1. Home
  2. Cisco Systems
  3. VPN client will not connect behind firewall

VPN client will not connect behind firewall

I just setup my first PIX 501. I updated it to 6.3(5) and PDM 3.0(4). I used the VPN wizard to make a client VPN, and it works perfectly when my PC is connected directly to the internet (has a public IP). When I'm behind a firewall, the VPN connects, but I cannot ping or connect to any services behind the pix. And ideas?

: Saved : Written by enable_15 at 10:12:23.732 UTC Fri Aug 4 2006 PIX Version 6.3(5) interface ethernet0 auto interface ethernet1 100full nameif ethernet0 outside security0 nameif ethernet1 inside security100 fixup protocol dns maximum-length 512 fixup protocol ftp 21 fixup protocol h323 h225 1720 fixup protocol h323 ras 1718-1719 fixup protocol http 80 fixup protocol rsh 514 fixup protocol rtsp 554 fixup protocol sip 5060 fixup protocol sip udp 5060 fixup protocol skinny 2000 fixup protocol smtp 25 fixup protocol sqlnet 1521 fixup protocol tftp 69 names access-list joby_splitTunnelAcl permit ip 10.10.11.0 255.255.255.0 any access-list inside_outbound_nat0_acl permit ip 10.10.11.0 255.255.255.0

10.10.11.192 255.255.255.192 access-list outside_cryptomap_dyn_20 permit ip any 10.10.11.192 255.255.255.192 pager lines 24 mtu outside 1500 mtu inside 1500 ip address outside 70.x.x.x 255.255.255.248 ip address inside 10.10.11.2 255.255.255.0 ip audit info action alarm ip audit attack action alarm ip local pool REAL_VPN_IP_POOL 10.10.11.210-10.10.11.229 pdm logging informational 100 pdm history enable arp timeout 14400 global (outside) 1 interface nat (inside) 0 access-list inside_outbound_nat0_acl nat (inside) 1 0.0.0.0 0.0.0.0 0 0 route outside 0.0.0.0 0.0.0.0 70.x.x.x 1 timeout xlate 0:05:00 timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 rpc 0:10:00 h225 1:00:00 timeout h323 0:05:00 mgcp 0:05:00 sip 0:30:00 sip_media 0:02:00 timeout sip-disconnect 0:02:00 sip-invite 0:03:00 timeout uauth 0:05:00 absolute aaa-server TACACS+ protocol tacacs+ aaa-server TACACS+ max-failed-attempts 3 aaa-server TACACS+ deadtime 10 aaa-server RADIUS protocol radius aaa-server RADIUS max-failed-attempts 3 aaa-server RADIUS deadtime 10 aaa-server LOCAL protocol local no snmp-server location no snmp-server contact snmp-server community public no snmp-server enable traps floodguard enable sysopt connection permit-ipsec crypto ipsec transform-set ESP-3DES-MD5 esp-3des esp-md5-hmac crypto dynamic-map outside_dyn_map 20 match address outside_cryptomap_dyn_20 crypto dynamic-map outside_dyn_map 20 set transform-set ESP-3DES-MD5 crypto map outside_map 65535 ipsec-isakmp dynamic outside_dyn_map crypto map outside_map interface outside isakmp enable outside isakmp nat-traversal 20 isakmp policy 20 authentication pre-share isakmp policy 20 encryption 3des isakmp policy 20 hash md5 isakmp policy 20 group 2 isakmp policy 20 lifetime 86400 vpngroup xxxx address-pool REAL_VPN_IP_POOL vpngroup xxxx dns-server 10.10.11.10 10.10.11.11 vpngroup xxxx default-domain joby.local vpngroup xxxx split-tunnel joby_splitTunnelAcl vpngroup xxxx idle-time 1800 vpngroup xxxx password

Thanks for your help!

-LB

Reply to
lbenes
Loading thread data ...

When Cisco VPN client tries to connect to a PIX it starts with IKE (UDP port 500). If there is no NAT then it tries the protocol specified in PIX (in your case that's ESP). If NAT is detected it switches to NAT-Traversal mode which means UDP port 4500. Does the firewall you are behind allow UDP/4500?

Reply to
Jyri Korhonen

My firewall does not have any special rules to forward port 4500. It does have the option to allow IPSec pass through enabled. Should I change the ipsec transform set? To what?

thanks

-LB Jyri Korh>

Reply to
lbenes

The other transport protocol you can select in PIX is AH and that will not survive any kind of NAT. Protocol ESP will work if you have basic 1-to-1 NAT, but not with many-to-1 NAT (aka PAT, NAPT etc.). So I don't think that you can gain anything by changing the transform set.

Reply to
Jyri Korhonen

I think that if the PIX uses AH the tunel should not get established (after a device doing NAT)

Alex.

Reply to
AM

If I use the VPN wizard and create a private IP pool, say

172.16.200.1-20, then the VPN group that it creates does not work under any c> I just setup my first PIX 501. I updated it to 6.3(5) and PDM 3.0(4). I
Reply to
lbenes

The Phase 1 tunnel will be established, because Phase 1 does not use AH. The security associations for the Phase 2 tunnel will also get more than half established, because AH is not required to exchange the SA information. The tunnel would, though, be unable to pass any traffic, and might not finish Phase 2.

Reply to
Walter Roberson

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.