02-15-2007 12:59 PM - edited 03-09-2019 05:24 PM
I'm having an issue with my VPN software connecting to a remote PIX. It had to go through my home PIX first.
I was told to use NAT-T and forward UDP 4500 but I don't know how to do either of these.
Can anyone help please? I've been trying to get this working for almost 2 weeks.
02-15-2007 01:09 PM
Add "isakmp nat-traversal" to pix. This will allow ipsec to function with pat. UDP 4500 is the port that ipsec over udp uses for udp encapsulation of esp packets.
02-15-2007 01:31 PM
Hi,
In the VPN client application, select the specific connection entry, modify it, goto transport tab and make sure 'Enable Transparent Tunneling' is checked and the 'IPSEC over UDP (NAT/PAT) is selected.
HTH,
Kamal
02-16-2007 06:55 AM
Great suggestions... I appreciate your responses however it still does not work.. unless I am missing something I think it would be better if I posted my config? Also maybe a step by step to configure it would help.
02-16-2007 06:58 AM
Yes, post your config, remove all sensitive information..passwords etc.
02-16-2007 03:22 PM
Building configuration...
: Saved
:
PIX Version 6.3(5)
interface ethernet0 auto
interface ethernet1 100full
nameif ethernet0 outside security0
nameif ethernet1 inside security100
enable password encrypted
passwd encrypted
hostname pixfirewall
domain-name ciscopix.com
clock timezone EST -5
clock summer-time EDT recurring
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 inside_access_in permit ip any any
pager lines 24
logging on
logging console informational
logging buffered informational
icmp deny any outside
mtu outside 1500
mtu inside 4000
ip address outside dhcp setroute retry 4
ip address inside 192.168.1.1 255.255.255.0
ip verify reverse-path interface outside
ip audit info action alarm
ip audit attack action alarm
pdm location 192.168.1.0 255.255.255.255 inside
pdm location 0.0.0.0 255.0.0.0 outside
pdm location 0.0.0.0 255.255.255.255 outside
pdm location 68.66.174.196 255.255.255.255 outside
pdm logging informational 200
pdm history enable
arp timeout 14400
global (outside) 10 interface
nat (inside) 10 0.0.0.0 0.0.0.0 0 0
access-group inside_access_in in interface inside
rip inside passive version 2
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
http server enable
http 0.0.0.0 0.0.0.0 outside
http 192.168.1.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
sysopt connection permit-ipsec
sysopt connection permit-pptp
sysopt connection permit-l2tp
crypto ipsec transform-set ESP-AES-256-SHA esp-aes-256 esp-sha-hmac
isakmp enable outside
isakmp enable inside
isakmp identity address
isakmp nat-traversal 20
telnet timeout 5
ssh 192.168.1.0 255.255.255.255 inside
ssh timeout 5
console timeout 0
dhcpd address 192.168.1.100-192.168.1.199 inside
dhcpd lease 3600
dhcpd ping_timeout 750
dhcpd auto_config outside
dhcpd enable inside
username password
encrypted privilege 15
terminal width 80
Cryptochecksum:
: end
[OK]
02-16-2007 03:41 PM
Hi,
Please try this :
access-list outside_in permit udp any any eq 500
access-list outside_in permit udp any any eq 4500
access-group outside_in in interface outside
You can replace the source 'any' with the remote peer's public IP address.
HTH,
Regards,
Kamal
02-16-2007 04:04 PM
Is there a command that i can use to send that to the PIX? I tried sending that and it didn't change anything in the access list.
02-16-2007 04:26 PM
Hi Marc,
These are three different commands :
access-list outside_in permit udp any any eq 500
access-list outside_in permit udp any any eq 4500
access-group outside_in in interface outside
Please login to the PIX using telnet or SSH and paste these commands. If you access using PDM then goto 'Tools' and 'Command Line Interface' and the paste one command at a time.
It should work.
Regards,
Kamal
02-16-2007 05:17 PM
It still wont let me browse the remote network. Just to clarify... I disconnected the PIX today and went right through the cable modem.. no firewall and everything worked.
02-16-2007 06:03 PM
I reset the PIX to factory defaults and reinputted those commands. Still wont let me browse the network or use remote desktop
Building configuration...
: Saved
:
PIX Version 6.3(5)
interface ethernet0 auto
interface ethernet1 auto
nameif ethernet0 outside security0
nameif ethernet1 inside security100
enable password xxx
passwd xxx
hostname pixfirewall
domain-name ciscopix.com
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 outside_in permit udp any any eq isakmp
access-list outside_in permit udp any any eq 4500
pager lines 24
mtu outside 1500
mtu inside 1500
ip address outside dhcp setroute
ip address inside 192.168.1.1 255.255.255.0
ip audit info action alarm
ip audit attack action alarm
pdm logging informational 100
pdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside) 1 0.0.0.0 0.0.0.0 0 0
access-group outside_in in interface outside
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
http server enable
http 192.168.1.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
snmp-server community public
no snmp-server enable traps
floodguard enable
sysopt connection permit-ipsec
sysopt connection permit-pptp
sysopt connection permit-l2tp
isakmp nat-traversal 20
telnet timeout 5
ssh timeout 5
console timeout 0
dhcpd address 192.168.1.2-192.168.1.254 inside
dhcpd lease 3600
dhcpd ping_timeout 750
dhcpd auto_config outside
dhcpd enable inside
terminal width 80
Cryptochecksum:xxx
: end
[OK]
02-16-2007 06:38 PM
I'm getting this error in my logs..
3 Feb 17 2007 02:30:24 305006: portmap tranlation cration failed for protocol 50 src inside: *My computer* dst outside: *Remote Site*
02-16-2007 06:45 PM
After a quick search I found that these three commands needed to be run:
fixup protocol esp-ike
access-list outside_access_in permit esp any any
access-group outside_access_in in interface outside
Apparently... the PIX was blocking protol 50 which is the ESP/encapsulating protocol for IPsec? Oh well either way it works. Thank you all for your help.. someone should write an article about this.
02-19-2007 06:36 AM
It should not be that way.
Going back to the original problem, what pix are we dealing with, local or remote?
You need to add "isakmp nat-traversal" to remote pix.
As it is now, you are not running nat-t and will not be able to establish more than 1 vpn session.
02-20-2007 08:03 AM
The problem has nothing to do with the remote PIX. The local PIX was blocking the VPN connections.
Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: