Lifelong Learning a blog of all the things I've learned about…


Overlapping Subnets is never a good thing…

Cartoon Crowd, Network ProxiesRecently I had an issue that I couldn't find a solution for using the power of Google. My company has a wonderful tool from BMC called ADDM. It's an enterprise tool that allows you to scan your network and discovery the things that live on the network. One of the configuration tasks is to provide the tool with a set of subnets to scan and when to scan. Unfortunately I can't do subnetting in my head and the list of subnets I did have were of all sizes. What I found out quickly was that I had overlapping subnets supplied to the application, this meant that some subnets were getting scanned multiple times a day which isn't ideal in the enterprise. I could get a simple CSV extract of all the scans I had configured and what subnets were in each but I couldn't find any tools that would allow me to load up that CSV file and identify the overlaps.

Thankfully I have a rather long background in development and after spending about an hour building it in Visual Studio 2013, I had a self-made tool that would load the extract of scans and subnets from ADDM and tell me where I had overlap. It took me about five minutes to remove the overlaps and I was done! All in, I had invested more time searching for a solution than it took to make my own! Just goes to show you how limited life can be if you don't have the ability to find your own solutions to life's problems.

For those who may use ADDM at work, or really anyone who has a list of subnets and wants to identify overlaps. The CSV file was a simple select all and extract to CSV from ADDM. I removed the header and made user all lines had quotes around the subnets. Format is below and I've attached the code to this post, you can find the .exe in the bin folder after you extract the zip. As always this is open to the world but unsupported, use at your own risk. Requires .NET 4 framework.

Each line should look like this (scan or subnet name a comma and then a comma delimited list of subnets in CIDR format with quotes around the list):

Subnet or Scan name,"one or more subnets comma deliminated in CIDR format,"

Title: SubnetOverlapTester (96 clicks)
Size: 258 kB


blink(1) mk2 for the win…

blink(1) mk2 by ThingM

Last week I finally received my two new shiny blink(1) mk2 USB RGB "things"; these were rewards for helping fund the KickStarter project from ThingM. The mk2 is the second generation and even cooler version of thier RGB blink(1) devices. They are hackable USB powered indicators and I had a project in mind for one my mine which I jumped on right away. I wanted a way to indicate to cube mates when I was on the phone and shouldn't be disturbed (folks are always interrupting as they can't tell I'm on the phone before they barge in asking questions, awkward for all involved really). These blink(1) devices are the perfect fit for such a problem. I taped one up on my monitor, fired up Visual Studio and build myself a quick system tray applcation that will allow me to change the indicator color with a single click. The application also automatically switches the indicator when it detects I'm idle for 5 minutes. As soon as I interact with my computer again, the indicator automatically switches the indicator back. Super quick project and couldn't have been possible without the .Net library for the blink(1) by Jean-Francois Talbot and the great hardware from ThingM. As always source code is below and I've even recorded a quick video of the system working. Now to find a project for the other blink(1).....

Title: blink(1)SysBarCTRL (544 clicks)
Size: 682 kB


Dynamic DNS Updates For Multiple Hosts On A Synology

Need to update multiple hosts on your Synology? Frustratingly you can't update multiple hosts with the GUI on a Synology. Once you select as your provider you'll see there is only the option to enter a single host to be updated. After you add that host, the option to select in the dropdown for the providers so you could add another record is gone. I was able to accomplish this with little effort and here's how you can to.

Since I'm attempting to host a few personal blogs on my Synology, I needed several different domain hosts to get updated. I only tested this using the same credentials with different hosts targets. You may very well be able to do this for different accounts if needed.

First, you need to make sure you have SSH enabled on your Synology (if not, google it). SSH into your box as root and type in the following command:

vi /etc/ddns.conf

Now you should see the contents of the ddns.conf file on the screen. You'll want to copy all the values exactly except for the "hostname" line which should be changed to match the additional hostname you wish to have updated. You must also add a number the the block the update "[]" should become "[]" and if you wanted a third hostname updated, "[]", etc.

All done, go back to the GUI and open the DDNS service and you should see entries for all the hosts you manually entered. Hope this helps someone else who has a similar need as I did...

Example of what your ddns.conf file will look like.

Example of what your ddns.conf file will look like.


Filed under: Computers, Software 2 Comments

I <3 Raspberry Pi

I finally got my shipment of Raspberry Pis today and I am stoked! I didn't pay the crazy prices on eBay and so I now have a $36 computer. I've allocated both of my PIs as XBMC boxes to power my basement and living room TVs. I had been running a BoxeeBox and while I initially loved it, I've grown to HATE it. They should rename it "FlakeyBox"; a $200 box of crap.

Anyhow, I spent about 30 minutes working on it and I have my first Pi up and running and streaming 1080 video to my TV without issue. If you are in the market for a Pi allow me to suggest Adafruit. If you want information on how you too can use a Raspberry Pi as a media center, check this site out. There are several different firmwares available for XBMC but I've settled on Raspbmc for now, it's fast enough for daily use and seems very stable.


Update (2/11/2013):

Make sure you use a powered USB hub and pick up one of these power supplies for your PI, otherwise it'll be very unstable. I learned this the hard way. These power supplies from AdaFruit supply 5.25V to the PI which helps with it's rather shoddy power design which will allow the board to become under powered and reset.


Arduino Clone Powered RGB Keyboard Light

I recently remodeled my office as I'll be working from home full-time starting in March, it's amazing what you can do with $1k dollars at Ikea! Anyhow, love my office setup, especially my desk but I had one nagging issue, I couldn't see the keys of my keyboard easily when the office was dark. My wife subltly suggested I get some sort of light to put underneath my desk to illuminate the keyboard. Ah, how I love my wife and her fantastic ideas...   

Obviously, I wouldn't settle for some store bought device, I'm a self-declared "Maker" after all! After several days of tossing around ideas in my head, I decided it'd be super neato to have an RGB LED board under my desk and have it connected and powered by my computer. I'd then have some software sit in my system tray so I could control the board (colors and etc). Yeah, that's exactly what I needed!

So, yesterday I decided I'd set out to build it with only the parts I had on hand, I'm having a baby and thusly on a very restricted hobby budget!

Since I'd be etching the board myself, I knew I'd use through hole components to make life easier and I centered the project around an ATMega328 since I wanted to use serial communication with my PC and the quickest path was to use Arduino programming language (using a FTDI cable). I also wanted to utilize some 5mm common annode RGB leds I had on hand from a previous project but I wanted at least 5 to make sure I had good illumination on the keyboard and I wanted to use PWM to allow color mixing...well, a few 2907A transistors and a dozen or more resistors later I had a schematic I could be proud of. 

Eagle Board Layout for my RGB keyboard light

The layout of the board was easy, I had a 3"x4" single sided copper photoetch board, so I laid all my components out to fit the whole board (I didn't want to cut it). I also learned the hard way that small traces are a pain in the butt when etching your own boards so I set my traces to 24mil, genrously large enough to not create issues during the etch. I didn't get any pictures of the board before it was mounted, sorry. You can always refer to the board image in the zip file attached to this post.

Once I had soldered all my components on the board, I threw in an ATMega328 micro that already had the Arduino bootloaded burned. Hooked up my FTDI cable and my test sketch worked flawlessly. Whew, nothing like going from concept to finished board with no testing to get the nerves going!

With the board testing out good, I set about coding up a C# app to control it. I had previously worked with serial comunications using C# and an Arduino which I talked about in this post so the C# code was really more about figuring out how to get a sys-tray app working as I wanted than worrying with the serial communications. I think it took me about 2 hours from start to finish to get things to a point I was happy with (nice and quick not nice and neat). I'm a developer by trade so I knew all along this would be the easiest part for me.

Well, a very quick project for me, one I'm quite proud of actually. As always I've attached high resolution pictures, eagle schematics, Arduino sketch and this time the Visual Studio solution in the zip below.

Drop me a note if you have any questions about this project, I think it's a fun and easy project for folks to test out thier etching and coding skillz!

Check out the videos below to see the software and board in action!

Title: KeyBoardLightProject (514 clicks)
Size: 19 MB

Title: KeyBoardLightProject (514 clicks)
Size: 19 MB


My FreeNAS Build (Part 3 of 3)

So after a few months of using FreeNAS I've decided I can't live with the insanely slow transfer speeds. Unfortunately FreeNAS is built on FreeBSD and has a terrible port of SAMBA service. It's so slow it's painful!

I'm not bashing on the developers, they've done a fantastic job with the tools provided to them under FreeBSD, I just think the call to use FreeBSD was a bad one, especially when the software is supposed to be a NAS and has a known poor implementation of SAMBA.

At any rate, it's my opinion that anyone who is technical stay away from FreeNAS and just utilize Ubuntu server or the like. For those who are not technical, I'd suggest Microsoft's Home Server, it's performance on file transfers smokes FreeNAS and it's fairly moron-proof.

As for me, I'm installing Ubuntu Server 10.4 and never looking back. My goal was to evaluate FreeNAS and it's core purpose was file storage which means lots of file transfers and that's the one thing it sucks the most at...sorry FreeNAS, I've found another and I'll never look back.....

So if you've been following my FreeNAS posts, you know I gave FreeNAS a fair shot, if you haven't been following along, let me save you some time by saying don't waste your time with FreeNAS. If you are just in love with the idea of FreeNAS wait for OMV (Open Media Vault)....

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