One-context vs cloud-init


(Gui||aume) #1

Just wondering why not always using cloud-init instead of one-context ? Does one-context scripts do things that cloud-init doesn’t?

Thank you.


(Ruben S. Montero) #2

Hi Guillaume,

This has been a long discussion among the team. We’ve developed data
sources for cloud-init and make it functional with OpenNebula:

http://cloudinit.readthedocs.org/en/latest/topics/datasources.html#opennebula

However, the cloud-init community is not accepting patches and
contributions to the desirable pace, and it quickly lags behind OpenNebula
develoments.

We found that OpenNebula context is much simpler, easier to deploy and
easier to evolve and introduce new features. You need to install the
packages, though… Although we do not find any fun in reinventing the
wheel, depending on cloud-init was seriously impacting “user-experience”.

Feature-wise I don’t think there are more features in any of the two.

Cheers


(Gui||aume) #3

Thank you for your explanation.

I would like to prepare an Oracle Database image based on the CentOS 7.1 one-marketplace image and I would like to make sure that all one-context scripts will re-run after the new image is started.

Based on this procedure, should only have to remove all one-context* packages and reinstall them?

For cloud-init, deleting all files in the /var/lib/cloud/instance/sem/ directory do the job.

Thanks again and happy new year!

UPDATE
Just realized that the one-context scripts are executed at each boot. My bad.


(Sergio) #4

So @ruben cloud init isn’t needed to contextualize in OpenNebula? Are there some OpenNebula features that require cloud init to work? The docs says it’s needed to install.


(Javi Fontán) #5

cloud-init is not supported. In fact it can cause problems if one context packages are also installed. Can you point us where it says cloud-init is needed? Thanks


(José M. de la Fé) #6

@jfontan, cloud-init isn’t a requirement to contextualize a VM but there’s no warning to disable it (or uninstall it) either. A lot of pre-configured images have the cloud-init services activated by default and if it can cause problems, it would be nice if the documentation says so.


(Sergio) #7

Sorry I confused cloud-init for cloud-utils :pensive:


(José M. de la Fé) #8

@jfontan I’ve checked the documentation for OpenNebula 5.4 and I saw the step to remove cloud-init package. Nice! :slight_smile: :+1: Thanks


(Javi Fontán) #9

Back again from the dungeon after the release :sweat_smile:

Most probably the confusion comes because we did support cloud-init in the past. We may have to add a big warning in the documentation stating that.