Checking for open ports

[asc]

Hello!

I have two questions regarding open ports:
(1) How can I check which ports are open on my machine?
(2) Are there any log-files that log connections to open ports?

[Quella]

typing 'netstat -an' will show you the listening and open ports. I would be more concerned with ports listening on 0.0.0.0 (all interfaces) than those on 127.0.0.1 (localhost). Here you will see all open and listening ports from the box.

Quella

[ghaefb]

Nmap is a great tool for this.
Run in terminal: nmap -sS -v -p- 127.0.0.1

If you have FedoraCore3 you can use NetworkTools -> Port scan. Use 127.0.0.1

[moronbros]

I use:


netstat -tuapen | grep LISTEN


That's a pretty granular way of getting what you want. I think I found that on another thread here..just search more before you post =P

[pigpen]

Also try[root@pc50511 root]# lsof -i

[sej7278]

Buy a $30 router. All you ports are now closed to the outside world, yay!

[Jman]

There are a variety of port scanners on the web that scan common ports.

One of these is the security risks checker from Symantec (http://securityresponse.symantec.com/).

[asc]

Hello,

Thank's for all the answers!

@Jman
The security checker from Symantec seems to work only for Windows systems.

[Tashiro]

Also check the securtiy site www.grc.com

And do the Shields up test (http://www.grc.com/default.htm).

Tashiro