Packer

For several years now, I’ve been running all my AWS instances with a recent long-term support edition of Ubuntu server, ZFS as the root file system. Ubuntu 20.04 LTS was released today, so I’ve updated my Packer templates - the original inspiration for the amazon-ebssurrogate builder - to support it!

Ubuntu 20.04 has some nice new features, including:

• ZFS on Linux version 0.8.3,
• Linux Kernel version 5.4, including io_uring and built-in support for WireGuard,
• Up-to-date compiler and runtime packages for a variety of platforms.

Since I last updated these templates, HashiCorp have also added a feature to Packer to allow templates to be authored in HashiCorp Configuration Language v2 instead of JSON.

Last year, I posted about how to build Ubuntu 16.04 AMIs using HashiCorp Packer’s ebs-surrogate builder. Since then Ubuntu 18.04 has been released, and the process has changed a little.

Some recent image building work I was doing required images based on Windows Server. One of my more popular posts, Windows AMIs Without the Tears, detailed the fraught endeavor of making the WinRM management system work for this purpose, but since then Microsoft have substantially improved the situation by committing engineering effort to porting OpenSSH to Windows.

For all applications of importance or significance, we recommend using ZFS. On bare metal servers, ZFS is king of the hill, but on AWS and Linux it is still gaining traction. Data integrity guarantees as well as features such as “instantaneous” snapshots, compression, quotas, and the ability to send/receive datasets make ZFS very compelling. In this post, we’re going to demonstrate how to build from-scratch AMIs booting Ubuntu Linux with a ZFS root file system.

Twice in the last couple of weeks I’ve helped automate build infrastructure in AWS, first for Event Store and then secondly for another company. Both times we got 90% of the way there using great tools like Terraform and Packer, and fell at the last hurdle: how do you build Windows images in an automated fashion (i.e. no point-and-click)?