Port Monitoring

[roadsweeper]

Hi all

I'm trying to set up a file sharing application on my home PC but am struggling with firewall configuration since I have two hardware firewalls between my computer and the web.

What I'd like is some kind of tool that allows me to test which of the firewalls is blocking traffic on a particular port - can anyone recommend anything?

Thanks in advance.

roadie.

[JamieBeeston]

nmap will portscan the IP in questin and return if its open, filtered or down.

google for it.

[guydw]

two hardware firewalls ? at home ? why ?

use nmap, but it shouldn't be hard to set up going through two fw's, what is your setup ?

[guydw]

oh isee, you're saying that you don't have administrative access to these firewalls ?

[cuneus]

www.sysinternals.com/ntw2k/source/tcpview.shtml

[roadsweeper]

guydw said:

oh isee, you're saying that you don't have administrative access to these firewalls ?

I do, but having opened the ports my app is still not working, so I'm guessing I've missed something somewhere!

[roadsweeper]

guydw said:

two hardware firewalls ? at home ? why ? use nmap, but it shouldn't be hard to set up going through two fw's, what is your setup ?

I'm building a fairly complex home network which includes a RAID5 server distributing multimedia content around my home. I am hard-wiring CAT5 access points around the home that are serverd by the server and a switch. I also have a wireless nework, VoIP, colour laser printer, etc. Combined together I end up with what is a simple corporate network but a complex home one!

[malman]

Set the firewalls to log blocked connections both in and outbound. This will show which ports you may have missed. Obviously everything that hits the ouside of the firewall is not valid but you can check it out against a list of known ports for your app

For further network analysis look at ethereal. Its a free network monitor for linux and windows platfoms. It can show you exactly whats going on on your network.

HTH

Neil

[roadsweeper]

malman said:

Set the firewalls to log blocked connections both in and outbound. This will show which ports you may have missed. Obviously everything that hits the ouside of the firewall is not valid but you can check it out against a list of known ports for your app For further network analysis look at ethereal. Its a free network monitor for linux and windows platfoms. It can show you exactly whats going on on your network. HTH Neil

Hi Neil

I have got the system working now, but I will check out ethereal as I'm interested in any tools that can help with this kind of thing.

Thanks.

roadie.