EBS-backed Sierra Instances
We’ve begun experimenting with the creation of Sierra AMIs using Amazon’s new EBS-backed AMI machinery, which allows one to store an AMI’s root device on an EBS volume rather than in bundled format on S3.
Right now, there seems to be little useful Amazon documentation on EBS-backed AMIs; the information necessary to attempt this experiment was gathered from several blog posts. Sierra is based on custom, internally built CentOS 5.3 AMIs; since none of the posts I found were CentOS-specific, some twiddling and guesswork was involved in getting a basic EBS Sierra instance started. However, this particular blog was pretty good: http://www.elastician.com/2009/12/creating-ebs-backed-ami-from-s3-backed.html.
Currently, Sierra AMIs are stored using the original S3-backed approach; Amazon’s new EBS-AMI support provides some advantages that might prove compelling enough to move our current infrastructure over:
- Since the instance root device lives on EBS, we don’t really need (at least at this stage) to create/attach additional volumes to hold the software and data. A single EBS-backed AMI can be up to 1TB in size. Of course, additional volumes can be attached if necessary.
- Startups are much quicker.
- One can “stop” an instance using the new api; this halts the machine without terminating it, and AWS charges stop accumulating at this point. One can restart the instance later without having to re-initialize stored data.
We’ll be continuing our experiments in the coming weeks, as we learn more about this latest AWS feature.
This entry was posted on Monday, January 18th, 2010 at 3:02 pm and is filed under SaffronSierra. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
Leave a Reply
