Re: [Engine-devel] Floating Disks implementation in REST-API

> >>> Floating disks should be both in the root context, and also in the VM >>> context for each VM the floating disk is attached to, right? So floating >>> disks would appear 1+N_attach times in the API, once in the root >>> context, and once for each VM they are attached to. >>> >> >> IIUC a floating disk is not associated with the VM in any way, and should >> not appear in that VM's collection of disks. There's a similar feature of >> activate/deactivate disk (http://www.ovirt.org/wiki/Features/HotPlug). >> A deactivated disk is still associated with the VM, and should appear in >> the VM's collection of disks. Perhaps this is the source of confusion. > > No that isn't it. I think have a bit of terminology mismatch. According to: > > http://www.ovirt.org/wiki/Features/DetailedFloatingDisk > > i think your use of the word floating is correct. I got confused as i > thought that any disk could be floating, whether it was attached to 0 > VMs, 1 VM, or 2 or more VMs. > > So before we go further, let's get things straight: > > - disk without any VMs => floating. It appears in the root context. > - disk attached to 1 VM => normal state. It appears in the VM context. I think this type of disk should be shown in both contexts. If a user is looking at http://{host:port}/disks, I think he intuitively expects to see all disks (attached or unattached). A disk will contain reference to the VMs which it is attached to, and thus: - No VM-ids --> floating disk. - One VM-id --> regular disk. - Multiple VM-ids --> shared disk.

> - disk attached to 2 VMs => shared disk. It appears in both VM contexts. > > Is that correct? > > Also can someone explain on how floating and shared disks are actually > implemented in the BE? I imagine it's one of two ways: > > => The BE keep a global list of disks, each disk with zero or more > references to a VM. > => The BE keeps a special "floating" state independent of the number > of VMs that it is attached to. > > Thanks, > Geert _______________________________________________ Engine-devel mailing list Engine-devel(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel