Thanks for the answer. May I ask why are there some instances that do have a golden image and some that do not?
All the instances come from a template so I wonder why this varies. Also why would the golden image be deleted by the Cloudstack scavenger? I have an Instance failing to boot because it's backing file was deleted by the scavenger. Thanks, On Mon, Apr 23, 2018 at 4:43 AM, Andrija Panic <[email protected]> wrote: > As Ivan explained, when there is brand new template used, ACS will copy it > from Secondary Storage to Primary Storage, this image will become "parent" > / backing / gold image, and is locked as Read Only. Any new VM will have > it's volume "linked" as child image to this parent image. > This is done to > > 1) Save space (imagine 100GB template), and you deploy 100 VMs = maybe > 101GB totally used really...(until you write some new data - it is written > to child images) vs 10000GB if it would be separate images. > > 2) This also brings some performance benefits, since you read from 1 x > 100GB image, not from 100x 100GB images... > > Cheers > > > On 23 April 2018 at 03:59, Ivan Kudryavtsev <[email protected]> > wrote: > > > Hi. > > > > When you create a VM from a template then ACS doesn't copy the template > to > > a new root image, but creates it thin, pointing the volume to the > template > > as a backing store device. > > > > пн, 23 апр. 2018 г., 8:16 Felipe Arturo Polanco < > [email protected] > > >: > > > > > Hello, > > > > > > I am seeing a behavior that I would like to ask about. > > > > > > I have some instances that instead of having a normal qcow2 disk file, > > have > > > a qcow2 file that points to another backing store file. > > > > > > eg: > > > > > > <disk type='file' device='disk'> > > > <driver name='qemu' type='qcow2' cache='none'/> > > > <source file='/mnt/ps4/c6a79f0b-60b2-419c-98af-6ae854f88ad1'/> > > > <backingStore type='file' index='1'> > > > <format type='raw'/> > > > <source file='/mnt/ps4/ddc78c68-47b2-43ef-9109-4c91ebb8bda5'/> > > > <backingStore/> > > > </backingStore> > > > <target dev='vda' bus='virtio'/> > > > <serial>c6a79f0b60b2419c98af</serial> > > > <alias name='virtio-disk0'/> > > > <address type='pci' domain='0x0000' bus='0x00' slot='0x04' > > > function='0x0'/> > > > </disk> > > > > > > I am reading online that this is seen when there is a snapshot of > another > > > disk file, but I have no snapshots, just a regular Linux server that I > > > created through the Cloudstack UI. > > > > > > Any idea of why this would happen? Not all Instances have this backing > > > storage file. > > > > > > Thanks, > > > > > > > > > -- > > Andrija Panić >
