LJ Archive


Home Router Hacking

I thoroughly enjoyed Kyle Rankin's article “Practice Hacking on Your Home Router” in the October 2011 issue. Usually system cracking gets a bit deep for me, but this example was both practical and easy to follow—nice! One minor nit: data encoded into a URL is actually GET data rather than POST data. (I'll give him a pass this time on “hacking” vs. “cracking”.)

Grant Root

Kyle Rankin replies: Hey, precision is important, so thanks for the nitpick! You are right. The way I was submitting data to the router was GET data. GET or POST, the lesson is that if you accept input, sanitize it. If you are curious about why I use “hacker”, I explain it in detail in my November 2010 column “Some Hacks from DEF CON”.

Return to Solid State

I enjoyed getting a little comparative data on SSD performance [see Kyle Rankin's “Return to Solid State” review in the October 2011 issue]. My own experience is with an under-powered Acer Aspire One Netbook. One note, to further improve disk IO time and SSD wear, I load all partitions with noatime and nodiratime options in fstab.

Acer Aspire 532h Fedora 14 i686:


  • Cold boot to GNOME log in: 27 seconds

  • Log in to usable desktop: 2 seconds

  • Open Firefox to cursor at URL bar: 2 seconds

  • Open LibreOffice Write to blank doc: 2 seconds

Seagate ST9250827AS:

  • Cold boot to GNOME log in: 47 seconds

  • Log in to usable desktop: 16 seconds

  • Open Firefox to cursor at URL bar: 5 seconds

  • Open LibreOffice Write to blank doc: 7 seconds



Kyle Rankin replies: Thanks for the feedback—a good point about atime. I can understand that it makes sense to disable atime completely on some filesystems for speed (such as mountpoints dedicated to database storage), but for me, I find such benefit in atime for forensics that if speed is a concern, I like to use the new relatime option in the fstab. That way, I still get atime; however, atime writes are cached so it gives much better performance.

The Digital Subscription

I want to thank you for converting to all-digital download for Linux Journal. I see that in the past the magazine kept shrinking slowly over time, and now that you have gone 100% digital, it has grown in size! I think that is a plus for you. At first, I was worried about whether I would like the digital version, but after two months, I find I have begun to like it. Keep up the good work and the great articles!

Jim Brown

You bring up a point I hadn't even considered in regards to the “thickness” of the magazine. We can be a little more flexible now than we could be with paper. Thanks for the kudos as well. In all the chaos involved with the digital transition, the one thing we wanted to maintain was content.—Ed.

Digital Format Surprise

I'm a longtime reader, first time feedbacker. I just finished reading my first digital copy of Linux Journal, and although I thought I would hate the experience compared to reading in dead-tree format, I was pleasantly surprised. I spend all day staring at LCD pixels, and I rather disliked the idea of including my casual reading here. With the paper version of the journal, I often would read about something cool and say to myself, “Neat project I should check this out next time I sit and my computer.” Only I would never remember to remember to check it out. I love the HTML links built in to the digital version of the journal. It is so much more of an interactive experience. And that got me thinking, take one more step by creating a wiki-like version of the journal with user comments that show up next to articles, videos and so on—just a thought. Keep up the good work.


Cool idea Dan. As we learn to do this whole digital thing better and better every month, it will make new ideas feasible. Now that the entire production process is in-house (no more sending off to the printer), it makes experiments much easier as well. I totally agree regarding hyperlinks too. In the past, I've done my best to include short URLs in printed articles, but now we can use the real links and not worry about someone typing them in by hand. My favorite thing about digital though? Searching.—Ed.


I tried out the epub version of the September Linux Journal on my Nook Color and enjoyed reading it on that device—until I came to the graphics. It seems that images, such as a Bash screen in an article, are too small on the Nook to be read. They don't magnify either. I tried turning the Nook on its side for landscape view, which it will do with books and Web pages, but the pages wouldn't landscape. Yuck!

So, please study the epub version for a way to fix landscape or magnify images (perhaps embed a clickable bigger picture). Perhaps the problem is really with the Nook and epubs. In general, the Nook has problems with PDFs also. Usually they will magnify, but the landscape mode tends to be busted or useless with it still in a smaller portrait mode while turned 90 degrees.

I guess for now I won't be able to read LJ on my Nook with much success. I'll read it on my computer instead.


You are absolutely correct. Although we've been doing magazine layout forever, this whole “flowing text” thing is new for us. Trying to make epub files that work well on all devices is really challenging. We are working hard every month to make the experience a little better, and I think we've succeeded a little bit each month. Another challenge is example code. Because devices are so varied in size, it's rough to make the code “perfect” on each reader.

Like I said, we're working on honing our skills, so you should see improvement every month. Sending in comments like this really helps us determine what to focus on, so thank you again!—Ed.

Please Write about epub Tools

This month, I received Linux Journal in pure electronic form. I got it in PDF and mobi formats, and I can read it directly on my Kindle. I realized that since Linux Journal decided to deliver its content in e-formats, may be it can write about it. For instance, do an overview of available software tools, techniques for text formatting (especially code formatting suitable for gadgets), tools for transforming from one format to another and so on. I think it would be great topic for readers.


I agree! I want to see some articles on epub creation myself, so hopefully we can find some experts on the topic. I know there are many conversion tools out there, but what I'm looking for (and I think you're looking for) are tools to create them or edit them. The epub format offers so many cool features like table of contents, chaptering, graphic placement and so on, and I want to learn how to make or tweak my own. Thanks for sharing my interest.—Ed.

LJ Archive