Yesterday I announced the availability of updated Ubuntu images on EC2 for 10.04 LTS (Lucid Lynx).
This post is mainly to mirror that one to a possibly wider audience, but also to go into more detail on the key change in these images:
You can now upgrade the kernel inside your 10.04 based EC2 image by running 'apt-get update && apt-get dist-upgrade && reboot!
Now, for a little more detail on that.
Around the time that 10.04 released, or shortly there after, Amazon released a new feature of EC2 as "Use Your Own Kernel with Amazon EC2". What this really meant was that there were now "kernels" on EC2 that were really versions of grub. By selecting this kernel, and providing a /boot/grub/menu.lst inside your image, the instance would be in control of the kernel booted. Previously, the loading of a kernel was done by the xen hypervisor, and could not be changed at all for a instance-store image, and only non-trivially for an EBS-root instance
Yes, you read that right, midway through the year of 2010 you were able to change the kernel that you were running in an EC2 instance with a software update and a reboot.
We took advantage of this support in our 10.10 images, but for many people, only LTS (Long Term Support) releases are interesting. So, to satisfy those people, we've brought the function into our 10.04 images.
If you're using our images, or have rebundled an image starting from them, I *strongly* suggest updating to the 20110201.1 images or anything later. You'll want to do that because
- You can receive kernel upgrades as normal software upgrades to your running instance.
- This is by far the most supportable route for upgrade from 10.04 to our next LTS (12.04). If your instance is not using the pv-grub kernel, and you want to upgrade to a newer release, you will have to upgrade, shutdown the instance, modify the associated kernel, and start up the instance. That is both more painful, and will result in larger downtime.
So, in short, grab our new images!