[thelist] FTP, IP Filtering, and Firewalls

[Joshua Olson]

List,

I'm configuration FTP on a server and I want to maximally lock down the
ports.  I opened the normal ports for FTP, 20 and 21, and found that this
works very well so long as the client is not behind a firewall and was
therefore able to use Active Mode FTP transfer.  But, if they are behind a
firewall, am I correct in assuming that they MUST be able to use Passive
Mode, which means that the server needs to have some ports open in the upper
range?  If so, is there an easy way to configure the open ports using the IP
Filtering OTHER than enumerate each possible port one at a time?

Thanks in advance.

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Joshua Olson
Web Application Engineer
WAE Tech Inc.
http://www.waetech.com/service_areas/
706.210.0168