Re: [libvirt] [PATCH 0/3] add option to keep nvram file on undefine

There is already a patch [1] on this topic with a different approach - keep nvram file by default. There is also some discussion there. To sum up keeping nvram on undefine could be useful in some usecases so there should be an option to do it. On the other hand there is a danger of leaving domain assets after its undefine and unsing them unintentionally on defining domain with the same name. AFAIU keeping nvram by default was motivated by domain disks behaviour. I think there is a difference as libvirt never create disks for domain as opposed to nvram and managed save and without disks domain will not start so user is quite aware of disks files. On the other hand one can start using nvram file solely putting <nvram> in config and managed save is created on daemon shutdown. So user is much less aware of nvram and managed save existence. Thus one can easily mess up by unaware define $name/using/undefine/define $name again usecase. Thus I vote for keeping said assets only if it is specified explicitly so user knows what he is doing. Adding option to undefine is best solution I come up with. The other options are add checks on define or start and both are impossible. Such a check should be done without any extra flags for it to be useful but this way we break existing users. As this a proof of concept this series does not add extra flag for managed save. [1] https://www.redhat.com/archives/libvir-list/2015-February/msg00915.html