Date: Fri, 31 Jan 2014 11:42:47 -0200 From: Daniel H Barboza <danielhb@linux.vnet.ibm.com> To: kimchi-devel@ovirt.org Subject: [Kimchi-devel] RFC: "Add disk to existing logical storage pool" Message-ID: <52EBA857.2020302@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hello!

I am almost delivering a first version of this feature but now I am having doubts in how it might work or not.

My implementation would use vgextend and add a disk to an existing LVM pool. The question is that, in this process, all existing data in the added partition will be deleted. Is this ok? We can warn the user about it, of course. But I am not sure if this is the intended design.

I've spoken with Aline a while ago and she agreed that the implementation would function similar to what we have today when creating a new LVM pool. We simply "do not care" about the potential data loss when adding the disk to an existing pool.

Any thoughts?

Certainly if we are going to trash data, we do need to warn the user and make sure they want to proceed... I don't think that is necessarily bad, should be expected for knowledgable admin... Not sure there's an easy answer for add w/o loosing data (well certainly backup/restore after) Primary use case driving this was really the case of adding a new physical disk to system and then add this to the storage pool.. I guess someone could want to take an in use disk from some other system, or elsewhere on the same system, and want ot add that to the pool, thinking that they could still use what was already on there... At this point, I think we stick to KISS... maybe we include the warning/caveat in the Help page for this as well...

thanks!

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Cheers, Frank ----------------------------------------------------------------------------------------------------------------------- Frank Novak ( 诺帆 nuò、fān ) STSM, SCEM Open Hypervisor IBM Linux Technology Center US: fnovak@us.ibm.com ; Notes: Frank Novak/Watson/IBM @IBMUS cell : 919-671-7966 -------------------------------------------------------------------------------------------------------------------------