Getting Started with Raspberry Pi
What and Why?
(If you’re here because you googled for a RPi tutorial, I’d suggest skipping to the next section)
I’ve recently throttled back on being all .NET all the time, mainly because I’m trying to spend more time working on my home automation. Toward that end, I recently picked up a Raspberry Pi. Since the organization’s home page neglects to include an elevator pitch as to what it actually is, I’ll summarize by saying that the Raspberry Pi (or RPi, for short) is a fully functional computer that’s about the size of a credit card and contains a good cross section of the device I/O that you might want, including audio, HDMI, USB, and ethernet. Oh, and they’re $35.
I’d imagine that most of you reading have either heard of this or, if you haven’t, you’re thinking of half a dozen uses now that you’ve read my description. But if you aren’t, here are a few uses you might find attractive: tiny media PC, small robot controller, car OBD troubleshooter device, Roomba brainwasher (I totally want to do this and use it to chase my cats around). One could also use it, as I plan to, for home automation.
My purpose here with my first RPi is going to be relatively simple — I’m going to offload the home automation controlling functionality of my home’s server onto it. The server I’m currently using is a repurposed dinosaur that I took with me to college (P2, 400 MHz processor, and tricked out to the max in slots with a whopping 3 128 MB sticks of RAM). It chugs along with an old Fedora installation, running a web server, SVN, a few databases, samba, and a few other goodies, as well as being hooked up to my big external drive where media is stored and eventually whisked into the cloud via Crash Plan. Add to this the fact that there’s a firecracker module plugged into its serial port to make the jump from my software to the electrical, and this is a pretty busy old machine that may not be long for this world. So I’d like gradually to parcel out its functionality to a handful of other machines to minimize my exposure to an extremely annoying failure, and the RPi is perfect, spec-wise and form-factor-wise, for the home automation web server.
Before Getting Started
So your Pi arrived in the mail, it has no installed OS, no instructions, and you’re not really sure what to do. No worries. I was like you, and I fumbled through it cobbling together a variety of guides and tutorials, and here, centralized in one place, is how I did it. This is the dead simple, option-free way to get something going with your RPi. All you’re going to get from this tutorial is an OS and web server on the device, but you’re not going to have to pick
- The RPi, obviously (pictured)
- A formatted Mini SD card that will act as the hard drive (pictured), or optionally a MicroSD card with a mini adapter. Either way, it needs at least 2 GB of space
- A micro-USB electronic device charger (i.e. an “anything but Apple” cell phone charger) to power the Pi.
- A desktop, Windows computer with either an onboard or connected SD card reader/writer
- An internet connection
- (Optional) HDMI to DVI adapter if you plan to spend a significant amount of time with your RPi plugged into a monitor.
You can probably make it happen without most of these things, but this is what I was working with when I did it, so if you have a Mac or want a different Linux distro on your RPi, this isn’t the tutorial for you.
Linux on the Pi
Here are the steps that I followed:
- First, download the zipped OS, “Raspbian Wheezy” for the RPi at this link, which will actually trigger the download. If that becomes defunct or you want to find it on your own, you can go to the RPi download site.
- Now that you have the OS, you need a means of putting it on the SD card. For that, you’ll need the Win32 Image writer (link triggers actual download of zip) or find the download yourself at their site.
- Plug your SD card into your SD reader/writer.
- Extract the contents of both of the zip files that you downloaded and launch the disk manager utility with administrator rights. If it takes a long time to load, there’s probably a driver issue with your SD card — that happened to me, but the fix was very specific to my hardware and is thus beyond the scope of this tutorial.
- Choose the Wheezy-Raspbian img file and the drive in which your SD card is mounted on your computer (below). For me the only option was the drive with the SD card, but make sure you double check that it’s the right one — I don’t want to be responsible for your frying some drive you need with a Linux install.
- When you’re sure you’re not blowing anything you need away, click “Write,” and then click “OK” when warned.
- The write process will take a while, with specifics depending on your hardware. For me it took about 10 minutes. At the end, a “Write Successful” dialog will appear.
- Pop the SD card out of the computer and put it into the RPi.
- Plug your RPi’s HDMI into a TV (or monitor with the adapter) and plug a USB keyboard and mouse into the RPi.
- Now plug the RPi into power and let it boot up. It should look like a normal Linux boot sequence:
- Once it boots up, you’ll be shown some initial configuration options. I enabled SSH and expanded the root partition to use my entire 8 Gig SD card. Your mileage may vary here, but I bought the SD card just for the Pi and I have no interest in leaving the Pi plugged into my bedroom TV on a permanent basis, preferring to remote in.
- I also enabled booting into desktop, though I may later get rid of that option since the Pi will be headless. From there I selected “Finish” and rebooted. This took a while since it resized the root partition on reboot.
- Once it booted, it booted to a cute little desktop with the RPi logo in the background and you can configure it like any other Linux distro.
- One early thing to note is that the default user/pass is pi/raspberry — this will help if you drop into a console tty. (i.e. you hit ctrl-alt-f4)
- On the desktop, I noted that wheezy ships with WPA-supplicant for wifi config, which is handy if you have a wifi USB dongle, though I did not go this route — I have known much pain from using wpa_supplicant 5-6 years ago with AES before the utility was mature.
- After playing with the RPi desktop a bit, I powered down and disconnected from the TV, setting it up headless in my office, to be accessed via SSH.
- At this point, I tunneled in via SSH and ran an update. I had seen that things weren’t working on the desktop because it needed updating, so, first things first. “sudo apt-get update” did the trick (after about 4 or 5 minutes).
- To put apache on there, I did “sudo apt-get install apache2″. Ah, apt-get, the original app store.
- Finally, if you’re going to have a web server, it makes sense to give it a static IP. There’s nothing specific to Wheezy about this — it’s just standard Linux networking involving modifications to the network/interfaces file.
And, viola! The transformation from RPi in the box it shipped in to little web server is complete.