WARNING!
Though most Ubuntu 9.04 Jaunty systems can upgrade to 9.10 Karmic in place, this is not possible on EC2 and should not be attempted. If you do try this, your system will become unusable on reboot and there will be no recovery and no access to any of the data on the boot disk or ephemeral storage.
Here’s why:
Ubuntu 9.10 Karmic has a version of udev which requires a newer kernel than you would be running for Ubuntu 9.04 Jaunty (especially on EC2).
You cannot upgrade the kernel used by a running instance on Amazon EC2 (not even rebooting).
When an EC2 instance cannot boot (as in the case of the udev/kernel mismatch) your only option is to terminate it, losing the local storage.
How To Upgrade
In order to upgrade to Karmic you will need to start a new EC2 instance running a fresh copy of the appropriate Karmic AMI. I post the latest AMI ids for Karmic in the second table on http://alestic.com/.
Keep your old instance(s) running while you configure and test the new Karmic instances. EC2 makes it easy to have multiple sets of servers running in parallel instead of upgrading in place. When you are confident your new servers are functioning properly, you can discard the old ones.
The Ubuntu 9.10 Karmic AMIs released by Canonical have a number of differences from the community Ubuntu AMIs which have been published on http://alestic.com.
One of the biggest differences is that you will ssh to ubuntu@ instead of to root@ on your instance. You can then sudo to perform commands as the root user. Back in April I wrote a guide about Using sudo, ssh, rsync on the Official Ubuntu Images for EC2.
The Ubuntu server team has put a lot of work into making Ubuntu 9.10 Karmic function beautifully on Amazon EC2 and it’s been a pleasure to have a small part in the process. I’m already using the Karmic AMIs on EC2 for one of my production processes. Please give these AMIs a spin and give feedback.
Eric-
I noticed you retweeted somebody the other day claiming that Jaunty was "kicking Hardy's a**." And now I see you're using Karmic for at least one production scenario.
I'm running 2 medium instances on Alestic's Hardy: 1 for a basic webserver (Apache and Nginx) and 1 for MySQL. They boot up fast, and your latest fancy auto-snapshot stuff seems to be working great (funny that they released DBS just a week later... oh well).
So the question is, am I missing out on something fantastic that's in Jaunty or Karmic? I'd love your opinion!
Thanks,
-Jed
Jed: I run Jaunty on my laptop and experience a number of very serious very frequent problems (freezing, cold shutdowns, wireless network dropping out). I run Hardy on most of my EC2 servers and am very happy with its stability. I plan to upgrade to Karmic for my desktop and Lucid (the next LTS release in 10.04) for my servers.
For folks who are just starting out on EC2, I recommend trying Karmic first to see if it meets your needs given that Karmic has a modern Ubuntu kernel and is well maintained.
Great, thanks for the response Eric. Sticking with Hardy until Lucid sounds like a great idea (at least for my production servers).
Keep up all the great work! As several others have mentioned, you make it so that hacks like me can actually run a pretty decent operation through AWS.
Eric,
we have been very pleased with your 9.04 Ubuntu AMIs; we are using them on all of our test and production servers here at Extrabux at the moment. Are you planning on releasing 9.10 AMIs soon or would you recommend that we start using the Canonical AMIs instead? I'm a bit hesitant to make that switch since all of our tools and automation has been designed around the Alestic AMIs and it looks like the transition to the Canonical AMIs could introduce the need for tweaks that require more extensive testing.
Patrick: Glad to hear that the AMIs have been working for you. I have no plans to release base Karmic server AMIs at this time. Instead I have applied my efforts towards working with the Ubuntu server team in the development of the excellent Karmic AMIs that are now available. A big part of my work was to help make sure that the transition from the existing AMIs to the new AMIs would be as smooth as possible.
Eric,
thanks a lot for your reply. Do you have a post anywhere or could you give us an overview of the most important differences between your alestic AMIs and the Karmic AMIs that would affect integration with a current production system in particular as they relate to startup scripts, authentication, installed base packages, interaction with EC2, etc? (I know that the Karmic AMIs require you to log in as ubuntu instead of root, but do they handle startup scripts in the same way?)
Thanks!
--Patrick
http://www.extrabux.com
Patrick: Here's an overview of the differences I know about:
http://alestic.com/2009/04/official-ubuntu-ec2
Please post comments there if you find more.