP:(0): beginning Main Mode exchange ISAKMP:(0): sending packet to 12.1.1.2 my_port 500 peer_port 500 (I) MM_NO_STATE
The router initiating the IKE exchange is called the initiator, and the router responding to IKE request is called the responder. The initiator (R1) has sent the ISAKMP policy along with vendor-specific IDs that are part of the IKE packet payload. MM_NO_STATE indicates that ISAKMP SA has been created, but nothing else has happened yet.
IKE Phase 1 (Main Mode) Message 2
It looks like everything is going smoothly. We received a response packet from the peer. However, this is one area where things can typically go wrong.
The received packet contains the SA chosen by the peer and some other useful information, such as vendor IDs. Those vendor-specific payloads are used to discover network address translation (NAT) along the path and to maintain keepalives. The router matches the ISAKMP policy from the packet to one that’s locally configured. If there is a match, the tunnel-establishment process continues. If the policy configured on both routers is not the same, the crosscheck process fails and the tunnel is down.
ISAKMP:(0):Sending an IKE IPv4 Packet. ISAKMP (0): received packet from 12.1.1.2 dport 500 sport 500 Global (I) MM_NO_STATE ISAKMP:(0):Input = IKE_MESG_FROM_PEER, IKE_MM_EXCH ISAKMP:(0):Old State = IKE_I_MM1 New State = IKE_I_MM2 ISAKMP:(0): processing SA payload. message ID = 0 ISAKMP:(0): processing vendor id payload ISAKMP:(0): vendor ID seems Unity/DPD but major 69 mismatch ISAKMP (0): vendor ID is NAT-T RFC 3947 ISAKMP:(0):found peer pre-shared key matching 12.1.1.2 ISAKMP:(0): local preshared key found ISAKMP : Scanning profiles for xauth ... IS.!!!! Success rate is 80 percent (4/5), round-trip min/avg/max = 44/45/48 ms
The router is processing ISAKMP parameters that have been sent as the reply. The vendor IDs are processed to determine whether the peer supports the NAT-Traversal, Dead Peer Detection feature. ISAKMP policy is checked against policies defined locally. The atts are acceptable message indicates that the ISAKMP policy matches with remote peer:
R1# AKMP:(0):Checking ISAKMP transform 1 against priority 10 policy ISAKMP: encryption 3DES-CBC ISAKMP: hash MD5 ISAKMP: default group 2 ISAKMP: auth pre-share ISAKMP: life type in seconds ISAKMP: life duration (VPI) of 0x0 0x1 0x51 0x80 ISAKMP:(0):atts are acceptable. Next payload is 0
The lifetime timer has been started. Note that default value is used (86,400 seconds). This is the lifetime for ISAKMP SA. Note that IPSec SAs have their own lifetime parameters, which may be defined as number of seconds or kilobytes of transmitted traffic.
ISAKMP:(0):Acceptable atts:actual life: 0 ISAKMP:(0):Acceptable atts:life: 0 ISAKMP:(0):Fill atts in sa vpi_length:4 ISAKMP:(0):Fill atts in sa life_in_seconds:86400 ISAKMP:(0):Returning Actual lifetime: 86400 ISAKMP:(0)::Started lifetime timer: 86400. ISAKMP:(0): processing vendor id payload ISAKMP:(0): vendor ID seems Unity/DPD but major 69 mismatch ISAKMP (0): vendor ID is NAT-T RFC 3947 ISAKMP:(0):Input = IKE_MESG_INTERNAL, IKE_PROCESS_MAIN_MODE ISAKMP:(0):Old State = IKE_I_MM2 New State = IKE_I_MM2
IKE Phase 1 (Main Mode) Message 3
The third message is sent out containing key-exchange (KE) information for the Diffie-Hellman (DH) secure key-exchange process:
ISAKMP:(0): sending packet to 12.1.1.2 my_port 500 peer_port 500 (I) MM_SA_SETUP ISAKMP:(0):Sending an IKE IPv4 Packet. ISAKMP:(0):Input = IKE_MESG_INTERNAL, IKE_PROCESS_COMPLETE ISAKMP:(0):Old State = IKE_I_MM2 New State = IKE_I_MM3
IKE Phase 1 (Main Mode) Message 4
The fourth message has been received from the peer. This message contains the KE payload, and based on that information, both peers can generate a common session key to be used in securing further communication. The pre-shared key configured locally for the peer is used in this calculation.
After receiving this message, peers can determine whether there is NAT along the path.
ISAKMP (0): received packet from 12.1.1.2 dport 500 sport 500 Global (I) MM_SA_SETUP ISAKMP:(0):Input = IKE_MESG_FROM_PEER, IKE_MM_EXCH ISAKMP:(0):Old State = IKE_I_MM3 New State = IKE_I_MM4 ISAKMP:(0): processing KE payload. message ID = 0 ISAKMP:(0): processing NONCE payload. message ID = 0 ISAKMP:(0):found peer pre-shared key matching 12.1.1.2 ISAKMP:(1002): processing vendor id payload ISAKMP:(1002): vendor ID is Unity ISAKMP:(1002): processing vendor id payload ISAKMP:(1002): vendor ID is DPD ISAKMP:(1002): processing vendor id payload ISAKMP:(1002): speaking to another IOS box! ISAKMP:received payload type 20 ISAKMP (1002): His hash no match - this node outside NAT ISAKMP:received payload type 20 ISAKMP (1002): No NAT Found for self or peer ISAKMP:(1002):Input = IKE_MESG_INTERNAL, IKE_PROCESS_MAIN_MODE ISAKMP:(1002):Old State = IKE_I_MM4 New State = IKE_I_MM4
IKE Phase 1 (Main Mode) Message 5
The fifth message is used for sending out authentication information to the peer. This information is transmitted under the protection of the common shared secret.
ISAKMP:(1002):Send initial contact
ISAKMP:(1002):SA is doing pre-shared key authentication using id type ID_IPV4_ADDR
ISAKMP (1002): ID payload
next-payload : 8
type : 1
address : 12.1.1.1
protocol : 17
port : 500
length : 12
ISAKMP:(1002):Total payload length: 12
ISAKMP:(1002): sending packet to 12.1.1.2 my_port 500 peer_port 500 (I) MM_KEY_EXCH
MM_KEY_EXCH indicates that the peers have exchanged Diffie-Hellman public keys and have generated a shared secret. The ISAKMP SA remains unauthenticated. Note that the process of authentication has just been started.
ISAKMP:(1002):Sending an IKE IPv4 Packet. ISAKMP:(1002):Input = IKE_MESG_INTERNAL, IKE_PROCESS_COMPLETE ISAKMP:(1002):Old State = IKE_I_MM4 New State = IKE_I_MM5
IKE Phase 1 (Main Mode) Message 6
The peer identity is verified by the local router and the SA is established. This message finishes ISAKMP Main Mode (Phase I), and the status is changed to IKE_P1_COMPLETE.
ISAKMP (1002): received packet from 12.1.1.2 dport 500 sport 500 Global (I) MM_KEY_EXCH
ISAKMP:(1002): processing ID payload. message ID = 0
ISAKMP (1002): ID payload
next-payload : 8
type : 1
address : 12.1.1.2
protocol : 17
port : 500
length : 12
ISAKMP:(0):: peer matches *none* of the profiles
ISAKMP:(1002): processing HASH payload. message ID = 0
ISAKMP:(1002):SA authentication status:
authenticated
ISAKMP:(1002):SA has been authenticated with 12.1.1.2
ISAKMP: Trying to insert a peer 12.1.1.1/12.1.1.2/500/, and inserted successfully 4B24E100.
ISAKMP:(1002):Input = IKE_MESG_FROM_PEER, IKE_MM_EXCH
ISAKMP:(1002):Old State = IKE_I_MM5 New State = IKE_I_MM6
ISAKMP:(1002):Input = IKE_MESG_INTERNAL, IKE_PROCESS_MAIN_MODE
ISAKMP:(1002):Old State = IKE_I_MM6 New State = IKE_I_MM6
ISAKMP:(1002):Input = IKE_MESG_INTERNAL, IKE_PROCESS_COMPLETE
ISAKMP:(1002):Old State = IKE_I_MM6 New State = IKE_P1_COMPLETE
IKE Phase 2 (Quick Mode) Message 1
Now it’s time for Phase 2, which is Quick Mode (QM). The router sends out the packet containing local proxy IDs (network/host addresses to be protected by the IPSec tunnel) and the security policy defined by the transform set.
The state of IKE is QM_IDLE. This indicates that the ISAKMP SA is idle. It remains authenticated with its peer and may be used for subsequent Quick Mode exchanges. It is in a quiescent state.
ISAKMP:(1002):beginning Quick Mode exchange, M-ID of 623921701 ISAKMP:(1002):QM Initiator gets spi ISAKMP:(1002): sending packet to 12.1.1.2 my_port 500 peer_port 500 (I) QM_IDLE ISAKMP:(1002):Sending an IKE IPv4 Packet. ISAKMP:(1002):Node 623921701, Input = IKE_MESG_INTERNAL, IKE_INIT_QM ISAKMP:(1002):Old State = IKE_QM_READY New State = IKE_QM_I_QM1 ISAKMP:(1002):Input = IKE_MESG_INTERNAL, IKE_PHASE1_COMPLETE ISAKMP:(1002):Old State = IKE_P1_COMPLETE New State = IKE_P1_COMPLETE ISAKMP (1002): received packet from 12.1.1.2 dport 500 sport 500 Global (I) QM_IDLE
The routers are negotiating the parameters for the IPSec tunnel that will be used for traffic transmission. These parameters are defined by the crypto ipsec transform-set command.
Note that lifetime values of the IPSec SA are visible at this moment. You are able to set this both globally and in the crypto map entry. The attr are acceptable message indicates that the IPSec parameters defined as the IPSec transform-set match on both sides.
ISAKMP:(1002): processing HASH payload. message ID = 623921701
ISAKMP:(1002): processing SA payload. message ID = 623921701
ISAKMP:(1002):Checking IPSec proposal 1
ISAKMP: transform 1, ESP_3DES
ISAKMP: attributes in transform:
ISAKMP: encaps is 1 (Tunnel)
ISAKMP: SA life type in seconds
ISAKMP: SA life duration (basic) of 3600
ISAKMP: SA life type in kilobytes
ISAKMP: SA life duration (VPI) of 0x0 0x46 0x50 0x0
ISAKMP: authenticator is HMAC-MD5
ISAKMP:(1002):atts are acceptable.
IPSEC(validate_proposal_request): proposal part # 1
IPSEC(validate_proposal_request): proposal part # 1,
(key eng. msg.) INBOUND local= 12.1.1.1:0, remote= 12.1.1.2:0,
local_proxy= 1.1.1.1/255.255.255.255/0/0 (type=1),
remote_proxy= 2.2.2.2/255.255.255.255/0/0 (type=1),
protocol= ESP, transform= NONE (Tunnel),
lifedur= 0s and 0kb,
spi= 0x0(0), conn_id= 0, keysize= 0, flags= 0x0
Crypto mapdb : proxy_match
src addr : 1.1.1.1
dst addr : 2.2.2.2
protocol : 0
src port : 0
dst port : 0
ISAKMP:(1002): processing NONCE payload. message ID = 623921701
ISAKMP:(1002): processing ID payload. message ID = 623921701
ISAKMP:(1002): processing ID payload. message ID = 623921701
The local and remote proxies are defined. This indicates the sources and destinations set in crypto ACL, which defines the interesting traffic for the IPSec tunnel. Remember that it is enough when only one entry is mirrored. If not, you may get the following entry in the debug output: PSEC(initialize_sas): invalid proxy IDs.
ISAKMP:(1002): Creating IPSec SAs
inbound SA from 12.1.1.2 to 12.1.1.1 (f/i) 0/ 0
(proxy 2.2.2.2 to 1.1.1.1)
has spi 0x2E5593AE and conn_id 0
lifetime of 3600 seconds
lifetime of 4608000 kilobytes
outbound SA from 12.1.1.1 to 12.1.1.2 (f/i) 0/0
(proxy 1.1.1.1 to 2.2.2.2)
has spi 0x5AEFD96D and conn_id 0
lifetime of 3600 seconds
lifetime of 4608000 kilobytes
The IPSec SAs have been created and inserted into the router’s security associations database (SADB). SAs are distinguished by Security Parameter Index (SPI) values, which are also used to differentiate many tunnels terminated on the same router. Note that two SPI values are generated for one tunnel: one SPI for the inbound SA and one SPI for the outbound SA.
The SPI value is inserted in the ESP header of the packet leaving the router. At the other side of the tunnel, the SPI value inserted into the ESP header enables the router to reach parameters and keys that have been dynamically agreed upon during IKE negotiations, or session key refreshment in case of lifetime timeout.
ISAKMP:(1002): sending packet to 12.1.1.2 my_port 500 peer_port 500 (I) QM_IDLE
ISAKMP:(1002):Sending an IKE IPv4 Packet.
ISAKMP:(1002):deleting node 623921701 error FALSE reason "No Error"
ISAKMP:(1002):Node 623921701, Input = IKE_MESG_FROM_PEER, IKE_QM_EXCH
ISAKMP:(1002):Old State = IKE_QM_I_QM1 New State = IKE_QM_PHASE2_COMPLETE
IPSEC(key_engine): got a queue event with 1 KMI message(s)
Crypto mapdb : proxy_match
src addr : 1.1.1.1
dst addr : 2.2.2.2
protocol : 0
src port : 0
dst port : 0
IPSEC(crypto_ipsec_sa_find_ident_head): reconnecting with the same proxies and peer 12.1.1.2
IPSEC(policy_db_add_ident): src 1.1.1.1, dest 2.2.2.2, dest_port 0
IPSEC(create_sa): sa created,
(sa) sa_dest= 12.1.1.1, sa_proto= 50,
sa_spi= 0x2E5593AE(777360302),
sa_trans= esp-3des esp-md5-hmac , sa_conn_id= 2003
sa_lifetime(k/sec)= (4571378/3600)
IPSEC(create_sa): sa created,
(sa) sa_dest= 12.1.1.2, sa_proto= 50,
sa_spi= 0x5AEFD96D(1525668205),
sa_trans= esp-3des esp-md5-hmac , sa_conn_id= 2004
sa_lifetime(k/sec)= (4571378/3600)
IPSEC(update_current_outbound_sa): get enable SA peer 12.1.1.2 current outbound sa to SPI 5AEFD96D
IPSEC(update_current_outbound_sa): updated peer 12.1.1.2 current outbound sa to SPI 5AEFD96D
ISAKMP:(1001):purging SA., sa=4B23D6D0, delme=4B23D6D0
R1# show crypto isakmp sa
IPv4 Crypto ISAKMP SA
dst src state conn-id status
12.1.1.2 12.1.1.1 QM_IDLE 1002 ACTIVE
IPv6 Crypto ISAKMP SA
R1# show crypto ipsec sa
interface: Serial1/2
Crypto map tag: TST, local addr 12.1.1.1
protected vrf: (none)
local ident (addr/mask/prot/port): (1.1.1.1/255.255.255.255/0/0)
remote ident (addr/mask/prot/port): (2.2.2.2/255.255.255.255/0/0)
current_peer 12.1.1.2 port 500
PERMIT, flags={origin_is_acl,}
# pkts encaps: 4, # pkts encrypt: 4, # pkts digest: 4
# pkts decaps: 4, # pkts decrypt: 4, # pkts verify: 4
# pkts compressed: 0, # pkts decompressed: 0
# pkts not compressed: 0, # pkts compr. failed: 0
# pkts not decompressed: 0, # pkts decompress failed: 0
# send errors 1, # recv errors 0
local crypto endpt.: 12.1.1.1, remote crypto endpt.: 12.1.1.2
path mtu 1500, ip mtu 1500, ip mtu idb Serial1/2
current outbound spi: 0xE53B1D2(240366034)
PFS (Y/N): N, DH group: none
inbound esp sas:
spi: 0xBDAF9A28(3182402088)
transform: esp-3des esp-md5-hmac ,
in use settings ={Tunnel, }
conn id: 2005, flow_id: NETGX:5, sibling_flags 80000046, crypto map: TST
sa timing: remaining key lifetime (k/sec): (4405715/2686)
IV size: 8 bytes
replay detection support: Y
Status: ACTIVE
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0xE53B1D2(240366034)
transform: esp-3des esp-md5-hmac ,
in use settings ={Tunnel, }
conn id: 2006, flow_id: NETGX:6, sibling_flags 80000046, crypto map: TST
sa timing: remaining key lifetime (k/sec): (4405715/2686)
IV size: 8 bytes
replay detection support: Y
Status: ACTIVE
outbound ah sas:
outbound pcp sas:
Task 2
Erase the startup configuration of the routers and reload them before proceeding to the next lab.