Solved

Linux Port Checking

Posted on 2006-06-20
4
1,129 Views
Last Modified: 2010-05-18
Hi,

On Red Hat Linux, how do I know is a port is using by programs?

I simply want to check is port 3300 open or avaiable to use.

thanks,

Jack

0
Comment
Question by:huabin
4 Comments
 
LVL 10

Accepted Solution

by:
Luxana earned 200 total points
ID: 16948635
Hi,

One such a tool is nmap

Example:

#nmap localhost

Starting nmap 3.81 ( http://www.insecure.org/nmap/ ) at 2006-06-21 15:19 EST
Interesting ports on localhost.localdomain (127.0.0.1):
(The 1653 ports scanned but not shown below are in state: closed)
PORT     STATE SERVICE
22/tcp   open  ssh
25/tcp   open  smtp
111/tcp  open  rpcbind
113/tcp  open  auth
443/tcp  open  https
614/tcp  open  unknown
631/tcp  open  ipp
1016/tcp open  unknown
3306/tcp open  mysql
5432/tcp open  postgres

Nmap finished: 1 IP address (1 host up) scanned in 0.474 seconds
0
 
LVL 16

Assisted Solution

by:Blaz
Blaz earned 100 total points
ID: 16948662
netstat -ln | grep :3300
0
 
LVL 2

Assisted Solution

by:fpintos
fpintos earned 100 total points
ID: 16949340
You can also use

lsof -i :3300

to list all processes that are using port 3300
0
 
LVL 3

Assisted Solution

by:Ustas
Ustas earned 100 total points
ID: 16950149
Try

netstat -napt

for all tcp ports and processes using them (in your case: netstat -napt | grep -w 3300)

or

netstat -napu

for all udp ports and their respective processes.
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

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

Suggested Solutions

Title # Comments Views Activity
Reaching outside NTP servers from within a domain? 12 113
E-mail settings for Fail2ban 7 151
Computers missing from Windows Explorer Networks 10 153
ifconfig 4 90
I have seen several blogs and forum entries elsewhere state that because NTFS volumes do not support linux ownership or permissions, they cannot be used for anonymous ftp upload through the vsftpd program.   IT can be done and here's how to get i…
Note: for this to work properly you need to use a Cross-Over network cable. 1. Connect both servers S1 and S2 on the second network slots respectively. Note that you can use the 1st slots but usually these would be occupied by the Service Provide…
Nobody understands Phishing better than an anti-spam company. That’s why we are providing Phishing Awareness Training to our customers. According to a report by Verizon, only 3% of targeted users report malicious emails to management. With compan…
Finds all prime numbers in a range requested and places them in a public primes() array. I've demostrated a template size of 30 (2 * 3 * 5) but larger templates can be built such 210  (2 * 3 * 5 * 7) or 2310  (2 * 3 * 5 * 7 * 11). The larger templa…

680 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