Improve company productivity with a Business Account.Sign Up

x
?
Solved

PIX FTP Fixup

Posted on 2004-09-10
3
Medium Priority
?
1,143 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 1500 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

The 14th Annual Expert Award Winners

The results are in! Meet the top members of our 2017 Expert Awards. Congratulations to all who qualified!

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Just after setting up Cloud PBX connectivity and migrated Skype users to SFBO, we noticed inbound calls not working but outbound calls would work.
This article is about building a site to site VPN tunnels in Cisco CSR1000V router with IOS XE. There are two Policy Based IPsec VPN tunnels configured on CSR1000V router one with NAT and another without NAT.
As a trusted technology advisor to your customers you are likely getting the daily question of, ‘should I put this in the cloud?’ As customer demands for cloud services increases, companies will see a shift from traditional buying patterns to new…
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…

595 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