ServerBuddies Support Blog

How do I keep my crontab from sending an email every time it runs?

Add the following > /dev/null 2>&1

The >> /dev/null 2>&1 part means to send any standard output to /dev/null (the linux trash can) and to redirect standard error (2) to the same place as the standard output (1). Basically it runs the command without any output to a terminal etc.

If you wanted to save the output of a certain command you can replace the “>> /dev/null 2>&1″ with “>> /home/user/script.log 2>&1″

Advanced Policy Firewall (APF) is an iptables(netfilter) based firewall system designed around the essential needs of today’s Internet deployed servers and the unique needs of custom deployed Linux installations.

The offical home page for APF is located at:

http://www.rfxnetworks.com/apf.php

If you are configuring iptables in your own custom kernel then you
should be sure that the following modules are compiled with the kernel for
modular support:

If you would like to make sure you support these modules then you can take a look inside of /lib/modules/kernelver/kernel/net/ipv4/netfilter/ directory.

Installation

The installation setup of APF is very straight forward, there is an included
install.sh script that will perform all the tasks of installing APF for you.

Install

If one so desires they may customize the setup of APF by editing the variables inside the install.sh script followed by also editing the path variables in the conf.apf and internals.conf files. This is however not recommends and the default paths should meet all user needs, they are:

The first is to setup APF in the init system with chkconfig (done by
default during install), as detailed below:

General Usage:

The /usr/local/sbin/apf command has a number of options that will ease the
day-to-day use of your firewall. Here is a quick snap-shot of the options:

Installing Perl Modules.

Perl Modules can be obtained from the CPAN (Comprehensive Perl Archive Network) at http://search.cpan.org.

The easiest way to install Perl modules on Unix is to use the CPAN module. For example:

DBD::mysql is the Perl5 Database Interface driver for the MySQL database.

To find a particular module, use the i command, followed by an expression that you want to search for:

CPAN.pm will go out to the CPAN mirrror that you selected, download the list of modules, and tell you which ones match the search word.

To install a module, just type:

CPAN.pm takes care of the whole process. It downloads the compressed file, unpacks it, builds it, and installs it all for you, unless there is a problem with the installation process. If there are other modules on which this module relies, it will also download and install those.

Installing and Configuring CSF Firewall

ConfigServer Firewall & Security. A Stateful Packet Inspection (SPI) firewall, Login/Intrusion Detection.

This article demonstrates how to install and configure the CSF (configserver) firewall. CSF can be used on a wide range of Linux systems, including those running cPanel.

To configure CSF modify the config files in /etc/csf/ - or if you are running WHM you can modify the CSF settings in there. By default CSF opens the standard cPanel ports.

If you have APF + BFD you will need to disable it, you can use the following to do so:

To Fix Common reasons for quota problems

Run the following command as root user.

Try finding other files owned by the user.

This will list all files owned by this user that could be affecting the quota reported by Cpanel.

Cpanel/WHM sometimes has problems with the user quota files causing all users accounts to have unlimited disk space available or 0 megs of disk space in use.