Hello,
I have a network like below for testing remote access VPN to ASA5505 behind C871 router with one public IP address.
PC1 (with VPN client)----Internet-----Modem----C871------ASA5505------PC2
The public IP address is assigned to the outside interface of the C871. The C871 forwards incoming traffic UDP 500, 4500, and esp to the outside interface of the ASA that has a private IP address. The PC1 can establish a secure tunnel to the ASA. However, it is not able to ping or access PC2. PC2 is also not able to ping PC1. The PC1 encrypts packets to PC2 but the ASA does not to PC1. Maybe a NAT problem? I understand removing C871 and just use ASA makes VPN much simpler and easier, but I like to understand why it is not working with the current setup and learn how to troubleshoot and fix it.
Here's the running config for the C871 and ASA. Thanks in advance for your help!
C871:
----------------------------------------------------
version 15.0
no service pad
service timestamps debug datetime msec localtime
service timestamps log datetime msec localtime
service password-encryption
!
hostname router
!
boot-start-marker
boot-end-marker
!
enable password 7 xxxx
!
aaa new-model
!
aaa session-id common
!
clock timezone UTC -8
clock summer-time PDT recurring
!
dot11 syslog
ip source-route
!
ip dhcp excluded-address 192.168.2.1
ip dhcp excluded-address 192.168.2.2
!
ip dhcp pool dhcp-vlan2
network 192.168.2.0 255.255.255.0
default-router 192.168.2.1
!
ip cef
ip domain name xxxx.local
no ipv6 cef
!
multilink bundle-name authenticated
!
password encryption aes
!
username xxxx password 7 xxxx
!
ip ssh version 2
!
interface FastEthernet0
switchport mode trunk
!
interface FastEthernet1
!
interface FastEthernet2
!
interface FastEthernet3
!
interface FastEthernet4
description WAN Interface
ip address 1.1.1.2 255.255.255.252
ip access-group wna-in in
no ip redirects
no ip unreachables
no ip proxy-arp
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
no cdp enable
!
interface Vlan1
no ip address
!
interface Vlan2
description LAN-192.168.2
ip address 192.168.2.1 255.255.255.0
ip nat inside
ip virtual-reassembly
!
interface Vlan10
description router-asa
ip address 10.10.10.1 255.255.255.252
ip nat inside
ip virtual-reassembly
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
ip nat inside source list nat-pat interface FastEthernet4 overload
ip nat inside source static 10.10.10.1 interface FastEthernet4
ip nat inside source static udp 10.10.10.2 500 interface FastEthernet4 500
ip nat inside source static udp 10.10.10.2 4500 interface FastEthernet4 4500
ip nat inside source static esp 10.10.10.2 interface FastEthernet4
ip route 0.0.0.0 0.0.0.0 1.1.1.1
ip route 10.10.10.0 255.255.255.252 10.10.10.2
ip route 192.168.2.0 255.255.255.0 10.10.10.2
!
ip access-list standard ssh
permit 0.0.0.0 255.255.255.0 log
permit any log
!
ip access-list extended nat-pat
deny ip 192.168.2.0 0.0.0.255 192.168.100.0 0.0.0.255
permit ip 192.168.2.0 0.0.0.255 any
ip access-list extended wan-in
deny ip 192.168.0.0 0.0.255.255 any
deny ip 172.16.0.0 0.15.255.255 any
deny ip 10.0.0.0 0.255.255.255 any
deny ip 127.0.0.0 0.255.255.255 any
deny ip 169.255.0.0 0.0.255.255 any
deny ip 255.0.0.0 0.255.255.255 any
deny ip 224.0.0.0 31.255.255.255 any
deny ip host 0.0.0.0 any
deny icmp any any fragments log
permit tcp any any established
permit icmp any any net-unreachable
permit udp any any eq isakmp
permit udp any any eq non500-isakmp
permit esp any any
permit icmp any any host-unreachable
permit icmp any any port-unreachable
permit icmp any any packet-too-big
permit icmp any any administratively-prohibited
permit icmp any any source-quench
permit icmp any any ttl-exceeded
permit icmp any any echo-reply
deny ip any any log
!
control-plane
!
line con 0
exec-timeout 0 0
logging synchronous
no modem enable
line aux 0
line vty 0 4
access-class ssh in
exec-timeout 5 0
logging synchronous
transport input ssh
!
scheduler max-task-time 5000
end
-------------------------------------------------------------------
ASA:
-------------------------------------------------------------------
ASA Version 9.1(2)
!
hostname asa
domain-name xxxx.local
enable password xxxx encrypted
xlate per-session deny tcp any4 any4
xlate per-session deny tcp any4 any6
xlate per-session deny tcp any6 any4
xlate per-session deny tcp any6 any6
xlate per-session deny udp any4 any4 eq domain
xlate per-session deny udp any4 any6 eq domain
xlate per-session deny udp any6 any4 eq domain
xlate per-session deny udp any6 any6 eq domain
passwd xxxx encrypted
names
ip local pool vpn-pool 192.168.100.10-192.168.100.35 mask 255.255.255.0
!
interface Ethernet0/0
switchport trunk allowed vlan 2,10
switchport mode trunk
!
interface Ethernet0/1
switchport access vlan 2
!
interface Ethernet0/2
shutdown
!
interface Ethernet0/3
shutdown
!
interface Ethernet0/4
shutdown
!
interface Ethernet0/5
shutdown
!
interface Ethernet0/6
shutdown
!
interface Ethernet0/7
shutdown
!
interface Vlan1
no nameif
no security-level
no ip address
!
interface Vlan2
nameif inside
security-level 100
ip address 192.168.2.2 255.255.255.0
!
interface Vlan10
nameif outside
security-level 0
ip address 10.10.10.2 255.255.255.252
!
ftp mode passive
clock timezone UTC -8
clock summer-time PDT recurring
dns server-group DefaultDNS
domain-name xxxx.local
object network vlan2-mapped
subnet 192.168.2.0 255.255.255.0
object network vlan2-real
subnet 192.168.2.0 255.255.255.0
object network vpn-192.168.100.0
subnet 192.168.100.0 255.255.255.224
object network lan-192.168.2.0
subnet 192.168.2.0 255.255.255.0
access-list no-nat-in extended permit ip 192.168.2.0 255.255.255.0 192.168.100.0 255.255.255.0
access-list vpn-split extended permit ip 192.168.2.0 255.255.255.0 any
pager lines 24
logging enable
logging asdm informational
mtu inside 1500
mtu outside 1500
no failover
icmp unreachable rate-limit 1 burst-size 1
no asdm history enable
arp timeout 14400
no arp permit-nonconnected
nat (inside,outside) source static lan-192.168.2.0 lan-192.168.2.0 destination static vpn-192.168.100.0 vpn-192.168.100.0 no-proxy-arp route-lookup
!
object network vlan2-real
nat (inside,outside) static vlan2-mapped
route outside 0.0.0.0 0.0.0.0 10.10.10.1 1
timeout xlate 3:00:00
timeout pat-xlate 0:00:30
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
timeout tcp-proxy-reassembly 0:01:00
timeout floating-conn 0:00:00
dynamic-access-policy-record DfltAccessPolicy
user-identity default-domain LOCAL
aaa authentication ssh console LOCAL
aaa authentication http console LOCAL
http server enable
http 192.168.2.0 255.255.255.0 inside
http 10.10.10.1 255.255.255.255 outside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart warmstart
crypto ipsec ikev1 transform-set ESP-AES-256-SHA esp-aes-256 esp-sha-hmac
crypto ipsec security-association pmtu-aging infinite
crypto dynamic-map SYSTEM_DEFAULT_CRYPTO_MAP 65535 set pfs group1
crypto dynamic-map SYSTEM_DEFAULT_CRYPTO_MAP 65535 set ikev1 transform-set ESP-AES-256-SHA
crypto dynamic-map SYSTEM_DEFAULT_CRYPTO_MAP 65535 set reverse-route
crypto map outside_map 65535 ipsec-isakmp dynamic SYSTEM_DEFAULT_CRYPTO_MAP
crypto map outside_map interface outside
crypto ca trustpool policy
crypto ikev1 enable outside
crypto ikev1 policy 30
authentication pre-share
encryption aes-256
hash sha
group 2
lifetime 86400
telnet timeout 5
ssh 192.168.2.0 255.255.255.0 inside
ssh 10.10.10.1 255.255.255.255 outside
ssh timeout 20
ssh version 2
ssh key-exchange group dh-group1-sha1
console timeout 0
threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
webvpn
anyconnect-essentials
group-policy vpn internal
group-policy vpn attributes
dns-server value 8.8.8.8 8.8.4.4
vpn-tunnel-protocol ikev1
split-tunnel-policy tunnelspecified
split-tunnel-network-list value vpn-split
default-domain value xxxx.local
username xxxx password xxxx encrypted privilege 15
tunnel-group vpn type remote-access
tunnel-group vpn general-attributes
address-pool vpn-pool
default-group-policy vpn
tunnel-group vpn ipsec-attributes
ikev1 pre-shared-key xxxx
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
message-length maximum client auto
message-length maximum 512
policy-map global_policy
class inspection_default
inspect dns preset_dns_map
inspect ftp
inspect h323 h225
inspect h323 ras
inspect ip-options
inspect netbios
inspect rsh
inspect rtsp
inspect skinny
inspect esmtp
inspect sqlnet
inspect sunrpc
inspect tftp
inspect sip
inspect xdmcp
inspect icmp
!
service-policy global_policy global
prompt hostname context
no call-home reporting anonymous
call-home
profile CiscoTAC-1
no active
destination address http https://tools.cisco.com/its/service/oddce/services/DDCEService
destination address email callhome@cisco.com
destination transport-method http
subscribe-to-alert-group diagnostic
subscribe-to-alert-group environment
subscribe-to-alert-group inventory periodic monthly
subscribe-to-alert-group configuration periodic monthly
subscribe-to-alert-group telemetry periodic daily
Cryptochecksum:40c05c90210242a42b7dbfe9bda79ce2
: end
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