OpenNebula

Ideally during a reload oned would (also) check the config (and all other stuff that is critical to correctly function to ensure uninterrupted operation (parse it, check for valid config and report errors if any).

Use cases:

- During a restart oned is temporarily unavailable. For this brief period of time no cloud services are available. Users cannot login, open a vnc console, etc. If you have made an error in the oned config this downtime period will be prolongued.

- A configuration management solution (CFengine, Puppet, Chef, etc.) can be used to manage the oned.conf configuration file. I.e. it can just try to reload oned and check for errors, and act accordingly.

- Monitoring for correct oned config file. You can make a monitoring check to make sure there are no errors in the config file. And rest assured that if a restart would occur (reboot of the server in case of some server issue) it will work. In order to avoid an actual reload every time this check would be invoked a "--configtest" argument option should be added to oned.