10-18-2023 06:17 PM
I am trying to create a network comprising of two routers, one ASA 5505 firewall, one computer and one web server.
I have created a VPN tunnel in between Router4 and ASA5505 firewall. I have also configured both the routers and the ASA5505 firewall.
Also i read on the internet that i have to initiate interesting traffic for VPN to initialize. But I don't really understand what it means.
Below are the configuration of the router4:
Router(config)#exit
Router#
%SYS-5-CONFIG_I: Configured from console by console
show run
Building configuration...
Current configuration : 1226 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Router
!
!
!
!
!
!
!
!
ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO1941/K9 sn FTX15247V2V-
license boot module c1900 technology-package securityk9
!
!
!
crypto isakmp policy 10
encr aes
authentication pre-share
group 5
lifetime 28800
!
crypto isakmp key 12345 address 192.168.2.1
!
!
!
crypto ipsec transform-set R1->ASA esp-aes esp-sha-hmac
!
crypto map IPSEC-MAP 10 ipsec-isakmp
! Incomplete
set peer 192.168.2.1
set transform-set R1->ASA
match address VPN-TRAFFIC
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0
ip address 192.168.4.1 255.255.255.0
duplex auto
speed auto
!
interface GigabitEthernet0/1
ip address 192.168.3.2 255.255.255.0
duplex auto
speed auto
crypto map IPSEC-MAP
!
interface Vlan1
no ip address
shutdown
!
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.3.1
!
ip flow-export version 9
!
!
ip access-list extended VPN-TRAFFIC
access-list 100 permit ip host 192.168.4.2 host 192.168.1.2
access-list 100 permit ip host 192.168.1.2 host 192.168.4.2
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
!
!
!
end
Router#
And ASA5505 firewall configuration are as follows:
ciscoasa#show run
: Saved
:
ASA Version 8.4(2)
!
hostname ciscoasa
names
!
interface Ethernet0/0
switchport access vlan 2
!
interface Ethernet0/1
!
interface Ethernet0/2
!
interface Ethernet0/3
!
interface Ethernet0/4
!
interface Ethernet0/5
!
interface Ethernet0/6
!
interface Ethernet0/7
!
interface Vlan1
nameif inside
security-level 100
ip address 192.168.1.1 255.255.255.0
!
interface Vlan2
nameif outside
security-level 0
ip address 192.168.2.1 255.255.255.0
!
object network local-network
!
route outside 0.0.0.0 0.0.0.0 192.168.2.2 1
!
access-list VPN-TRAFFIC extended permit ip 192.168.1.0 255.255.255.0 192.168.4.0 255.255.255.0
access-list VPN-TRAFFIC extended permit icmp 192.168.4.0 255.255.255.0 192.168.1.0 255.255.255.0
!
!
!
!
!
!
!
telnet timeout 5
ssh timeout 5
!
dhcpd auto_config outside
!
dhcpd address 192.168.1.5-192.168.1.36 inside
dhcpd enable inside
!
!
!
crypto ipsec ikev1 transform-set ASA->R1 esp-aes esp-sha-hmac
!
crypto map IPSEC-MAP 10 match address VPN-TRAFFIC
crypto map IPSEC-MAP 10 set peer 192.168.3.2
crypto map IPSEC-MAP 10 set ikev1 transform-set ASA->R1
crypto map IPSEC-MAP interface outside
crypto ikev1 enable outside
crypto ikev1 policy 10
encr aes
authentication pre-share
group 5
lifetime 28800
!
tunnel-group 192.168.3.2 type ipsec-l2l
tunnel-group 192.168.3.2 ipsec-attributes
ikev1 pre-shared-key 12345
!
ciscoasa#
10-18-2023 10:39 PM - edited 10-18-2023 10:40 PM
Hello @heymastreo,
The interesting traffic for the VPN tunnel is defined by the "VPN-TRAFFIC" access lists on both devices, allowing traffic between the specified subnets (192.168.1.0/24 and 192.168.4.0/24) to trigger the VPN connection. To initiate the VPN tunnel, you need to send traffic between these subnets (for example, by pinging a device in the remote network from the local network). Once the devices detect the interesting traffic, the VPN tunnel should establish automatically.
10-19-2023 02:23 AM
I tried pinging from server to pc using `ping -t 192.168.4.2` but it doesn't work
10-18-2023 11:02 PM
Router
Share this
10-19-2023 02:22 AM - edited 10-19-2023 02:37 AM
Router#show crypto isakmp sa
IPv4 Crypto ISAKMP SA
dst src state conn-id slot status
192.168.2.1 192.168.3.2 QM_IDLE 1087 0 ACTIVE (deleted)
IPv6 Crypto ISAKMP SA
Router#
10-19-2023 02:24 AM
Can yoh ping from R to ASA outside interface?
I.e. ping from vpn endpoint to endpoint
10-19-2023 02:41 AM
I think I can
10-19-2023 02:41 AM
That great
Meaning phase1 is OK
Phase2 now need to check
Show crypto ipsec
Share this output of router
10-19-2023 02:42 AM
output of `show crypto ipsec sa` on router
Router#show crypto ipsec sa
interface: GigabitEthernet0/1
Crypto map tag: IPSEC-MAP, local addr 192.168.3.2
protected vrf: (none)
local ident (addr/mask/prot/port): (192.168.4.0/255.255.255.0/0/0)
remote ident (addr/mask/prot/port): (192.168.1.0/255.255.255.0/0/0)
current_peer 192.168.2.1 port 500
PERMIT, flags={origin_is_acl,}
#pkts encaps: 32, #pkts encrypt: 32, #pkts digest: 0
#pkts decaps: 27, #pkts decrypt: 27, #pkts verify: 0
#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.: 192.168.3.2, remote crypto endpt.:192.168.2.1
path mtu 1500, ip mtu 1500, ip mtu idb GigabitEthernet0/1
current outbound spi: 0x55C37018(1438871576)
inbound esp sas:
spi: 0xD5C1765B(3586225755)
transform: esp-aes esp-sha-hmac ,
in use settings ={Tunnel, }
conn id: 2005, flow_id: FPGA:1, crypto map: IPSEC-MAP
sa timing: remaining key lifetime (k/sec): (4525504/3078)
IV size: 16 bytes
replay detection support: N
Status: ACTIVE
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x55C37018(1438871576)
transform: esp-aes esp-sha-hmac ,
in use settings ={Tunnel, }
conn id: 2006, flow_id: FPGA:1, crypto map: IPSEC-MAP
sa timing: remaining key lifetime (k/sec): (4525504/3078)
IV size: 16 bytes
replay detection support: N
Status: ACTIVE
outbound ah sas:
outbound pcp sas:
Router#
10-19-2023 02:47 AM
#pkts encaps: 32, #pkts encrypt: 32, #pkts digest: 0
#pkts decaps: 27, #pkts decrypt: 27, #pkts verify: 0
There packet encrypt decrypt so vpn is OK
Check gw in Server and PC.
Also since there is asa you need to allow ping via
inspect icmp under global policy of asa.
I think this is issue here
10-19-2023 02:52 AM
These are the access-lists I have on my asa for now
ciscoasa#show access-list
access-list cached ACL log flows: total 0, denied 0 (deny-flow-max 4096) alert-interval 300
access-list VPN-TRAFFIC; 2 elements; name hash: 0x2679b677
access-list VPN-TRAFFIC line 1 extended permit ip 192.168.1.0 255.255.255.0 192.168.4.0 255.255.255.0(hitcnt=11) 0xd9419465
access-list VPN-TRAFFIC line 2 extended permit icmp 192.168.4.0 255.255.255.0 192.168.1.0 255.255.255.0(hitcnt=0) 0x478a1876
ciscoasa#
10-19-2023 02:56 AM
This acl for vpn remove second line
access-list VPN-TRAFFIC line 2 extended permit icmp 192.168.4.0 255.255.255.0 192.168.1.0 255.255.255.0(hitcnt=0)
And Add inspect icmp
10-19-2023 03:02 AM
`inspect icmp` does not seem to be working. It gives invalid input detected error
10-19-2023 03:06 AM
10-19-2023 03:26 AM - edited 10-19-2023 03:27 AM
I was able to add inspect icmp in asa but i have no idea what to do after this.
Edit:
This is what i got after i ping from one end point of vpn to another
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