Diary of a Network Geek

A short film about a classic sci-fi problem.

It’s another Friday, and, as usual, my poor, little brain has been cooked pretty well this week. If you’re feeling the same way, we’re both in luck because I have the perfect 20 minute distraction from your week. I don’t want to spoil anything, but this very well done science-fiction short takes a fresh look at a classic paradox. The production values are high, as are the stakes. It’s thoroughly engaging and doesn’t talk down to the hard-core, old-school fans of science-fiction. If that sounds like a great way to take a break today, check out Hyperlight by Nguyen-Anh Nguyen on Vimeo via IO9.com.

And, hopefully, you’ll come back next week for something else cool for your Friday afternoon!

This post originally appeared on Use Your Words.

So, I’ve been writing a bit of Perl again…

It’s kind of a long story that’s really rather boring, I think, but we’re changing e-mail providers at work again. They’ve got a new system to try and reduce spam that involves a challenge-response system and a whitelist.
For those not familiar, it works like this: The first time you send an e-mail to their servers, the anti-spam system fires back a verification e-mail to you. That e-mail verifies that you’re a human and not a spambot by asking you to click on a link. When you click the link, it adds you to the system’s whitelist and lets your e-mail through from then on. Pretty good system, actually. And, about the only way to assure virtually no spam gets through.

Well, to minimize hassle to our customers, we decided to pregenerate a whitelist of known, good e-mails. Naturally, that task fell to yours truly.
So, I turned to my old pal Perl. The mail is mostly stored in a UNIX mail format called “mbox”, which, luckily for me, is basically a flat file. It’s like a giant text file that has a lot of extra junk in it that no one but mail programs care about. So, the first thing I did was dig up code, and modifiy it, to pull all the e-mail addresses out of those mbox files. I called it “emailpull.pl“. That managed to pull all kinds of addresses. In fact, after I culled out the obviously bad address and eliminated the duplicates, I had a little over 4000 addresses.
Well, that was just a little too many for me to just dump into a whitelist without some kind of extra verification. So, I hunted around and found a handy CPAN module called “Mail::CheckUser” which is meant, you guessed it, to help check e-mail users. A little finagling with the code and I put together “emailverify.pl“. That little badboy takes a list of e-mail address, in text file form, and verifies them with the alleged e-mail host. Works like a charm!

Oh, and if you’re a Perl fan/addict/whatever, check the links to the code. They take you to a place called PerlMonks.org. They used to be the place to get code and help and, well, everything Perl related. But, you know, lately? Not so much. When I was there putting these two snippets of code up, there was a whole big bruhaha going on about membership to some internal, super-secret cabal group. And, there’s a lot of focus on getting levels and all sorts of junk like that. Which is ironic, to me, considering that Larry Wall, the guy who wrote Perl, did so in the hopes it would draw people together in harmony and spirit of helpfulness.
Ah, well, at least I got my task accomplished. Well, at least it will be by morning. That second script was still running when I left the office.

Update: That second script, when it was done running, reduced 4060 e-mail addresses down to 3255 validated e-mail addresses. Hopefully, it culled all the potential spam originators!

This is cooler than it sounds.
No, really. Please, let it be cooler than it sounds so I feel better about the way I spent my day. Please?
Honest, using the PDF::API2 CPAN module is much more challenging than it sounds. I spent most of the afternoon trying to figure out how to force a second page into my PERL-generated PDF. Why? Because, I want a nice title page for my documentation. Also, I see applications for this frightening technology beyond the scope of my project. See, one of the things we do is prepare, and sell, documentation for our great, big, huge, expensive cranes. That documentation is in, you guessed it, PDF format. A fair portion of this documentation is based on AutoCAD drawings that have been convertd to PDF. So, now, all I have to do it automate most, if not all, of that process and I’ll save a ton of time, which, according to the “time=money” formula will “impact the bottom line”, as they say in boardrooms. Cool. In other words, I found a way to justify my personal project (the server inventory script) by applying the things I’m “testing” there toward the automation of a dirty, low-end, repetetive task that no one likes doing (compiling the documentation PDF). Very cool. And, thanks to all this work on PERL this week, I’ve added a new category: PERL.
Oh, yeah, here is the PERL PDF Example code. Enjoy!

This is sort of the long way around, but…
Well, I have a dream. I dream of a single, giant PERL script that does a complete server inventory, no matter what version of operating system it’s running. Why? Look at my resume. Notice how many times I’ve changed jobs? Every time I hit a new gig, I look at their server documentation, if they have any, and ask how old it is. 80% of the time, no one knows how old it is. The rest of the time, it’s so old and out of date as to be totally irrelevant. Of course, no matter the state of their documentation, it always falls to me to create it or update it. Hence my quest for a single, glorious PERL script that checks everything that matters on an individual server and drops it into a report, or at least a text file that I can make into a report.
The biggest stumbling block to my vision of this splendiferous chunk of code has almost always been the first one: figuring out which operating system the target is running. Well, not any more. No, my faithful readers, including my ex-wife and her new meal-ticket, now I give you Step One in Uncle Jim’s Master Plan for Network Domination.
PERL OS Version checker

Well, at least yesterday wasn’t a total waste.

Oh, how sweet is this!?
So, I was looking around the other day for a PERL script that would send me an SMTP mail notification from a Windows 2000 server at a remote location, so that I’d know what their IP address had been changed to after a reboot. (It’s a long story, but it involves a VNC server, a cable-router, and a bad power grid.) And, whenever I search for this kind of thing, I go to my backup/long-term memory archive, Google, and do a search. Guess what I found? A whole set of web pages at Microsoft dedicated to Windows-centric system admin and monitoring PERL scripts. Oh, I think I’m in heaven!
I’ve been looking for this kind of thing for ages and ages. I have no idea why I never found it until now, but, well, here it is! Now, I can develop that massive, PERL-based auditing system that I’ve always dreamed of having! YEA!

It’s beyond me today, but…

Well, let’s just say this gives me something to shoot for in my PERL goals. I found Advanced Perl Programming on the discount shelf of a local bookstore, so I snapped it up, but it’s going to take me a while to “get” everything in this book. I mean, they’re talking about really advanced database access, incorporating C programs, and making GUI interfaces with Tk. That’s way, way beyond the little bit of text processing that I’ve managed with my own PERL efforts. Still, I’ve always felt that getting in “over my head” and fighting my way to the top, so to speak, is the best way for me to learn anything of value. And, it does tend to keep me challenged. So, while I love where this book is going, I probably need to stick with the PERL Cookbook. But, I’ll get there eventually. I swear it.

Well, I’ve done it now!

Okay, so I’ve been messing around with PERL for Netware and I came up with at least one thing that I thought was useful. I call it “dfmail.pl”, which is short of DiskFreeE-Mail. It’s a simple little script that will check the available space on all the volumes of a server and e-mail the results to the user of your choice. You will have to edit the script to set the e-mail address, but otherwise, it should run okay. Oh, I tested it on Netware 5.1 servers, with the latest service pack, so I have no idea how well it will work on Netware 6. If anyone tries it, let me know!

Download DFMail.ZIP

I know why the PERL developer cries…

Sometime ago, I wrote an entry about PERL on Netware. At the time, I wondered why no one used PERL for Novell System administration. Now, I know. Novell has virtually no documentation on how PERL interacts with Netware. There are a few, simple example scripts and a couple of suggestions for things to do with it, but that’s about it. How frustrating! Here I am, having actually gotten a little bit of PERL savy and to what end? My favorite server OS supports it, technically, but they offer virtually no information about how to actually make use of it! Argh!

Ah, well, now that they’re getting into the Linux arena maybe we’ll start to see more support for Open Source and “hackerish” tools, like PERL. I sure hope so…

Hey, did you know you can run PERL on Netware?

Yeah, it’s been there since Netware 4, actually, though no one really mentioned it at all until Netware 5. I started paying attention to that fact about two years ago when I started getting into PERL for my websites. But, now, it’s a default component in the standard install! So, why don’t I hear about anyone leveraging this? Well, I’m not sure about anyone else, but I intend to get some use out of PERL on my Netware servers.
Two weeks ago, I bought PERL for System Administration with the idea that I would use it, and code from the PERL Cookbook, to make my life easier. Why not, I thought, make a set of scripts that I can use or adapt for Linux, Netware and Windows? Sounds like a great idea, right? Well, we’ll see. I hope it’s a great idea, anyway. At the very least, I should be able learn a bunch more about PERL!
And, while I’m working on it, here’s a German site(in English) that has all kinds of scripts for PERL on Netware. Enjoy!

Updated random resolutions!

I haven’t made formal New Year’s Resolutions in a long, long time because, honestly, if I’m relying on making myself a promise on a certain day to follow through, it’s not likely to actually happen. At least I know that I’m alone, which is why gyms and churches are both bursting at the seams in January but thin out by April. Still, it’s traditional, so I’ll share, my own little solution to the New Year’s Resolution “problem”, which has been freshly updated.
Back in the day, when I still had delusions that I could make myself into a decent programmer, I whipped up a New Year’s Resolution Generator. At the time, I was studying Perl, which is what I wrote it in then. This year, though, I updated that sad, old Perl CGI program to the much more modern PHP. So, now, instead of getting an error message, you actually get the fun toy.
I based it, in part, on some ideas from the Worst Case Scenario Survival Handbook: Holidays, but I have to admit, I threw in some of my own warped sense of humor. And, I weighted things a little more toward heavier drinking and looser morals because I figured those were the resolutions that would be easier to keep and I figured they’d be funnier.

In any case, it was apparently funny enough that Comedy Central Insider linked it in their blog back when I first released it all the way back in 2006. Which is pretty cool, no matter how long ago that was and how many technologies and upgrades have come and gone. Besides, can completely random “advice” from a website really be any worse than the suggestions you got from family over the holidays? In today’s world of chaos and unreality, it honestly doesn’t seem as bad an idea as it used to! So, why not give it a shot yourself? You don’t even have to share about it publicly. No one will know but us!

And try to have a good year, no matter what happens. Make time to love your loved ones, do good work, and add something positive to the world. Or one of the random resolutions. Whichever seems likelier to produce good results.

This post originally appeared on Use Your Words, in spite of the fact that the actual New Year’s Resolution Generator resides here! It’s a crazy world!