Server hardening. The very words conjure up images of tempering soft steel into an unbreakable blade, or taking soft clay and firing it in a kiln, producing a hardened vessel that will last many years. Indeed, server hardening is very much like that.

For this article, I thought it would be beneficial to go back to some basics of shell scripting and look at how functions work. Most script writers probably eschew using functions because it's a bit antithetical to how scripts tend to evolve, as a sequence of commands on the command line that are captured in a file.

When the folks who make the Raspberry Pi made good on their plan to release a multi-core version of the tiny computer with 1GB of RAM earlier this year, I saw it as the perfect opportunity to put the single-board Linux box to work—real work—in our company's network operations center.

Conjecture on cracked primes for the Diffie-Hellman asymmetric algorithm is in recent news, suggesting that several nations have broken primes in common use and can read all traffic:

I wake up in the middle of the night, mouth parched and vision blurry, and fumble around to find my iPhone. I press my thumb to the fingerprint scanner, and in the dim blue light, just out of instinct, I squint at the screen, find the right app, open it, and check the ambient temperature and air quality indoors.

Will the keyboard click enough? Is it small enough? Is it free enough? Find out below.

Large enterprises and nuclear laboratories aren't the only organizations that need an Internet access policy and a means of enforcing it. My household has an Internet access policy, and the technique I've used to enforce it is applicable to almost any organization. In our case, I'm not too concerned about outside security threats.

I love SSH. I mean, I really, really love SSH. It's by far the most versatile, useful, amazingly powerful tool in my system administration quiver. One of the problems with SSH, however, is that when it dies, it doesn't automatically recover. Don't get me wrong.

If you follow my columns in Linux Journal, you probably are aware that I'm a big fan of the command line. When it comes to getting things done efficiently, most of the time the command line can't be beat.

Like IPv6, DNSSEC is one of those great forward-looking protocols that unfortunately hasn't seen wide adoption yet. Before I implemented it myself, I could see why. Although some people think BIND itself is difficult to set up, DNSSEC adds an extra layer of keys, key management and a slew of additional DNS records.