packer-ubuntu-cloud-image

Build Ubuntu virtual machine images using Packer qemu builder with the Ubuntu Cloud Images as the disk image source. Ubuntu cloud images are conventient to build fast and produce cloud-init friendly images.

Dependencies

• Install Hashicorp Packer
• Install Qemu
• Install a compatible ISO generation tool (xorriso, mkisofs, hdiutil, or oscdimg). See Packer qemu docs for more information.

Building Images

Update the scripts/install.sh script to manage what packages are installed during image provisioning. By default, qemu-guest-agent and docker-ce are installed.

Build Default Ubuntu Version

Install required plugins:

$ packer init ubuntu.pkr.hcl

Run the Packer build. By default an Ubuntu 22.04 (jammy) image is built:

$ packer build ubuntu.pkr.hcl
==> qemu.ubuntu: Retrieving ISO
==> qemu.ubuntu: Trying https://cloud-images.ubuntu.com/jammy/current/jammy-server-cloudimg-amd64.img
...
==> qemu.ubuntu: Gracefully halting virtual machine...
==> qemu.ubuntu: Converting hard drive...
Build 'qemu.ubuntu' finished after 1 minute 56 seconds.

==> Wait completed after 1 minute 56 seconds

==> Builds finished. The artifacts of successful builds are:
--> qemu.ubuntu: VM files in directory: output-jammy

Generated images will be in output-<ubuntu version>/ubuntu-<ubuntu version>.img.

$ ls -lh output-jammy
total 962M
-rw-r--r-- 1 user user 963M Feb  5 14:53 ubuntu-jammy.img

Build Specific Ubuntu Version

Pass a packer variable ubuntu_version to set the Ubuntu cloud image to use as a source. See available versions on the Ubuntu Cloud Images page.

For example, pass -var ubuntu_version=focal to build with the Ubuntu 20.04 "focal" image:

$ packer build -var ubuntu_version=focal ubuntu.pkr.hcl
==> qemu.ubuntu: Retrieving ISO
==> qemu.ubuntu: Trying https://cloud-images.ubuntu.com/focal/current/focal-server-cloudimg-amd64.img
...
==> qemu.ubuntu: Gracefully halting virtual machine...
==> qemu.ubuntu: Converting hard drive...
Build 'qemu.ubuntu' finished after 1 minute 55 seconds.

==> Wait completed after 1 minute 55 seconds

==> Builds finished. The artifacts of successful builds are:
--> qemu.ubuntu: VM files in directory: output-focal

Troubleshooting

Pass or set the environment variable PACKER_LOG=1 to provide additional debug logging output to help troubleshoot build issues.

$ PACKER_LOG=1 packer build ubuntu.pkr.hcl
2023/02/05 14:48:44 [INFO] Packer version: 1.8.5 [go1.19.4 linux amd64]
2023/02/05 14:48:44 [TRACE] discovering plugins in /usr/bin
2023/02/05 14:48:44 [TRACE] discovering plugins in /home/user/.config/packer/plugins
2023/02/05 14:48:44 [TRACE] discovering plugins in .
2023/02/05 14:48:44 [INFO] PACKER_CONFIG env var not set; checking the default config file path
...