Go Premium for a chance to win a PS4. Enter to Win

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 355
  • Last Modified:

FTP Service on IIS 6.0 will only work on Primary IP on NIC

I have a problem that is baking my noodle. We have a Win 2003 Server running IIS 6.0. We have five different FTP sites configured, each using a separate IP address (we have hundreds of IPs bound to the NIC, as this server hosts numerous client websites).

The FTP Service was configured to use Passive FTP on ports 5000-5010, and Windows Firewall exceptions added for all relevant ports. The server ran for years without any trouble, servicig all traffic both http and ftp.

Beginning today, for no apparent reason that can be found as yet, the FTP service began dropping connections, due to those connections being denied by the Windows Firewall.

So far what I have done is reset the PassivePortRange in the IIS metabase (now set to 5500-5700 just to ensure we have enough available ports), and created exceptions in the windows firewall for all those same ports (5500-5700), as well as ensured that exceptions exist for port 21.

NOW, the problem is this:

The server is allowing ftp connections to just one ftp site - that site that uses the NIC's primary IP (let's call it 75.85.95.100 just for illustration).

Incoming ftp connections for the other four ftp sites - those sites that use IPs other than the primary one - are refused.

So, for example:

ftp.site1.com - resolves to 75.85.95.100 - connects fine
ftp.site2.com - resolves to 75.85.95.101 - firewall denies connection
ftp.site3.com - resolves to 75.85.95.102 - firewall denies connection
etc.

When I turn off the windows firewall all ftp sites work perfectly. When turned back on only ftp site #1 works.

What am I missing here?
0
worthyking1
Asked:
worthyking1
  • 2
1 Solution
 
eeRootCommented:
can you post a few screen shots of the FTP server config and firewall config, (with confidential info blurred out) and the results of the commands "netsh advfirewall show allprofiles" and "netstat -ano"
0
 
worthyking1Author Commented:
System fixed itself. With no changes whatsoever it began working normally today. Turned on the firewall and all ftp sites are working just fine.  I can only guess that Win 2003 has some sort of delay between setting the PassivePortRange and when it actually starts using those ports.

@eeRoot There is nothing wrong with my ftp or firewall config so I'm not going to take the time to make screenshots of those. Also, the netsh advfirewall command is not available on Win 2003.
0
 
worthyking1Author Commented:
See comments.
0

Featured Post

NFR key for Veeam Agent for Linux

Veeam is happy to provide a free NFR license for one year.  It allows for the non‑production use and valid for five workstations and two servers. Veeam Agent for Linux is a simple backup tool for your Linux installations, both on‑premises and in the public cloud.

  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now