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Can not establish L2TP-IPsec connections to remote location.

dclarolh1
Level 1
Level 1

Please help. I can not seem to establish a VPN tunnel from our clients to a remote network. I know it works fine from other locations so their end is taken care of. The VPN client is using L2TP-IPsec.

Here is my config if anyone has a suggestion.

ASA Version 8.2(2)19
!
hostname ****************
domain-name cisco.com
enable password ds4hdW4uvMnfKnfo encrypted
passwd 2KFQnbNIdI.2KYOU encrypted
names
!
interface Ethernet0/0
nameif outside
security-level 0
ip address 10.245.254.2 255.255.255.0
!
interface Ethernet0/1
shutdown
nameif Outside2
security-level 100
no ip address
!
interface Ethernet0/2
nameif inside
security-level 100
ip address 10.245.253.1 255.255.255.0
!
interface Ethernet0/3
shutdown
nameif Inside2
security-level 100
no ip address
!
interface Management0/0
nameif management
security-level 100
ip address 10.245.1.2 255.255.255.0
management-only
!
boot system disk0:/asa822-19-k8.bin
ftp mode passive
dns server-group DefaultDNS
domain-name cisco.com
same-security-traffic permit inter-interface
access-list outside_access_in remark Access Rule to Allow ESP traffic
access-list outside_access_in remark Access Rule to allow ISAKMP to *****
access-list outside_access_in remark Access Rule to allow port 4500 (NAT-T) to ****
access-list outside_access_in remark Access Rule to allow port 1701 (L2TP) to ****
access-list outside_access_in extended permit esp any host x.x.x.x
access-list outside_access_in extended permit udp any eq isakmp host x.x.x.x
access-list outside_access_in extended permit udp any eq 4500 host x.x.x.x
access-list outside_access_in extended permit udp any eq 1701 host x.x.x.x
pager lines 24
logging enable
logging asdm informational
mtu outside 1500
mtu Outside2 1500
mtu inside 1500
mtu Inside2 1500
mtu management 1500
icmp unreachable rate-limit 1 burst-size 1
asdm image disk0:/asdm-632.bin
no asdm history enable
arp timeout 14400
global (outside) 101 interface
nat (inside) 101 0.0.0.0 0.0.0.0
nat (Inside2) 102 0.0.0.0 0.0.0.0
nat (management) 101 0.0.0.0 0.0.0.0
access-group outside_access_in in interface outside
route outside 0.0.0.0 0.0.0.0 10.245.254.1 1
route inside 10.245.0.0 255.255.0.0 10.245.253.2 1
timeout xlate 3:00:00
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
dynamic-access-policy-record DfltAccessPolicy
aaa authentication ssh console LOCAL
http server enable
http 192.168.1.0 255.255.255.0 management
http 10.245.2.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
crypto ca trustpoint ASDM_TrustPoint0
enrollment terminal
subject-name CN=EASTON-DC-SR1-5510-1
crl configure
crypto isakmp policy 1
authentication pre-share
encryption 3des
hash sha
group 2
lifetime 86400
telnet timeout 5
ssh 10.245.0.0 255.255.0.0 inside
ssh timeout 30
console timeout 30
threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
webvpn
username sshuser1 password QeDXBFUts7/E3/zS encrypted privilege 15
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
  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 rsh
  inspect rtsp
  inspect esmtp
  inspect sqlnet
  inspect skinny
  inspect sunrpc
  inspect xdmcp
  inspect sip
  inspect netbios
  inspect tftp
  inspect ip-options
  inspect pptp
!
service-policy global_policy global
prompt hostname context
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:b543d816efdf990fb43b2bde4b8f167a
: end

27 Replies 27

Are you trying to establish an L2TP/IPsec connection to this ASA?

I don't see the configuration.

Please refer to this link for an example:

http://www.cisco.com/en/US/docs/security/asa/asa82/configuration/guide/l2tp_ips.html

Federico.

I am trying to establish it outbound from the LAN behind this ASA. The ASA seems to be blocking L2TP to another location from this one.

L2TP uses these ports:
User Datagram Protocol (UDP) 500, UDP 1701
ESP - Internet Protocol (IP) protocol 50

The ACL that you have inside should permit this but remove it and try again.
clear config access-list traffic

If the problem persists, add the ICMP inspection and try to PING the L2TP address you're trying to connect to:
policy-map global_policy
  class inspection_default
    inspect icmp

If there's connectivity, you can trace the connection with packet-tracer:
packet-tracer input inside udp x.x.x.x 1024 y.y.y.y 500

x.x.x.x will be the internal IP of the machine trying to connect and
y.y.y.y the L2TP public IP.

If the results are fine, can check the logs:
sh logs to see any possible message

We can start with this, let us know how it goes.

Federico.

Here is where I stand:

ASA Version 8.2(2)19
!
hostname ****************
domain-name cisco.com
enable password ds4hdW4uvMnfKnfo encrypted
passwd 2KFQnbNIdI.2KYOU encrypted
names
!
interface Ethernet0/0
nameif outside
security-level 0
ip address 10.245.254.2 255.255.255.0
!
interface Ethernet0/1
shutdown
nameif Outside2
security-level 100
no ip address
!
interface Ethernet0/2
nameif inside
security-level 100
ip address 10.245.253.1 255.255.255.0
!
interface Ethernet0/3
shutdown
nameif Inside2
security-level 100
no ip address
!
interface Management0/0
nameif management
security-level 100
ip address 10.245.1.2 255.255.255.0
management-only
!
boot system disk0:/asa822-19-k8.bin
ftp mode passive
dns server-group DefaultDNS
domain-name cisco.com
same-security-traffic permit inter-interface
access-list outside_access_in remark Access Rule to Allow ESP traffic
access-list outside_access_in remark Access Rule to allow ISAKMP to *****
access-list outside_access_in remark Access Rule to allow port 4500 (NAT-T) to ****
access-list outside_access_in remark Access Rule to allow port 1701 (L2TP) to ****
access-list outside_access_in extended permit esp any host x.x.x.x
access-list outside_access_in extended permit udp any eq isakmp host x.x.x.x
access-list outside_access_in extended permit udp any eq 4500 host x.x.x.x
access-list outside_access_in extended permit udp any eq 1701 host x.x.x.x
pager lines 24
logging enable
logging asdm informational
mtu outside 1500
mtu Outside2 1500
mtu inside 1500
mtu Inside2 1500
mtu management 1500
icmp unreachable rate-limit 1 burst-size 1
asdm image disk0:/asdm-632.bin
no asdm history enable
arp timeout 14400
global (outside) 101 interface
nat (inside) 101 0.0.0.0 0.0.0.0
nat (Inside2) 102 0.0.0.0 0.0.0.0
nat (management) 101 0.0.0.0 0.0.0.0
access-group outside_access_in in interface outside
route outside 0.0.0.0 0.0.0.0 10.245.254.1 1
route inside 10.245.0.0 255.255.0.0 10.245.253.2 1
timeout xlate 3:00:00
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
dynamic-access-policy-record DfltAccessPolicy
aaa authentication ssh console LOCAL
http server enable
http 192.168.1.0 255.255.255.0 management
http 10.245.2.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
crypto ca trustpoint ASDM_TrustPoint0
enrollment terminal
subject-name CN=EASTON-DC-SR1-5510-1
crl configure
crypto isakmp policy 1
authentication pre-share
encryption 3des
hash sha
group 2
lifetime 86400
telnet timeout 5
ssh 10.245.0.0 255.255.0.0 inside
ssh timeout 30
console timeout 30
threat-detection basic-threat
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
webvpn
username sshuser1 password QeDXBFUts7/E3/zS encrypted privilege 15
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
  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 rsh
  inspect rtsp
  inspect esmtp
  inspect sqlnet
  inspect skinny
  inspect sunrpc
  inspect xdmcp
  inspect sip
  inspect netbios
  inspect tftp
  inspect ip-options
  inspect pptp
!
service-policy global_policy global
prompt hostname context
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:b543d816efdf990fb43b2bde4b8f167a
: end

Still no luck

Did you try the suggestions?

Can you PING the actual address you're trying to VPN to? (from the local PC).

Federico.

It works if I connect to the network in front of the asa, but not behind it so I know it works. I can't ping it cause they have ICMP disabled on their end.

If it works in front of the ASA, then just need to check what's wrong with the ASA (obvious!! but that's good :-))

I don't see a need for this command:

static (inside,outside) interface 64.85.182.76 netmask 255.255.255.255

And also, what's the IP of the local PC that is trying to connect?

And what's the IP of the L2TP server? Or how do you try the connection?

Federico.

Well I want to do it so anyone can access it, do I have to put in an entry for every single PC? That would make sense but kind of not be what i'm looking for at the same time.

The IP of the L2TP server is that 64.x.x.x address specified.

I updated to where my config is now at in this point in time. See previous config post.

You don't need the command, please remove it.

Try the L2TP connection again to the 64.x.x.x address.

Check with

sh xlate local x.x.x.x

to see if the internal PC is getting out to the Internet properly (x.x.x.x will be the IP of the internal machine where you're initiaing the L2TP connection).

Federico.

I removed that static command. How can I get all the computers from this location to connect to the remote L2TP server without manually setting an ACL for each individual host?

You don't need an ACL at all.

This is because the L2TP connection is originated from a higher-security interface to a lower-security interface.

This traffic is already permitted by default.

The command I am asking you to remove is the static NAT command (where you have the 64.x.x.x) address.

That's not an ACL and is incorrect (and not needed).

Federico.

I know, like I said I removed it.

Without the ACLs it did not work. With the ACLs it does not work....so im stumped.

I kinda gave you some troubleshooting tools or commands to try that should let us know what the problem is.

Federico.

I rand the xlate command and got this:

46 in use, 173 most used

Any other tools you wanted me to run?

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