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Cisco 350 Series And Kismet

Cisco 350 Series And Kismet

This tutorial is describing how to configure a Cisco Aironet wireless card and how to set up kismet in order to run with it.

Step-By-Step Configuration of NAT with iptables

Step-By-Step Configuration of NAT with iptables

This tutorial shows how to set up network-address-translation (NAT) on a Linux system with iptables rules so that the system can act as a gateway and provide internet access to multiple hosts on a local network using a single public IP address. This is achieved by rewriting the source and/or destination addresses of IP packets as they pass through the NAT system.

How do I start the X server in Suse 9.2 when the graphic card is working work in text mode?

To start the X server from a text mode session, execute the command:


How do I find out if a remote system is still alive, if certain services are running, which processes are running, etc.?

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:

How do I scan my Linux system for rootkits, worms, trojans, etc.?

Either with chkrootkit or with rkhunter.


Either install the package that comes with your distribution (on Debian you would run

apt-get install chkrootkit

), or download the sources from and install manually:

wget --passive-ftp
tar xvfz chkrootkit.tar.gz
cd chkrootkit-<version>/
make sense

Afterwards, you can move the chkrootkit directory somewhere else, e.g. /usr/local/chkrootkit:

How can I get a list of quotas assigned to my users and groups and of the space used by them?

repquota -avug

shows a list for both users and groups.

repquota -au

shows a list for users,

repquota -ag

a list for groups.

How can I set a limit as to how much space is available for a web site I put on my server? Like it is limited to 50 MB of space.

First, you have to enable quota on your system. Have a look at the quota section of the appropriate "Perfect Setup" tutorial for your distribution on HowtoForge.

After you've enabled quota on your system:

To set quotas for a user or group, use the setquota command (see

man setquota

for more information), e.g.:

setquota -g $group $blocks $blocks 0 0 -a
setquota -u $username $blocks $blocks 0 0 -a

Replace $group, $username and $blocks. Note: $blocks is the quota size in MB * 1024! To deactivate quotas for a user or group, run these commands and set $blocks to 0.

Quota does not work under SuSE 8.2!

On a standard SuSE 8.2 installation the quota module is not loaded into the kernel which is why

quotaon -avug

gives back an error.

Load the quota module manually with

insmod quota_v1


insmod quota_v2

To have those modules loaded on every bootup of the system please insert

modprobe quota_v1


modprobe quota_v2

in /etc/init.d/boot.local.

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