Try running a VM on a low space storage domain. I get an can't do action, but nothing on the event log. This is getting even more strange, because in this particular case, sometimes I might be able to run a vm, but a vm from pool never (i guess because of the snapshot...) - in this case a more informative message should be displayed.
CanDoAction prevents the action from happening interactivly to the user - I'm pretty sure it never gets logged in the audit log? please fix bug description if this is correct. for the other use case: which message are you getting, what exact message do you expected?
something like: "Failed to run VM <name> due to insufficient available storage"
http://gerrit.ovirt.org/7929
http://gerrit.ovirt.org/gitweb?p=ovirt-engine.git;a=commit;h=e8bc12feec78371f9769842f61c55138e943a566
fixed. getting the following error: "Error while executing action: Cannot run VM. Low disk space on relevant Storage Domain".