Ubuntu 10.04 Lucid is expected to be released this Thursday (April 29, 2010). This is the first LTS (long term support) release since Ubuntu 8.04 Hardy, which has itself been a stable and reliable server platform for years both inside and outside of Amazon EC2.
If you’re starting a new server project on EC2, Ubuntu 10.04 Lucid would be a great release to start with. It will be supported for five years with security patches and major bug fixes.
If you are already running a different Ubuntu release on EC2, you should consider planning an upgrade to Lucid. Here are my thoughts for each release you might currently be running on EC2:
Ubuntu 8.04 Hardy should continue to be fairly stable for a while, though there does not appear to be a lot of EC2-specific development being applied to the AMIs, so you may want to upgrade to Lucid LTS at your leisure. You will probably want to start new instances, though with Scott’s comment below, it might be possible to upgrade in-place on EBS boot from Hardy to Lucid. If you happen to still be running the Alestic Hardy AMIs, you should at least consider upgrading to the Hardy AMIs published by Canonical and listed at the top of Alestic.com.
Ubuntu 8.10 Intrepid has reached its end of life and should no longer be used on EC2. If you are still running Intrepid, you should immediately start upgrading to Karmic or Intrepid through starting new instances.
Ubuntu 9.04 Jaunty on EC2 is still running on an old Fedora 8 kernel and is not supported by Ubuntu. I’ve been recommending an upgrade from Jaunty for a while. I continue to recommend upgrading to Karmic (if you want something that has been tested in production for a while) or Lucid (once you’re comfortable with the release).
Ubuntu 9.10 Karmic still works great on EC2, though there are a couple bothersome bugs (like hostname reset on reboot) that should be fixed by upgrading to Lucid. If you are running an EBS boot Karmic instance, then it is possible to upgrade in place, but it’s also fine to simply start new instances.
Ubuntu 10.04 Lucid pre-release instances should be upgraded to the released version. If you are running EBS boot Lucid, then it is possible to upgrade in place even if there are a newer kernel and ramdisk.
Scott Moser of Canonical has laid out the steps necessary to upgrade an EC2 instance in place without having to start a new EC2 instance. This only works for instances that are currently running an EBS boot pre-release Lucid AMI or an EBS boot 9.10 Karmic AMI. All other servers will need to be upgraded by starting new Lucid instances to replace the old instances. Fortunately, EC2 makes that easy.
In fact, EC2 makes starting new replacement instances so convenient, I would recommend following that procedure in most cases even if you think you can upgrade a server in place. If you encounter any troubles in getting your service to run on Lucid, running a new instance makes it straight forward to fall back to the old server. And, once you are happy with the new server, make it your production system, terminate the old one and don’t look back.
Welcome to the new world of cloud computing where you can instantly acquire and discard server hardware for mere dollars without worrying about large investments, complicated provisioning, and long term support costs.
I will add the new Lucid AMI ids to the table at the top of Alestic.com as soon as I get word that they are ready.