VPN Client Connect to PIX FW but cannot browse internal network..

Dec 16, 2006 3 Replies
VPN Client Connect to PIX FW but cannot browse internal network.. open original image

Having a problem connecting to any internal servers once I establish a VPN connection through the PIX 506e firewall. I was trying to use IAS server instead of creating a bunch of vpngroups.



Diagram:



Internet | | Router | | Firewall | | Internal Network (IAS is on the internal network)


Please see below's config. I know it's a routing issue but cannot figure it out. Any information is appreciated. Thanks!


PIX# sho run



access-list 103 permit ip 192.168.16.0 255.255.255.0 10.1.2.0



255.255.255.0

ip local pool ippool 10.XX.XX.XXX-10.XX.XX.XXX



global (outside) 1 interface



nat (inside) 0 access-list 103 nat (inside) 1 0.0.0.0 0.0.0.0 0 0



access-group 101 in interface outside



route outside 0.0.0.0 0.0.0.0 66.251.40.201 1



aaa-server radius-server protocol radius aaa-server radius-server (inside) host 172.26.1.8 cisco123 timeout 10



sysopt connection permit-ipsec



crypto ipsec transform-set testset esp-3des esp-md5-hmac crypto dynamic-map testmap 10 set transform-set testset crypto map testconn 10 ipsec-isakmp dynamic testmap crypto map testconn client authentication radius-server crypto map testconn interface outside



isakmp enable outside isakmp identity address isakmp policy 10 authentication pre-share isakmp policy 10 encryption 3des isakmp policy 10 hash md5 isakmp policy 10 group 2 isakmp policy 10 lifetime 86400



vpngroup testias address-pool ippool vpngroup testias dns-server DNS1 DNS2 vpngroup testias wins-server WINS1 vpngroup testias default-domain DOMAIN1 vpngroup testias idle-time 1800 vpngroup testias password



Thanks so much Brian!! You are the man!!

What does this command do:

"isakmp nat-traversal 20 "

Please explain this to me.

Brian V wrote:

In short, it allows a device that is behind a NAT/PAT IP address to pass traffic thru the firewall.

The official Cisco answer: isakmp nat-traversal

Network Address Translation (NAT), including Port Address Translation (PAT), is used in many networks where IPSec is also used, but there are a number of incompatibilities that prevent IPSec packets from successfully traversing NAT devices. NAT traversal enables ESP packets to pass through one or more NAT devices.

The firewall supports NAT traversal as described by Version 2 and Version 3 of the IETF "UDP Encapsulation of IPsec Packets" draft, available at

formatting link
and NAT traversal is supported for both dynamic and static crypto maps. NAT traversal is disabled by default on the firewall.

To enable NAT traversal, check that ISAKMP is enabled (you can enable it with the isakmp enable if_name command) and then use the isakmp nat-traversal [natkeepalive] command. (This command appears in the configuration if both ISAKMP is enabled and NAT traversal is enabled.) If you have enabled NAT traversal, you can disable it with the no isakmp nat-traversal command. Valid values for natkeepalive are from 10 to 3600 seconds. The default is 20 seconds.

If needed, the show isakmp sa detail command assists in debugging NAT traversal.

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