Announcing Devops Katas

The best way to learn a new tool is to use it. In the development world, there are hundreds of short exercises called katas specifically for this. They're designed to take anywhere from 1-4 hours and help you learn a new language, a new technique, a new library, etc. You go through the process of writing tests, writing code, and seeing something at the end.

One thing that distinguishes good katas is the framework. There's a place you go to with all the files necessary to write tests and write code already in place. The only things missing are the tests and the code. You can focus on the problem at hand instead of the formalities necessary to do a good job. For example:

• http://cyber-dojo.org/
• http://www.butunclebob.com/ArticleS.UncleBob.TheBowlingGameKata

For devops, even though we have more tools, we haven't had anything resembling a kata. Instead, we have things like:

• https://github.com/devtoprod/devopskatas
• http://devopsy.com/blog/2013/08/16/devops-kata-single-line-of-code/

These aren't bad. It's very helpful to have a focused exercise to work with. Except, I can't share my work with you. You can't ask me questions. We can't build on this exercise together. The bowling kata, FizzBuzz, roman numerals - these are all well-known and understood exercises from the development world, regardless of the language you work in.

In that vein, I'm releasing "proper" devops katas at https://github.com/greenfishbluefish/devops-katas. These katas have a Vagrant and Serverspec framework to work within, giving the user the ability to do proper TDD in devops. I'll be releasing at least one/month and would love to get feedback on the next one to do.

Vagrant on Hyper-V: A crazy journey

I love Vagrant. It is the most important devops tool, period. Frankly, far more important than Docker. I use Vagrant with Virtualbox, AWS, Azure, VSphere ... with pretty much every virtualization environment in the world. (Except Docker.)

Funnily enough, it was when I started to heavily use Docker (for SimsLoader) and upgrading one of my laptops to Windows 10 that led me to using Vagrant with Hyper-V. Hyper-V is really cool. Docker runs "natively" under it and it's fast. Really fast.

Unfortunately, Microsoft's work to get all their cool stuff to function with all the opensource tools the Linux ecology has been working with for years. There have been a few posts on this, but they weren't sufficient or complete for me to get up and running.

So, this post is to track and list all the necessary steps to be successful with Vagrant and Hyper-V. These steps have been validated in Windows 10. They may work in Windows 8.1 - if they do, could someone tell me?

Also, if you have cool Powershell scripts to do any of these manual steps, please let me know. Ideally, there's a script that does the "only Once" stuff and a script that does the "Occasionally" stuff.

Stuff you do only Once

Enable Hyper-V

This enables the Hyper-V virtualization provider.

1. Launch "Turn Windows features on or off"
2. Scroll down to select "Hyper-V"
3. Reboot

If you installed the "native" Docker, then you've probably already done this step.

Note: This will disable Virtualbox and all other virtualization providers. To re-enable them, reverse these steps and reboot.

Create a virtual switch

This provides the basis for networking within Hyper-V. Unlike Virtualbox, Hyper-V doesn't auto-create networks for you.

1. Launch "Hyper-V Manager"
2. Click on "Virtual Switch Manager..." (right-hand side)
3. Select "Internal"
4. Click on "Create Virtual Switch"
5. Name the switch "Shared"
6. Select the "Internal Network" radio button
7. Click "Ok"
8. Exit the "Hyper-V Manager" window

Connect the virtual switch to an existing network

This is required if you want your Vagrant-launched VM to get a DHCP-assigned IP address. Again, unlike Virtualbox, Hyper-V networks don't auto-allocate IP addresses.

1. Go to "Control Panel > Network and Internet > Network Connections"
2. Select a network connection with Internet (likely your Wireless)
3. Right-click, select "Properties"
4. Select the "Sharing" tab
5. Click the "Allow other network users to connect through this computer's Internet connection"
6. Select "vEthernet (Shared)"
7. Click "Ok"
8. Exit the "Network Connections" window

Disable SMB idle disconnects

Again, unlike Virtualbox, Hyper-V doesn't provide a file-sharing mechanism. (Granted, vboxfs isn't the greatest, but at least it's immediately functional). So, Vagrant uses SMB sharing. By default, Windows hosts will disconnect the SMB connection if it's idle for too long, which requires you to reboot your VM to reconnect the shared folder.

1. In an administrative powershell, run "net config server /autodisconnect:-1"

Note: this may or may not be what you want to do for other purposes, particularly if you use SMB for other purposes.

Stuff you will have to do occasionally

Resharing the network with your virtual switch

If your internet-enabled network changes, you will need to attach your virtual switch to it. For example, if you switch from wireless to wired.

If your sharing network changes, you will need to reconnect your virtual switch. For example, if you go from home to work or work to Starbucks.

I haven't experienced any problems if I put my laptop to sleep, but awaken onto the same network, but that is also a possible time you may have to reshare your network.

Stuff you will have to do all the time

Launching a VM

1. Open a terminal with administrative privileges. (Hyper-V requires this.)
2. "vagrant up"
3. You will be asked for your windows username/password to mount shared folders.
• Make sure it's the Windows username/password
• Depending on how your laptop is setup, you may or may not have to add a domain to that. (mmouse vs. mmouse@disney)

Additional Documentation

• https://www.vagrantup.com/docs/hyperv/
• https://www.vagrantup.com/docs/hyperv/configuration.html
• https://www.vagrantup.com/docs/synced-folders/smb.html