SysAdmin

DNSSEC Part I: the Concepts

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.

SIDUS—the Solution for Extreme Deduplication of an Operating System

SIDUS (Single-Instance Distributing Universal System) was developed at Centre Blaise Pascal (Ecole normale supérieure de Lyon, Lyon, France), where one administrator alone is in charge of 180 stations. Emmanuel Quemener started SIDUS in February 2010, and he significantly cut his workload for administering this park of stations. SIDUS is now in use at the supercomputing centre PSM

Protect Your Ports with a Reverse Proxy

In a previous article, I discussed Apache Tomcat, which is the ideal way to run Java applications from your server. I explained that you can run those apps from Tomcat's default 8080 port, or you can configure Tomcat to use port 80. But, what if you want to run a traditional Web server and host Java apps on port 80? The answer is to run a reverse proxy.

Two Pi R

Although many people are excited about the hardware-hacking possibilities with the Raspberry Pi, one of the things that interests me most is the fact that it is essentially a small low-power Linux server I can use to replace other Linux servers I already have around the house.

Advanced Hard Drive Caching Techniques

With the introduction of the solid-state Flash drive, performance came to the forefront for data storage technologies. Prior to that, software developers and server administrators needed to devise methods for which they could increase I/O throughput to storage, most of which resulted in low capacity caching to random access memory (RAM) or a RAM drive.

Manage Your Configs with vcsh

If you're anything like me (and don't you want to be?), you probably have more than one Linux or UNIX machine that you use on a regular basis. Perhaps you've got a laptop and a desktop. Or, maybe you've got a few servers on which you have shell accounts.

Fight the Good Fight with SmokePing

My Internet connection is unstable. I do realize ISPs generally claim some downtime is expected, and service is not guaranteed, and countless other excuses are common for intermittent service. I currently pay $120/month for business-class service, however, and I expect to get reliable Internet access on a regular basis.

Raspberry Strudel: My Raspberry Pi in Austria

I remember my first colocated server rather fondly. It was a 1U Supermicro that had been decommissioned from my employer after a few years' service. Although it was too old and slow for my company, the 800MHz CPU, 1GB RAM and 36GB SCSI storage was perfect for my needs back in 2005. A friend was kind enough to allow me to colocate the server at his facility for free.

Raspberry Pi: the Perfect Home Server

Ever since the announcement of the Raspberry Pi, sites all across the Internet have offered lots of interesting and challenging uses for this exciting device. Although all of those ideas are great, the most obvious and perhaps least glamorous use for the Raspberry Pi (RPi) is creating your perfect home server.

More PXE Magic

In this article, I've decided to follow up on a topic I wrote about not in my column directly, but as a feature article called "PXE Magic" in the April 2008 issue.

Dynamic DNS—an Object Lesson in Problem Solving

The other day in the Linux Journal IRC room (#linuxjournal on Freenode), I was whining to the channel about no-ip.com deleting my account without warning. My home IP address hadn't changed in a couple months, and because there was no update, it appeared abandoned.

Home, My Backup Data Center

New Linux users often ask me "what is the best way to learn about Linux?" My advice always comes down to this: install and use Linux (any distribution will do but something stable works better), and

How to Deploy A Server

When I write my column, I try to stick to specific hacks or tips you can use to make life with Linux a little easier. Usually, I describe with pretty specific detail how to accomplish a particular task including command-line and configuration file examples. This time, however, I take a step off this tried-and-true path of tech tips and instead talk about more-general, high-level concepts, strategies and, frankly, personal opinions about systems administration.

Troubleshooting with Telnet

Poor telnet, it used to be the cool kid on the block. It was the program all sysadmins turned to when they needed to connect to a remote server. Telnet just wasn't that good at keeping a secret—all communication went over plain text—so administrators started switching to SSH for encrypted remote shell sessions.

Android System Administration Utilities

“Change is inevitable in a progressive society. Change is constant” Benjamin Disraeli 1867. Quite a fitting quote if I say so myself. When I started in systems administration back in the mid 90’s everything was done either remoted in from your desktop, a server, or you plugged a terminal into the back of the server.