The Lightsail installation script has been updated for compatibility with Ubuntu 20.04 LTS. (Mostly this was just removing the dependency we had on Docker’s personal repo now that Ubuntu releases have caught up to the functionality we needed from Docker.)
From the AWS package perspective, Express Plus should take advantage of this immediately, since it uses Lightsail launching techniques; Express and Standard will require additional work before they’re ready.
Is there a procedure for upgrading an existing production Express Plus instance installed using the previous iteration of the Lightsail script? (16.04->20.04)
Snapshot your volume first. This may not be as clean as you’d hope.
The problem here is that Lightsail had opinions about the Docker versions it wanted available, and stock Ubuntu 16 couldn’t meet those needs, so we reached out to Docker’s own repo and got the versions we wanted ourselves. I think it also specifically picked up a docker-compose from another source as well?
Upgrading to Ubuntu 18 or 20 may or may not involve version conflicts with the trans-distro packages and I don’t fully understand how those will end up shaking out. I think you’ll eventually come to a conclusion – possibly ripping Docker out by the roots and putting 20’s preferred versions in place – but I can’t guarantee how well that’ll work with the docker-compose we used, so you might end up having to take additional steps to manipulate the images and docker-compose might not cleanly work on the images a second time.
This may be easier than I hope! Do not depend on this, and see that you have a full backup copy of your instance’s EBS volume before you continue.
Then I’m happy to have supplied the expected amount of doom. Going forward, we don’t expect this issue to be repeated – the refresh to 20 simplified things and pared down the requirements. When the day comes to jump to 22 or 24, I’d still say you should snapshot a backup but it should be a by-the-numbers affair.