I reinstalled my primary laptop (Lenovo x250) about 3 months ago (June 30, 2016), when I got a shiny new SSD, with a fresh Ubuntu 16.04 LTS image.
Just yesterday, I needed to test something in KVM. Something that could only be tested in KVM.
I don't have KVM installed? How is that even possible? I used to be the maintainer of the virtualization stack in Ubuntu (kvm, qemu, libvirt, virt-manager, et al.)! I lived and breathed virtualization on Ubuntu for years...
Alas, it seems that I've use LXD for everything these days! It's built into every Ubuntu 16.04 LTS server, and one 'apt install lxd' away from having it on your desktop. With ZFS, instances start in under 3 seconds. Snapshots, live migration, an image store, a REST API, all built in. Try it out, if you haven't, it's great!
But that's enough of a LXD advertisement...back to the title of the blog post.
Here, I want to download an Ubuntu cloud image, and boot into it. There's one extra step nowadays. You need to create your "user data" and feed it into cloud-init.
First, create a simple text file, called "seed":
Now, generate a "seed.img" disk, like this:
Next, download your image from cloud-images.ubuntu.com:
In the nominal case, you can now just launch KVM, and add your user data as a cdrom disk. When it boots, you can login with "ubuntu" and "passw0rd", which we set in the seed:
Finally, let's enable more bells an whistles, and speed this VM up. Let's give it all 4 CPUs, a healthy 8GB of memory, a virtio disk, and let's port forward ssh to 2222:
And with that, we can how ssh into the VM, with the public SSH key specified in our seed:
Cheers,
:-Dustin