HowtoForge provides user-friendly Linux tutorials.
How do I find out who is logged in on my system?Author: admin • Tags: shell • Comments: 0
You can find out about logged in users either by running who (Sample output: server:~# who root pts/0 Nov 12 11:28 (192.168.0.202) ) or w which gives more detailed output: server:~# w 11:29:49 up 2:19, 1 user, load average: 0.02, 0.01, 0.00 USER TTY FROM [email protected] IDLE JCPU PCPU WHAT root pts/0 192.168.0.202 11:28 0.00s 0.08s 0.01s w
How do I find out which gateway a Linux system is currently using?Author: admin • Tags: networking • Comments: 6
Run route -nee The output will look like this: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface MSS Window irtt 192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 0 0 0 0.0.0.0 192.168.0.1 0.0.0.0 UG 0 0 0 eth0 0 0 0 0.0.0.0 192.168.0.1 0.0.0.0 UG 0 0 0 eth0 0 0 0 This means that the system with the IP address 192.168.0.100 is using 192.168.0.1 as gateway.
How do I find out if a remote system is still alive, if certain services are running, which processes are running, etc.?Author: admin • Tags: linux • Comments: 0
You can use ping to see if the system is alive: ping -c4 <system's IP address> To see if a certain service is still alive, use the telnet command: telnet <system's IP address> 25 (for SMTP) telnet <system's IP address> 80 (for HTTP) telnet <system's IP address> 110 (for POP3) You can login to the system using SSH (port 22) (use PuTTY if you are on a Windows PC; PuTTY is an SSH client for Windows), and when you are on the system, you have a few useful tools to gather more information:
Greylisting - fight Spam with Postgrey and Postfix on Debian and UbuntuAuthor: erk • Tags: antivirus, debian, postfix • Comments: 9
There are numerous ways to prevent spam from reaching your inbox, the most popular is probably SpamAssassin. Greylisting will not replace spam filtering software like SA but it will serve as a powerful first hurdle for spam thus reducing the ammount of spam entering the system at all.
Linux: How to burn a CD/DVD through the command lineAuthor: Bill Toulas • Tags: linux, shell • Comments: 0
Carrying out common daily tasks such as burning a DVD through the comfort of a user-friendly graphical interface is, of course, a good thing, but unfortunately things don't always work as expected. When this is the case, Linux users can revert to the good old terminal to get things done no matter what. On this quick tutorial, we will see how Linux users can utilize the terminal to burn audio CDs, data DVDs or ISO images on a disk.