[Engine-devel] Requirements for Aeolus instance data injection.

[jvlcek]

Itamar,

The below, provided by David Lutterkort, is a good description
of the requirements for Aeolus instance data injection.

Joe VLcek

         RHEV-M shall accept a small blob of data as part of the 'start
         VM' action. That data has to be placed somewhere where the VM
         can easily and securely access it. The data must only be visible
         to the VM it is intended for.

         Possibilities for where to put the data include placing it into
         a file on a virtual floppy or CD-ROM that the instance can
         mount, or posting it on a webserver that only the instance has
         access to (cf. EC2's handling of userData for the RunInstances
         call)

         The size limitation for the amount of data shouldn't be kept
         artificially low, but if there are important reasons to make it
         this small 1k would certainly suffice.

         In practical terms, the blob of data should be passed to the
         'start VM' call base64 encoded, and RHEV-M should decode it just
         before putting it into its proper place.