I've read a couple of articles that Eucalyptus doesn't support bootable EBS yet. This is a problem since you can't make a backup form an instance like you a able on Amazon cloud or Rack Space Cloud.
If you ever reboot the physical Ecalyptus sever that's running the node controller the instance is gone along with all your settings. Are there any alternatives to Eucalyptus or is just the only game in town when it comes to open source cloud?
as mentioned by kim0, Eucalyptus 3 will have boot from EBS. Another solution which you can already employ with 2.0 is mentioned here http://open.eucalyptus.com/wiki/install-service-ebs-volume. For example support.eucalyptus.com runs this way http://open.eucalyptus.com/learn/first-service-in-the-cloud.
cheers graziano
Here are 3 open source cloud projects:
If you are looking for free vs open source and have a small cluster. Nimbula Director is a commerical offering which is free for up to 40 cores.
Bootable EBS is coming in Eucalyptus v3.0 which should launch in a few months. OpenStack is shipping with Ubuntu 11.04 and should be a respectable alternative
You should checkout CloudStack - it's the IaaS platform used by Zynga, Godaddy, Edmunds.com and about 60 more large clouds. And it's GPLv3.