Solved

How to tell what ports are being used so that I can avoid our Cisco Firewall blocking them?

Posted on 2008-09-30
3
1,133 Views
Last Modified: 2013-11-16
We are going to put our servers behind a cisco ASA firewall and I would like to know whats the easiest way of finding out which ports are currently being used on our Windows 2003 machines. In theory I can research online to see each software that we run what port it uses (and close everything else), but in practice this will definitely mean we will "forget" some ports and so our applications/services will not work.

Other than the standard and well known port 80, 21 and so on so forth, is there an application I can use to show me which ports are currently being used?
0
Comment
Question by:leontas
3 Comments
 
LVL 11

Accepted Solution

by:
Bertling earned 80 total points
ID: 22605263
if you are moving all your servers to a DMZ you and you want to permit all required packets from the end users to the servers these are the ports i can think of:

RPC: 135
DNS: 53
LDAP: 389
Gloal catalog searches: 3268
SMTP: 25
HTTP/s: 80 & 443
Netbios: 139
SMB: 445
if you have databases: 1433
FTP: 21

you can also run netstat on all your servers you want to move to see what ports they have sessions with to particualr nodes or servers.
0
 
LVL 8

Assisted Solution

by:Jay_Gridley
Jay_Gridley earned 45 total points
ID: 22667244
You could also try installing a trial version of PRTG traffic grapher to get a history of a few days of the traffic going to your server. The trial is obviously free and should be long enough for you to get insight in  what traffic your server passes.

Download it from: http://www.paessler.com/prtg/
0
 
LVL 2

Author Comment

by:leontas
ID: 22667433
Thanks Jay, I'll try that too!
I have been away for the past few days so I haven't had the chance to also thank Bertling for his suggestion as well!
Will try the software and get back with info!
0

Featured Post

Free Tool: Subnet Calculator

The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Sonicwall will not export settings 4 98
Sonicwall blocks a site 49 91
Draytek (Site to Site VPN using IPSec) 6 38
Raising Forest Functional Level 9 34
We sought a budget ($5,000) firewall solution that would provide all the performance we needed with no single point of failure.  Hosting a SAAS web application in our datacenter, it was critical that we find a way to keep connectivity up and inbound…
While rebooting windows server 2003 server , it's showing "active directory rebuilding indices please wait" at startup. It took a little while for this process to complete and once we logged on not all the services were started so another reboot is …
I've attached the XLSM Excel spreadsheet I used in the video and also text files containing the macros used below. https://filedb.experts-exchange.com/incoming/2017/03_w12/1151775/Permutations.txt https://filedb.experts-exchange.com/incoming/201…

839 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