Installation Guidelines: Virtual Machine

The most convenient way to get up and running is to use a pre-configured development kit -- a complete operating system that's been set up to include all the required code and tools, and saved as an image of the system's disk -- and run this "virtual system" (sometimes called an "appliance") in a "virtual machine" (VM). The virtual machine runs as an application on your machine -- the "host" machine -- and emulates a separate computer -- the "guest" machine. You won't have to install anything but the virtual machine directly on your system. (We're including the official virtual machine jargon in case you need to read virtual machine documentation. We'll use "VM" to refer to the guest virtual machine. The virtual machine "manager" will be the tool that is used to configure and start your VM.)

Get the Sahana Eden development kit image

• Download the current virtual machine image. Size is about 400MB.

• The downloaded file is compressed -- uncompress it as follows. (You should end up with a directory with a name like "Eden Dev Env".)
  • On Windows, a good tool for (un)compressing is ​7-Zip.
  • On Linux / Unix, do:
    tar xzf filename.tar.gz
    using the actual downloaded filename in place of filename.tar.gz.

Install VirtualBox

• Download the appropriate ​VirtualBox binary for your system. (You won't need the SDK, and would only need the "extension pack" if you want to use a USB device from your virtual system. You can add it later if so.)

• Run the installer (by whatever means is appropriate for your system).
  • Let it install all features.
  • The installation will temporarily disconnect your machine from the network -- take appropriate action before letting the installer proceed if you are running something that can't tolerate being disconnected.

Import the image into the virtual machine

• Start VirtualBox Manager (or let the installer start it).

• Give VirtualBox Manager the image to run:
  • Select File -> Import Appliance.
  • Click the Choose button. Navigate into the Eden Dev Env directory and select the .ovf file).
  • Click Next (or Open, for a Mac).
  • (Do not uncheck any options on the appliance options form.)
  • Click Import.

Start the virtual machine

On the left side of the VirtualBox Manager GUI, you should see your new "Eden Dev Env" virtual machine.

• Double-click the virtual machine entry to start it.
• The Login screen should appear. User is dev and password is EastOfEden.
• After you're logged in, the Eclipse IDE will start -- ignore it for the moment.

Change your password.

• Start a terminal window by double-clicking the LXTerminal icon.
• To change your password, type passwd and follow the instructions.

Connect to the network

Next tell the VM about your machine's network interface, so the guest can get to the network.

• Scroll down on the right side of VirtualBox Manager until you see Network -- click that.
• If no adapters are enabled, enable adapter 1.
• For "Attached to" select "Bridged Adapter".
• Under that, for "Name", select the appropriate network interface, e.g. wireless if that's what you're using. (Keep this setting in mind -- you may need to change it if you sometimes use a wired network, and sometimes wireless.)

After logging in…

Updating Web2py, Eden, and the operating system

GHC Codeathon participants, take note! You don't need to update anything -- skip this.

The Eden code is updated (much) more frequently than is the VM image, so the Eden branch supplied in the image will be out of date. So, too, will be Web2py and the Linux distribution, but those will typically not need frequent updating. We recommend only updating Eden unless you know that new versions of the others are needed.

Update web2py

On occasion, the latest revision of Web2py is not stable. Check the topic in the #sahana-eden IRC channel on freenode for the latest known-safe revision. To update Web2py to the latest revision:

cd /home/web2py
bzr update

To update to a specific revision, do the following with nnnn replaced by the revision you want.

cd /home/web2py
bzr update -r nnnn

Update Eden

You will almost certainly want the latest revision of Eden.

cd /home/web2py/applications/eden
bzr pull

If, for some reason, you need a specific revision, do the following with nnnn replaced by the revision you want:

cd /home/web2py/applications/eden
bzr pull -r nnn

Optionally update the operating system

Although it's usually good advice to update the operating system and applications to pick up security fixes, updating may lead to incompatibilities with other software, and has been known to render the system unusable. So do the following only if you know there is a security issue, and not when you're in the middle of something critical.
Log in as dev and execute the following:

sudo apt-get update
sudo apt-get upgrade

Eclipse

Some parts of the Eclipse and PyDev configuration need to be done after startup:

• DeveloperGuidelinesEclipse#Configuration

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Notes on the configuration

Which Linux is this?

The virtual machine image is based on a blueprint and is configured to use about 512MB of RAM. The virtual disk is configured to expand to 20GB. The virtual machine is built on ​TurnKey Linux's Core, which in turn is based on Ubuntu 10.04 (Lucid -- the most recent long-term support release). The machine runs ​Shellinabox, ​Webmin, and SSH/sftp as services from startup.

The development environment uses ​LXDE, a lightweight desktop environment.

Bridged networking vs. NAT

There are two options for having the host and guest share the physical interface, NAT or bridged. NAT is less obtrusive but bridged provides more capability to the guest. See this discussion of the ​differences between NAT and bridged modes. The installation procedure shows bridged setup (because everyone who we know who is using VirtualBox is using bridged networking...).

Tools

Several useful tools have been installed:

• Bazaar (bzr) -- revision control system used on Launchpad, where Sahana eden sources are hosted.
• Firefox with Firebug for examining what is sent to the browser, and viewing HTTP messages sent to and from the browser.
• Eclipse with PyDev for editing and debugging Python code.
• Scripts for updating the Eden code and other tools.
• iPython -- a fancier Python command line than the standard. (Note not everyone prefers this.)
• irssi

Notes on using Linux (mainly for non-Linux users)

File locations

Web2py is located in /home/web2py. Eden is located in /home/web2py/applications/eden. Eclipse and PyDev are preconfigured with this information.

The root account

The root account is the privileged user on Linux, but you don't need to log in as root to perform privileged tasks like installing software. You can act as root without knowing the root password with the sudo command -- the dev account has the privilege to use sudo. In a terminal window, to execute a command with root privileges:

sudo command-to-execute-as-root

This will prompt for a password if sudo hasn't been run recently -- it is asking for the current user's password -- here, that's the dev password.

To change passwords after first boot, log in as dev, start a terminal window, and enter the following commands:

sudo passwd root #change root password
passwd #change dev password

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Procedure for making a new virtual machine image

InstallationGuidelinesVirtualMachineMaintenance