Prevent users from logging into your system

If you are a system administrator who allows remote access to your server or desktop, you may want to disable certain users from logging into the system both remotely and locally. This article will explain how to prevent certain users from logging into your Linux machine via SSH (OpenSSH_4.4p1) and FTP (vsftpd 2.0.5).

First we must understand that in most cases there are two different ways an allowed user may be logging into your Linux server. Continue reading

Staying Secure with Nessus Vulnerability Scanner

This is a simple walk through guide to installing nessus, configuring nessus, and running the popular Nessus Vulnerability Scanner on Linux. From the Nessus website: Nessus is the world’s most popular vulnerability scanner used in over 75,000 organizations world-wide. Many of the world’s largest organizations are realizing significant cost savings by using Nessus to audit business-critical enterprise devices and applications. Continue reading

Simple Samba Slackware Setup

If you are wanting to connect your Windows machine(s) to your Linux machine(s) over your network, then Samba is what you need. Essentially, Samba allows your Linux machine to communicate with your Windows network to share files, resources, and printers. This document will cover the steps of installing and configuring Samba on Slackware 11.0.0. Continue reading

8 Windows XP Tips & Tricks

Following are a collection of nifty Windows XP Tips & Tricks that I have gathered and used over time.

  • Delete Files Immediately
    This will allow you to delete files from your system without sending them to the recycle bin first.
    Select Start > Run… type gpedit.msc then select User Configuration > Administrative Templates > Windows Components > Windows Explorer then locate the ‘Dsupo not move deleted files to the Recycle Bin‘ setting and set it.

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Setting up a Syslog Server

One very important aspect of computer security and hack prevention is the collection and assessment of system log files. In the mind of a hacker, when gaining unlawful entry to a system their first instinct is to cover all traceable tracks. This means deleting log files and possibly even setting up backdoors to enter again at will sometime later in the future. It is important, as a system administrator, to ensure that even if your system has been broken into or tampered with, that you have traceable evidence to figure out exactly what went wrong, and where it went wrong. Hackers tend to tamper with system logs making this sometimes impossible to figure out. Setting up a remote syslog server for all of your servers to send their logs to is how we can ensure that your logs will be completely accurate and un tampered with.

The syslog server configured in this example is an old 486 with an 8GB hard drive, running Slackware Linux 10.2. However, the configuration and commands will work for just about any Linux distribution.

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SSH + Screen = Easy Administration

I have access to a numerous amount of Linux machines for work and personal matters. Instead of having a ton of different SSH or PuTTY windows open, each connected to a server that I administrate, I decided to use screen to connect to all of them, and manage each one in a different screen window.

Before getting into my screen configuration, its also important to note that on top of my screen setup, I have also configured SSH to authenticate via SSH keys, so I wouldn’t have to always type the password when admining from my “playbox”.

Here is how I set up SSH keys.

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