Re: [libvirt] [PATCH v3 4/7] qemu: Translate the iscsi pool/volume disk source

Il 24/07/2013 12:31, Daniel P. Berrange ha scritto: > On Wed, Jul 24, 2013 at 12:25:17PM +0200, Paolo Bonzini wrote: >> Il 24/07/2013 11:54, Daniel P. Berrange ha scritto: >>>> but anyway, we provide good enough documentations, so if one wants to >>>> use "direct" mode, he can still change the xml to use it, any big problems >>>> here? though defaulting to "direct" is more convenient for these users. >>> >>> Defaulting to "direct" is *NOT* more convenient for all users, only >>> those who happen to have a new enough QEMU, from a vendor who actually >>> decided to compile in the iSCSI support. If they're lacking such a QEMU >>> then the "direct" mode will prevent the default config from even starting. >>> This can never be an acceptable default choice. mode="host", while it huas >>> some limitations in features, is the only option that is capable of working >>> with any QEMU >> >> s/limitations in features/possibility of wreaking havoc to clusters/ > > This isn't a new issue. People have been using KVM with iSCSI in host > mode for as long as KVM has existed and the sky hasn't fallen in > clusters. As long as it is a documented limitation, that admins can > address with a config setting if desired, I don't see that this is > suddenly something we must fix at the cost of breaking the default > config for QEMU's without iSCSI support. Understood, that's why I suggested not having a default config at all for type='lun' devices.

Also, can libvirt at least detect using a volume on a pool that wasn't started, and fail unless mode='direct'?