Link: 4 Tools to Securely Delete Files from Linux

Any computer user with normal level skill set knows that any data removed from computer system can be recovered later with little bit of efforts. This is a good thing in the scenario when you have accidentally deleted your critical data. But in most cases, you don’t want your private data to be recovered easily. Whenever we remove anything, the operating system deletes just the index of the particular data. It means that data is still there somewhere on the disk, this method is insecure, as any smart computer hacker can use any good data recovery tool to easily recover your deleted data. Linux users utilizes the well know “rm” command to remove data from their operating system, but “rm” command works in the conventional fashion. Data removed using this command can be recovered by special file recovery tools.

Let’s see how we can safely and completely remove files/folders from our Linux system. The methods mentioned below remove data completely so it becomes very hard for recovery tools to find traces of the actual data and recover it.

Full article here:
4 Tools to Securely Delete Files from Linux (LinOxide)

Links: Bash by Example, Parts 1-3

You might wonder why you ought to learn Bash programming. Well, here are a couple of compelling reasons:

You’re already running it

If you check, you’ll probably find that you are running bash right now. Even if you changed your default shell, bash is probably still running somewhere on your system, because it’s the standard Linux shell and is used for a variety of purposes. Because bash is already running, any additional bash scripts that you run are inherently memory-efficient because they share memory with any already-running bash processes. Why load a 500K interpreter if you already are running something that will do the job, and do it well?

You’re already using it

Not only are you already running bash, but you’re actually interacting with bash on a daily basis. It’s always there, so it makes sense to learn how to use it to its fullest potential. Doing so will make your bash experience more fun and productive. But why should you learn bash programming? Easy, because you already think in terms of running commands, CPing files, and piping and redirecting output. Shouldn’t you learn a language that allows you to use and build upon these powerful time-saving constructs you already know how to use? Command shells unlock the potential of a UNIX system, and bash is the Linux shell. It’s the high-level glue between you and the machine. Grow in your knowledge of bash, and you’ll automatically increase your productivity under Linux and UNIX — it’s that simple.

Full articles here (source: funtoo linux):
Bash by Example, Part 1 – Fundamental programming in the Bourne-again shell
Bash by Example, Part 2 – More bash programming fundamentals
Bash by Example, Part 3 – Exploring the ebuild system

Link: Crontab Generator

Those of you that use Webmin already have something very similar to this in the System > Scheduled Cron Jobs tab, but for those who aren’t using Webmin, there’s this:

If you want to periodically perform a task (e.g. sending Emails, backing up database, doing regular maintenance, etc.) at specified times and dates, there are two ways to set scheduled tasks:

Method 1: Use our online cron job service that will save you a headache.

Method 2: Use Cron available in Unix/Linux systems.

If you go with method 2, the following generator can help you produce a crontab syntax that you can copy & paste to your crontab file (You can open the file by using command crontab –e). Below the generated crontab syntax, a list of run times will be displayed too. The predictions will help you ensure that you set the time and date right.

Link to full page:
Crontab Generator