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Good afternoon to all!
As I have read, NOVA interacts with QEMU/KVM through libvirt virtualization API. Virtual Machine instances are defined in libvirt by the use of an XML file which lives in /etc/libvirt/qemu/ path of each compute node.

Based on the following Launchpad bug (link below), starting from OpenStack Nova 2013.1 release, let me quote: " There's no reason to ever use the the XML files stored in the instances directory; it is there for operational purposes only." and "This will undo any one-off/by-hand changes in favor of absolute consistency with the database, which is preferred.".

https://bugs.launchpad.net/nova/+bug/1081373

So, the question is simple. What operation to follow in order to permanently change instance metadata by editing this XML file? Or else, edit Nova database records?

Thank you in advance!

Dionisis (Dennis) Drakopoulos
OMP MP SW Engineer/SyVe/Maintenance/SL
MBB OMP MP R&D 14 GR
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