July 2012 Issue of Linux Journal: Networking
Cast the Nets!
I thought we'd gone native this month and were going to show how to work nets and fish like the penguins do. I had a double-fisted, sheep-shanked, overhand cinch loop to teach you, along with the proper way to work your net in a snow storm. As it turns out though, it's actually the "networking" issue. That's still pretty cool, but instead of the half hitch, you get a crossover cable, and instead of my constrictor knot, you get load balancing.
Reuven M. Lerner starts out the issue with an article on Pry. If you're a Python programmer using iPython, you'll want to check out its Ruby counterpart, Pry. Although it's not required for coding with Ruby, it makes life a lot easier, and Reuven explains why. With a similar goal of improving your programming skills, Dave Taylor shows how to use subshells in your scripting. This doesn't mean you can't continue to write fun scripts like Dave's been demonstrating the past few months, it just means Dave is showing you how to be more efficient scripters. His tutorial is a must-read.
I got into the networking theme myself this month with a column on Webmin. Some people consider managing a server with Webmin to be a crutch, but I see it as a wonderful way to learn system administration. It also can save you some serious time by abstracting the underlying nuances of your various server types. Besides, managing your entire server via a Web browser is pretty cool. Speaking of "pretty cool", Kyle Rankin finishes his series on 3-D printing this issue. The printer itself is only half the story, and Kyle explains all the software choices for running it.
If Webmin seems a little light for your networking desires, perhaps Ratheesh Kannoth's article on the reconnaissance of the Linux network stack is more up your alley. Ratheesh peels back the mystery behind what makes Linux such a powerful and secure kernel, and does it using UML. If that sounds confusing, don't worry; he walks you through the entire process.
If you're actually creating or tweaking a network application, Andreas Petlund's article on TCP thin-stream modifications will prove invaluable. Anyone who ever has been fragged by an 11-year-old due to network latency knows a few milliseconds can be critical. Certainly there are other applications that rely on low network latency, but few are as pride-damaging as that. Andreas shows how to tweak some settings in the kernel that might make the difference between fragging or getting fragged. Unfortunately, no amount of tweaking can compare with the fast reflexes of an 11-year-old—for that you're on your own.
Stewart Walters picks up his OpenLDAP series from the April issue, and he demonstrates how to manage replication in a heterogeneous authentication environment. OpenLDAP is extremely versatile, but it still runs on hardware. If that hardware fails, a replicated server can make a nightmare into a minor inconvenience. You won't want to skip this article.
If my initial talk of fishing nets, knots and the high seas got you excited, fear not. Although this issue isn't dedicated to fish-net-working, my friend Adrian Hannah introduces the PirateBox. If the Internet is too commonplace for you, and you're more interested in dead drops, secret Wi-Fi and hidden treasure, Adrian's article is for you. The PirateBox doesn't track users, won't spy on your family and won't steal your dog. What it will do is share its digital contents to anyone in range. If your interest is piqued, check out Adrian's article and build your own. Yar!
This issue focuses on networking, but like every month, we try hard to include a variety of topics. Whether you're interested in Doc Searls' article on personal data or want to read new product and book announcements, we've got it. If you want to compare your home network setup with other Linux Journal readers, check out our networking poll. Perhaps you're in the market for a cool new application for your Linux desktop. Be sure to check out our Editors' Choice award for the app we especially like this month. Cast out your nets and reel in another issue of Linux Journal. We hope you enjoy reading it as much as we enjoyed putting it together.
Available to Subscribers: July 1
Shawn Powers is an Associate Editor for Linux Journal. You might find him chatting on the IRC channel, or Twitter
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Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
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Comments
Linux Journal - networking
Very good issue. I enjoyed each and every page.
Reply to comment | Linux Journal
Hi there, I would like to subscribe for this web site to get most recent updates, so where can i do it please
assist.
Another complicated linux
Another complicated linux journal! Networking is best online development solution. I enjoyed this article and it's the advertisers are pulling out it can only be a sign of increasing value of the publication push gifts. Thanks~! ;)
I was into this magazine till they sold out and got all popular
now they suck so bad. They just lost that raw unpolished quality. It's not authentic, there's just no soul anymore. SIGH.
:P
Imminent demise?
I looked over the more recent issues of LJ and I noticed that there are fewer adds every time. In fact most of them are to LJ itself. If the advertisers are pulling out it can only be a sign of decreasing quality of the publication.
No need to infer quality
No need to infer quality trends through advertising content; why not look at the actual articles and decide for yourself about trends in quality?
I've been a subscriber for 10+ years
So I have a pretty good idea of the quality of the articles and how it varied over time.
I remember the journal before Nick Petreley was in charge and it was the best Linux publication out there. Nick's efforts to lower the quality were obvious (3 columns by Jon "Maddog" Hall in the same issue, changing the format of the magazine for no reason, lots of complaints from the readers) and I had high hopes when he was kicked out.
In fact I had a break in my subscription until he was kicked out and I renewed only when I learned he was gone. Nobody bothered to remind me to renew my subscription when Nick was in charge, a clear sign that he wanted to drive subscribers away.
I had high hopes when I saw that a new group of people took over, but then regulars like Mick Bauer and Marcel Gagne have stopped publishing and Shawn Powers started allocating more and more space to himself. I have to say, his writing is not the most informative out there.
So back to the ads, their disappearance is just a consequence of declining quality, not the cause of it. I will just let my subscription run out and will not renew.
Linux Journal: Networking
I enjoy reading and found more interesting on this new OS you have in here. I've heard this OS but I have try using this one. Were on Windows 7 and XP from past. Thanks for sharing this ideas here.
Reply to comment | Linux Journal
Good respond in return of this matter with solid arguments
and explaining the whole thing regarding that.