Solved

PIX WAN Interface access by FQDN

Posted on 2006-06-15
22
482 Views
Last Modified: 2008-03-10
I am not able to access www.mydomain.com which points to the public ip assigned to the WAN interface of the PIX from inside the network.  How can i resolve this?
0
Comment
Question by:andreacadia
  • 10
  • 9
22 Comments
 
LVL 79

Expert Comment

by:lrmoore
ID: 16912436
You can't.
Assuming that you have a static nat mapping port 80 from the outside interface to an inside host, you have no choice except to resolve www.mydomain.com interanally to the private IP address.

Unless - your DNS server is located outside the pix and the dns request for www.mydomain.com passes through the firewall, then you can use "alias" or dns fixup.

static (inside,outside) tcp interface http 192.168.111.222 http dns netmask 255.255.255.255
                                                                                           ^^^

0
 

Author Comment

by:andreacadia
ID: 16912474
Correction, mydomain.com points to an IP that has a one to one translation configured on the PIX, not the IP asssigned to the PIX WAN. The ip is static natted back to my webserver...
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 16912512
Doesn't matter. Same issue.
0
 

Author Comment

by:andreacadia
ID: 16912553
Can you clarify everything after "unless"
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 16913305
What do your internal hosts use for their DNS server? Is it an internal server, or public server?
If it is internal, then you should resolve to the private IP address.
If it is an external dns server, the PIX will intercept the dns request and "doctor" the response to the real private IP address. This is done with "alias" command on previous versions, but with the "dns" keyword in the static xlate for the latest versions of PIX OS.
0
 

Author Comment

by:andreacadia
ID: 16913344
so in your example above the "192.168.111.222" is internal hos that my static nat points to?  Also, would this require an accompany access list statement?

how would the static nat look if it was applied to an available ip and not the WAN interface IP?
0
 

Author Comment

by:andreacadia
ID: 16913364
sorry, my hosts use dns servers provided by the ISP.
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 16913425
then try using the "dns" in the static as I demonstrated above
0
 
LVL 79

Accepted Solution

by:
lrmoore earned 500 total points
ID: 16914357
static (inside,outside) tcp <external ip> http <internal ip> http dns netmask 255.255.255.255
access-list outside_in permit tcp any host <external ip> eq http
access-group outside_in in interface outside
0
 

Author Comment

by:andreacadia
ID: 16952825
my existing static looks like this:

static (inside, outside) <public_ip> <private_ip> net mask 255.255.255.255 0 0
access-list in permit ip any host <public_ip>

where <public_ip> is not the IP assigned to PIX outside interface.

based on your last comment i should edit my config to look like this?:

static (inside, outside) <public_ip> <private_ip> DNS net mask 255.255.255.255 0 0


0
PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

 
LVL 79

Expert Comment

by:lrmoore
ID: 16952878
Exactly..
except that "nat mask" is one word "netmask", and I think that "DNS" needs to be lowercase "dns"
0
 

Author Comment

by:andreacadia
ID: 16953192
ok, i was just capitalzing "DNS" for emphasis..i will try this and let you know the result.
Thanks.
0
 

Author Comment

by:andreacadia
ID: 16955196
the change above did not seem to have any effect..
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 16955212
Where is the DNS server physically in relation to the PIX FW?
Inside, or outside?
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 16955218
Oh... did you flushdns from your client? It might have been in cache?
C:\>ipconfig/flushdns
0
 

Author Comment

by:andreacadia
ID: 16956419
for most of the network the DNS servers are outside of the PIX as they use the ISP's DNS server.  There is an additional subnet behind the PIX (one hop from the PIX lan network) whose gateway gets Natted to the additional Public IP of the PIX. On this additional subnet, a windows domain exists with a single domain controller that is also a dns server.
0
 

Author Comment

by:andreacadia
ID: 16956473
i tried flushing the dns cache to no avail.
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 16956915
What version PIX OS?
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 17144240
Question asked was answered -
"you can't" is a perfectly acceptible answer.
0
 
LVL 51

Expert Comment

by:Keith Alabaster
ID: 17146582
Point taken and thanks for highlighting it. My error in not realising that the rest of thread was secondary.

Thanks
Keith
0

Featured Post

Efficient way to get backups off site to Azure

This user guide provides instructions on how to deploy and configure both a StoneFly Scale Out NAS Enterprise Cloud Drive virtual machine and Veeam Cloud Connect in the Microsoft Azure Cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Overview The Cisco PIX 501, PIX 506e, ASA 5505 and ASA 5510 (most if not all of this information will be relevant to the PIX 515e but I do not have a working configuration handy to verify the validity) are primarily used within small to medium busi…
Have you experienced traffic destined through a Cisco ASA firewall disappears and you do not know if the traffic stops in the firewall or somewhere else? The solution is the capture feature. This feature was released in 6.2(1) and works in all firew…
Here's a very brief overview of the methods PRTG Network Monitor (https://www.paessler.com/prtg) offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…
A company’s greatest vulnerability is their email. CEO fraud, ransomware and spear phishing attacks are the no1 threat to a company’s security. Cybercrime is responsible for the largest loss of money to companies today with losses projected to r…

932 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now