Solved

PIX FTP Fixup

Posted on 2004-09-10
3
1,099 Views
Last Modified: 2013-11-29
I'm trying to allow a client behind the firewall to upload (STOR) files in active mode to a server across the internet.  I am using NAT and have configured the ftp fixup with and without the strict option and so far the remote ftp server has been unable to open a data connection to my client.

After enabling auditing I can see that the server is attempting to open a socket to my client on the port number listed in the PORT command but the PIX is denying the connection due to the access list attached to the outside interface.  My understanding of the fixup command was that the PIX would open a temporary hole in the firewall so the existing access-list rules would not apply.  Anyways, it appears that the fixup command is correctly NAT'ing the internal IP address listed in the PORT command since I'm getting a connection request back, but it's not opening up a hole for the data port.

My customer's server is behind it's own firewall,  I've tried using passive mode but whatever their firewall is, it's not letting me open an inboud data connection either.  So I'd rather stay in active mode and fix the problem on my side.

Any thoughts?
0
Comment
Question by:dcrysler
  • 2
3 Comments
 
LVL 79

Accepted Solution

by:
lrmoore earned 500 total points
ID: 12029130
You can try explicitly permitting the high ports from that server inbound in your inbound access-list, just as a temporary measure..

access-list outside_in permit tcp host <server> host <PIX IP> gt 1024

But, you are correct that the fixup "should" allow your client to work in active mode.

It may still be an issue with your customer's firewall not permitting outbound > 1024 for ftp ....
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 12029154
Sorry, I got the passive and active backwards...

Disregard the access-list entry..

Perhaps port 20 is not open on the other firewall?

Have you tried disabling fixup ftp and using passive mode?
0
 
LVL 1

Author Comment

by:dcrysler
ID: 12029489
Never mind, it looks like I'll have to use passive mode. I did try it without success,  but the error ended up being on my customers side.  Their ftp server is multi-homed with the ftp server listening on a secondary address.  When their server tries to open the data connection it uses it's primary ip address causing PIX to reject it.

0

Featured Post

Windows Server 2016: All you need to know

Learn about Hyper-V features that increase functionality and usability of Microsoft Windows Server 2016. Also, throughout this eBook, you’ll find some basic PowerShell examples that will help you leverage the scripts in your environments!

Join & Write a Comment

Even if you have implemented a Mobile Device Management solution company wide, it is a good idea to make sure you are taking into account all of the major risks to your electronic protected health information (ePHI).
Meet the world's only “Transparent Cloud™” from Superb Internet Corporation. Now, you can experience firsthand a cloud platform that consistently outperforms Amazon Web Services (AWS), IBM’s Softlayer, and Microsoft’s Azure when it comes to CPU and …
Viewers will learn how to properly install and use Secure Shell (SSH) to work on projects or homework remotely. Download Secure Shell: Follow basic installation instructions: Open Secure Shell and use "Quick Connect" to enter credentials includi…
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…

708 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

12 Experts available now in Live!

Get 1:1 Help Now