topic Re: ftp on alternate port in Network Security

ftp on alternate port

dlove — Mon, 11 Mar 2019 16:52:54 GMT

I can't get through the firewall on port 5052. I'm using firezilla and it says that it does not recognize an unroutable address. it works over the vpn so it's something to do with the asa.

Re: ftp on alternate port

Jerry Ye — Wed, 30 Dec 2009 23:20:29 GMT

Do you have firewall rules opened for this port?

Regards,

jerry

Re: ftp on alternate port

dlove — Thu, 31 Dec 2009 00:02:20 GMT

Yes. A static and an access list.

Re: ftp on alternate port

Jerry Ye — Thu, 31 Dec 2009 02:16:11 GMT

Assuming static means static NAT. With limited information, I can only suggest two things.

1) Make sure all routing is correct when access through the firewall. Verify it with ping and traceroute

2) Remove FTP inspection (fixup) and re-test

Regards,

jerry

Re: ftp on alternate port

dlove — Thu, 31 Dec 2009 02:32:41 GMT

This is all I have right now. I tried removing inspect with no luck.

access-list incoming extended permit tcp any host 68.216.158.101 eq 5052
static (inside,outside) tcp 68.216.158.101 5052 192.168.1.171 5052 netmask 255.255.255.255

Re: ftp on alternate port

Jerry Ye — Thu, 31 Dec 2009 04:02:31 GMT

Have you check your routing? (Not VPN)

You can also try to put a deny ip any any log at the end of the incoming ACL and send all the log to a syslog server to inspect what else is being blocked.

Regards,

jerry

Re: ftp on alternate port

vilaxmi — Fri, 01 Jan 2010 21:01:05 GMT

Hello,

If you wish to pass FTP traffic through your Firewall on NON STANDARD ports, then in order to make it work, please add the following MPF (modular Policy Framework) :-

Lets assume you have FTP server (1.1.1.1) on outside of your ASA , and you have clients in inside which needs to access the server. First of all, remove inspect ftp from global_policy and the proceed as follows for non std FTP inspection.

access-list FTP extended permit tcp any host 1.1.1.1 range 20 21

access-list FTP extended permit tcp host 1.1.1.1 any range 20 21

class-map class_ftp

match access-list FTP

Policy-map global_policy

class class_ftp

inspect ftp

service-policy global_policy global

HTH

Vijaya