10

Update

Finally got upgraded to 9.1.4. I got everything configured, reenabled VPN, and was still having the same problem. So, I cleared all VPN config information and started from scratch. Below is my current config. I am able to connect and access resources on the internal network. I am not, however, able to access the internet through the VPN.

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
ip local pool VPNPool 192.168.3.1-192.168.3.30
!
interface Ethernet0/0
 switchport access vlan 2
!
interface Ethernet0/1
 switchport access vlan 2
!
interface Ethernet0/2
 switchport access vlan 2
!
interface Ethernet0/3
!
interface Ethernet0/4
!
interface Ethernet0/5
!
interface Ethernet0/6
!
interface Ethernet0/7
!
interface Vlan1
 description Private-Interface
 nameif inside
 security-level 100
 ip address 10.3.3.1 255.255.255.0 
!
interface Vlan2
 description Public-Interface
 nameif outside
 security-level 0
 ip address xx.xx.xx.xx 255.255.255.248 
!
boot system disk0:/asa914-k8.bin
object network obj-10.3.3.0
 subnet 10.3.3.0 255.255.255.0
object network vpn_nat
 subnet 192.168.3.0 255.255.255.0
object-group service Internet-udp udp
 description UDP Standard Internet Services
 port-object eq domain
 port-object eq ntp
object-group service Internet-tcp tcp
 description TCP Standard Internet Services
 port-object eq www
 port-object eq https
 port-object eq smtp
 port-object eq 465
 port-object eq pop3
 port-object eq 995
 port-object eq ftp
 port-object eq ftp-data
 port-object eq domain
 port-object eq ssh
object-group network Internal-Subnet
object-group network obj-vpnpool
access-list inside-in remark -=[Access Lists for Outgoing Packets from Inside interface]=-
access-list inside-in extended permit udp 10.3.3.0 255.255.255.0 any4 object-group Internet-udp 
access-list inside-in extended permit tcp 10.3.3.0 255.255.255.0 any4 object-group Internet-tcp 
access-list inside-in extended permit icmp 10.3.3.0 255.255.255.0 any4 
access-list outside-in remark -=[Access Lists for Incoming Packets on OUTSIDE interface]=-
access-list outside-in extended permit icmp any4 any4 echo-reply 
access-list outside-in extended permit icmp any4 any4 echo 
access-list vpn_splitTunnelAcl standard permit 10.3.3.0 255.255.255.0 
nat (inside,outside) source static obj-10.3.3.0 obj-10.3.3.0 destination static vpn_nat vpn_nat no-proxy-arp route-lookup
object network obj-10.3.3.0
 nat (inside,outside) dynamic interface
access-group inside-in in interface inside
access-group outside-in in interface outside
route outside 0.0.0.0 0.0.0.0 xx.xx.xx.xx 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 telnet console LOCAL 
aaa authentication http console LOCAL 
aaa authentication ssh console LOCAL 
http server enable
http 10.3.3.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
crypto ipsec ikev1 transform-set vpn-transform-set-ikev1 esp-3des esp-sha-hmac 
crypto ipsec ikev1 transform-set vpn-transform-set-ikev1 mode transport
crypto ipsec security-association pmtu-aging infinite
crypto dynamic-map dyno 10 set ikev1 transform-set vpn-transform-set-ikev1
crypto map vpn 20 ipsec-isakmp dynamic dyno
crypto map vpn interface outside
crypto ca trustpool policy
crypto isakmp nat-traversal 3600
crypto ikev1 enable outside
crypto ikev1 policy 10
 authentication pre-share
 encryption 3des
 hash sha
 group 2
 lifetime 86400
telnet timeout 5
ssh 10.3.3.0 255.255.255.0 inside
ssh timeout 20
ssh version 2
ssh key-exchange group dh-group1-sha1
console timeout 0



dhcpd address 10.3.3.100-10.3.3.150 inside
dhcpd dns xx.xx.xx.xx xx.xx.xx.xx interface inside
dhcpd enable inside
!
threat-detection basic-threat
threat-detection statistics host number-of-rate 2
threat-detection statistics port number-of-rate 2
threat-detection statistics protocol number-of-rate 2
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
group-policy vpn_policy internal
group-policy vpn_policy attributes
 vpn-tunnel-protocol l2tp-ipsec 
 split-tunnel-policy tunnelspecified
 split-tunnel-network-list value vpn_splitTunnelAcl
username mike password x
username mike attributes
 vpn-tunnel-protocol l2tp-ipsec 
username admin password x encrypted privilege 15
tunnel-group DefaultRAGroup general-attributes
 address-pool VPNPool
 default-group-policy vpn_policy
tunnel-group DefaultRAGroup ipsec-attributes
 ikev1 pre-shared-key *
tunnel-group DefaultRAGroup ppp-attributes
 authentication ms-chap-v2
!
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 
 class class-default
  user-statistics accounting
!
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 [email protected]
  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
: end

Old Stuff

I'm trying to set up an L2TP over IPSec remote access VPN on an ASA 5505, version 8.2(5). I'm able to authenticate and a connection is established. I am not, however, able to access resources on the internal network or access the internet. Furthermore, the ASA is not able to ping connected clients.

On the connected client I can ping the ASA's external IP. When I do that, I even see the encrypted and decrypted packet count go up on the ASA with show crypto ipsec sa.

I've tried doing a few things with NAT and with the routes, but just can't get it working.

My internal network is 10.3.3.0/24 and my VPN pool is 192.168.3.0/24. Below I've copied the relevant portions of the config.


object-group service Internet-udp udp
 description UDP Standard Internet Services
 port-object eq domain
 port-object eq ntp
object-group service Internet-tcp tcp
 description TCP Standard Internet Services
 port-object eq www
 port-object eq https
 port-object eq smtp
 port-object eq 465
 port-object eq pop3
 port-object eq 995
 port-object eq ftp
 port-object eq ftp-data
 port-object eq domain
 port-object eq ssh
 port-object eq 993
object-group network Internal-Subnet
object-group network obj-vpnpool
access-list inside-in remark -=[Access Lists for Outgoing Packets from Inside interface]=-
access-list inside-in extended permit udp 10.3.3.0 255.255.255.0 any object-group Internet-udp
access-list inside-in extended permit tcp 10.3.3.0 255.255.255.0 any object-group Internet-tcp
access-list inside-in extended permit icmp 10.3.3.0 255.255.255.0 any
access-list outside-in remark -=[Access Lists for Incoming Packets on OUTSIDE interface]=-
access-list outside-in extended permit icmp any any echo-reply
access-list DefaultRAGroup_splitTunnelAcl standard permit 10.3.3.0 255.255.255.0
access-list DefaultRAGroup_splitTunnelAcl standard permit 192.168.3.96 255.255.255.224
access-list inside_nat0_outbound extended permit ip 10.3.3.0 255.255.255.0 192.168.3.0 255.255.255.0

ip local pool VPNPool 192.168.3.100-192.168.3.120 mask 255.255.255.0

nat (inside) 0 access-list inside_nat0_outbound
nat (inside) 1 10.3.3.0 255.255.255.0
access-group inside-in in interface inside
access-group outside-in in interface outside
route outside 0.0.0.0 0.0.0.0 **.**.**.** 1

group-policy DefaultRAGroup internal
group-policy DefaultRAGroup attributes
 dns-server value **.**.**.** **.**.**.**
 vpn-tunnel-protocol l2tp-ipsec
 split-tunnel-policy tunnelspecified
 split-tunnel-network-list value DefaultRAGroup_splitTunnelAcl

crypto ipsec transform-set ESP-AES-256-MD5 esp-aes-256 esp-md5-hmac 
crypto ipsec transform-set ESP-DES-SHA esp-des esp-sha-hmac 
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac 
crypto ipsec transform-set ESP-DES-MD5 esp-des esp-md5-hmac 
crypto ipsec transform-set ESP-AES-192-MD5 esp-aes-192 esp-md5-hmac 
crypto ipsec transform-set ESP-3DES-MD5 esp-3des esp-md5-hmac 
crypto ipsec transform-set ESP-AES-256-SHA esp-aes-256 esp-sha-hmac 
crypto ipsec transform-set ESP-AES-128-SHA esp-aes esp-sha-hmac 
crypto ipsec transform-set ESP-AES-192-SHA esp-aes-192 esp-sha-hmac 
crypto ipsec transform-set ESP-AES-128-MD5 esp-aes esp-md5-hmac 
crypto ipsec transform-set TRANS_ESP_3DES_SHA esp-3des esp-sha-hmac 
crypto ipsec transform-set TRANS_ESP_3DES_SHA mode transport
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
crypto dynamic-map SYSTEM_DEFAULT_CRYPTO_MAP 65535 set transform-set TRANS_ESP_3DES_SHA ESP-AES-128-SHA ESP-AES-128-MD5 ESP-AES-192-SHA ESP-AES-192-MD5 ESP-AES-256-SHA ESP-AES-256-MD5 ESP-3DES-SHA ESP-3DES-MD5 ESP-DES-SHA ESP-DES-MD5
crypto map outside_map 65535 ipsec-isakmp dynamic SYSTEM_DEFAULT_CRYPTO_MAP
crypto map outside_map interface outside
crypto isakmp enable outside
crypto isakmp policy 10
 authentication pre-share
 encryption 3des
 hash sha     
 group 2
 lifetime 86400

Update 1

I took Ron's suggestion and learned how the packet-tracer commands function. Here are some things I found after issuing packet-tracer input inside icmp 10.3.3.100 8 0 192.168.3.100


Phase: 1
Type: ROUTE-LOOKUP
Subtype: input
Result: ALLOW
Config:
Additional Information:
in   192.168.3.100   255.255.255.255 outside

Phase: 2
Type: ACCESS-LIST
Subtype: log
Result: ALLOW
Config:
access-group inside-in in interface inside
access-list inside-in extended permit icmp 10.3.3.0 255.255.255.0 any 
Additional Information:

Phase: 3
Type: IP-OPTIONS
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 4      
Type: INSPECT 
Subtype: np-inspect
Result: ALLOW
Config:
Additional Information:

Phase: 5
Type: NAT-EXEMPT
Subtype: 
Result: ALLOW
Config:
  match ip inside 10.3.3.0 255.255.255.0 outside 192.168.3.0 255.255.255.0
    NAT exempt
    translate_hits = 16, untranslate_hits = 2
Additional Information:

Phase: 6
Type: NAT
Subtype: 
Result: ALLOW
Config:
nat (inside) 1 10.3.3.0 255.255.255.0
  match ip inside 10.3.3.0 255.255.255.0 outside any
    dynamic translation to pool 1 (**.**.**.** [Interface PAT])
    translate_hits = 21582, untranslate_hits = 2392
Additional Information:

Phase: 7
Type: NAT
Subtype: host-limits
Result: ALLOW
Config:
nat (inside) 1 10.3.3.0 255.255.255.0
  match ip inside 10.3.3.0 255.255.255.0 inside any
    dynamic translation to pool 1 (No matching global)
    translate_hits = 0, untranslate_hits = 0
Additional Information:

Phase: 8
Type: HOST-LIMIT
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 9
Type: L2TP-PPP
Subtype: 
Result: ALLOW 
Config:
Additional Information:

Phase: 10
Type: PPP
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 11
Type: FLOW-CREATION
Subtype: 
Result: ALLOW
Config:
Additional Information:
New flow created with id 23037, packet dispatched to next module

Result:
input-interface: inside
input-status: up
input-line-status: up
output-interface: outside
output-status: up
output-line-status: up
Action: allow

Phase 6 shows a NAT translation. I then check the echo-reply with packet-tracer input outside icmp 192.168.3.100 0 0 10.3.3.100.


Phase: 1
Type: ROUTE-LOOKUP
Subtype: input
Result: ALLOW
Config:
Additional Information:
in   10.3.3.0        255.255.255.0   inside

Phase: 2
Type: ACCESS-LIST
Subtype: log
Result: ALLOW
Config:
access-group outside-in in interface outside
access-list outside-in extended permit icmp any any echo-reply 
Additional Information:

Phase: 3
Type: IP-OPTIONS
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 4      
Type: CP-PUNT
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 5
Type: L2TP-PPP
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 6
Type: INSPECT
Subtype: np-inspect
Result: ALLOW
Config:
Additional Information:

Phase: 7
Type: VPN
Subtype: ipsec-tunnel-flow
Result: ALLOW 
Config:
Additional Information:

Phase: 8
Type: NAT-EXEMPT
Subtype: rpf-check
Result: ALLOW
Config:
Additional Information:

Phase: 9
Type: HOST-LIMIT
Subtype: 
Result: ALLOW
Config:
Additional Information:

Phase: 10
Type: NAT
Subtype: rpf-check
Result: ALLOW
Config:
nat (inside) 1 10.3.3.0 255.255.255.0
  match ip inside 10.3.3.0 255.255.255.0 outside any
    dynamic translation to pool 1 (**.**.**.** [Interface PAT])
    translate_hits = 21589, untranslate_hits = 2392
Additional Information:

Phase: 11
Type: FLOW-CREATION
Subtype: 
Result: ALLOW
Config:
Additional Information:
New flow created with id 23079, packet dispatched to next module

Result:
input-interface: outside
input-status: up
input-line-status: up
output-interface: inside
output-status: up
output-line-status: up
Action: allow

Phase 8 shows NAT-EXEMPT but Phase 10 shows a NAT translation. That would be problematic.

Update 2

Currently show vpn-sessiondb detail remote filter protocol L2TPOverIPSec returns nothing while a client is connected.

On the other hand show vpn-sessiondb detail remote filter protocol L2TPOverIPSecOverNatT shows the connected client. While trying to do things on the client, the Bytes Rx and Pkts Rx increase. Bytes Tx and Pkts Tx do not increase (Pkts Tx stays at 17). Pkts Tx Drop and Pkts Rx Drop are both 0. If I ping 192.168.3.100 (the vpn client), then Pkts Tx increases for each ping.

Update 3

I enabled logging on the ASA and established a connection. Here are some interesting log messages I'm seeing


%ASA-6-737026: IPAA: Client assigned 192.168.3.100 from local pool
ppp_virtual_interface_id is 1, client_dynamic_ip is 192.168.3.100
%ASA-7-609001: Built local-host outside:192.168.3.100
%ASA-2-106001: Inbound TCP connection denied from 192.168.3.100/57013 to **.**.**.**/443 flags SYN  on interface outside
%ASA-2-106001: Inbound TCP connection denied from 192.168.3.100/57013 to **.**.**.**/443 flags SYN  on interface outside
%ASA-2-106001: Inbound TCP connection denied from 192.168.3.100/57013 to **.**.**.**/443 flags SYN  on interface outside
%ASA-2-106007: Deny inbound UDP from 192.168.3.100/9562 to **.**.**.**/53 due to DNS Query
%ASA-2-106007: Deny inbound UDP from 192.168.3.100/61529 to **.**.**.**/53 due to DNS Query
%ASA-2-106007: Deny inbound UDP from 192.168.3.100/38824 to **.**.**.**/53 due to DNS Query

%ASA-3-713042: IKE Initiator unable to find policy: Intf inside, Src: 10.3.3.100, Dst: 192.168.3.100
%ASA-3-713042: IKE Initiator unable to find policy: Intf inside, Src: 10.3.3.100, Dst: 192.168.3.100
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18
  • Have you tried using the packet tracer feature of the ASA to see where things might be going awry?
    – Ron Trunk
    Commented Feb 9, 2014 at 16:25
  • @Ron to simulate an http packet from the VPN would I use this packet-tracer input outside 192.168.3.100 50612 8.8.8.8 80? I'm confused as to whether I should use outside or inside for VPN traffic.
    – mikeazo
    Commented Feb 10, 2014 at 13:13
  • As an experiment, remove the nat(1) statement and see if it works.
    – Ron Trunk
    Commented Feb 10, 2014 at 17:22
  • 2
    let us continue this discussion in chat
    – Ron Trunk
    Commented Feb 10, 2014 at 18:28
  • 2
    I am not, however, able to access the internet through the VPN. Looks like you're configured for a split tunnel so you won't be using the tunnel for internet traffic. If you tunnel all traffic you should be able to access the internet through the VPN.
    – James.Birmingham
    Commented Mar 21, 2014 at 21:28

4 Answers 4

Reset to default
1

In order for the client to be able to connect to resources outside of the VPN tunnel, a split tunnel must be configured. This will allow the adapter to inherit routes outside of it's own route table as well as allow the traffic out. Adding routes upon connect is only part of the issue.

Here is a link with instructions for the ADM and CLI http://www.cisco.com/c/en/us/support/docs/security/asa-5500-x-series-next-generation-firewalls/70917-asa-split-tunnel-vpn-client.html

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1

All of the answers suggest a split tunnel, which I believe I had setup correctly.

In the end, I setup a proxy server on the internal network. If my browser was pointed at that, then I could access the internet through it.

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0

TO access internet u will have to configure split tunnel, because split tunnel define what traffic will go by tunnel and what will not , because by default all traffic will go by tunnel . u can see on your computer by typing ( print route),that all traffic will go by tunnel , and if u dont want to use split tunnel , then we have one more solution you can configure reverse natting, first packet will go to your remote server and remote server will send back to internet

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0

I suspect that Split Tunneling may not be supported with L2TP over IPSec. Could you try the following for me?

conf t
!
same-security-traffic permit intra-interface
!
object network vpn_nat
 nat (outside,outside) dynamic interface
!

I also noticed the DNS server configuration is missing in your updated Group Policy.

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