Hi Run, not sure what you mean (I did not quite understand your explanation) - but here is an exercise from my side (just done it):
https://pasteboard.co/HOowNao.png Check the image - explanation below: Centos55 minimal (builtin) template, spin new VM: --- new volume created with UUID/PATH (name on NFS files system): 021e8602-235b-4e0d-b9e4-04f0ff46399f --it's backing file: backing file: /mnt/63a3ae7b-9ea9-3884-a772-1ea939ef6ec3/93682641-e7f6-11e8-8f64-089e01d943be Create snapshots via GUI - there is qcow2 snapshots created, whole snapshot copied over (converted via qemu-img - "ps aux | grep qemu-img") tool to Secondary NFS Storage - and snapshot REMOVED from original volume on Primary NFS Storage (qemu-img snapshot -l 021e8602-235b-4e0d-b9e4-04f0ff46399f shows zero snaps after ACS has finished creating snapshots) Volume still points to it's backing file - no changes so far (as expected) Then I restore volume from snapshots. CloudStack will (my conclusions from the exercise), remove original volume on NFS Primary Storage (021e8602-235b-4e0d-b9e4-04f0ff46399f), then it will copy back (convert via qemu-img) a qcow2 file from Secondary Storage back to Primary Storage - but it will use SAME NAME, so you again see 021e8602-235b-4e0d-b9e4-04f0ff46399f on your NFS mount point. This time when you check the image with qemu-img info - it will show it has NO backing file at all - since it's brand new volume/qcow2 image created (as a copy fom Secondary Storage) that is how it works I assume the template will be again cleaned-up/removed from Primary Storage if no other VMs/volume use it as it's backing (parent) image. Makes sense ? Cheers On Thu, 22 Nov 2018 at 21:18, ran huang <[email protected]> wrote: > Thanks Andrija, just tested myself with expunge and works as expected. > > However, for KVM, when I revert a qcow disk from snapshot, which removes > the backing chain to template, the template will not be removed. > > So it seems like despite the qcow disk is no longer backed by the > template, the template will still consider the disk as its children in > this case(revert from snapshot). > > regards, > Ran > > On 11/19/2018 10:43 AM, Andrija Panic wrote: > > new template, deployed new VM, destroyed VM (with Exunge option)... > > > > up to 120sec later... (storage.cleanup.interval=120 sec, global config > > option) > > > > 2018-11-19 19:35:59,525 DEBUGStorage pool garbage collector found 1 > > templates to clean up in storage pool: Primary-storage - NFS > > 2018-11-19 19:35:59,525 DEBUG [c.c.s.StorageManagerImpl] > > (StorageManager-Scavenger-1:ctx-2c88c8e0) (logid:040f4ad1) Storage pool > > garbage collector has marked template with ID: 219 on pool 4 for garbage > > collection > > > > Another 120sec later... (storage.cleanup.delay=120sec) > > > > 2018-11-19 19:37:59,598 DEBUG [c.c.s.StorageManagerImpl] > > (StorageManager-Scavenger-2:ctx-f9dd338d) (logid:9ae40975) Storage pool > > garbage collector found 1 templates to clean up in storage pool: > > Primary-storage - NFS > > ... > > 2018-11-19 19:37:59,638 DEBUG [c.c.t.TemplateManagerImpl] > > (StorageManager-Scavenger-2:ctx-f9dd338d) (logid:9ae40975) Evicting > > TmplPool[37-219-4-563ea0f5-5164-4ac4-a183-728f418269b7] > > 2018-11-19 19:37:59,643 DEBUG [c.c.h.o.r.Ovm3HypervisorGuru] > > (StorageManager-Scavenger-2:ctx-f9dd338d) (logid:9ae40975) > > getCommandHostDelegation: class > com.cloud.agent.api.storage.DestroyCommand > > ... > > 2018-11-19 19:37:59,665 DEBUG [c.c.t.TemplateManagerImpl] > > (StorageManager-Scavenger-2:ctx-f9dd338d) (logid:9ae40975) Successfully > > evicted template andrija-test-tmpl from storage pool null > > > > template "andrija-test-tmpl" deleted... > > > > Hope that helps Run. > > > > Cheers > > Andrija > > > > On Mon, 19 Nov 2018 at 19:11, Andrija Panic <[email protected]> > wrote: > > > >> True (at least I'm sure for SolidFire) - but I believe in general also > >> (will test this now...) > >> > >> On Mon, 19 Nov 2018 at 18:51, Dag Sonstebo <[email protected]> > >> wrote: > >> > >>> Developers please correct me... but as far as I remember there is a > >>> garbage collector which does remove the templates from primary storage > once > >>> they are not needed (i.e. have no more "child VMs"). This is > controlled by > >>> the global setting "storage.template.cleanup.enabled". > >>> > >>> Regards, > >>> Dag Sonstebo > >>> Cloud Architect > >>> ShapeBlue > >>> > >>> > >>> On 16/11/2018, 22:51, "ran huang" <[email protected]> wrote: > >>> > >>> Hi Andrija, > >>> > >>> Thanks for the clarification and quick response > >>> > >>> regards, > >>> Ran > >>> > >>> On 11/16/2018 02:15 PM, Andrija Panic wrote: > >>> > Hi Ran, > >>> > > >>> > templates stays on Primary Storage "forever", at least for NFS > >>> (they are > >>> > moved from Secondary to Primary when you deploy a very first VM > from > >>> > specific template). All VMs have this templates qcow2 as baking > >>> (parent) > >>> > image. > >>> > > >>> > This template is a qcow2 copy of a file from Secondary Storage - > >>> and is > >>> > considered a "parent" image, from which all child images (VM > >>> volumes) are > >>> > created - as you stated baking file (qcow linked clones, in > official > >>> > terminology) > >>> > > >>> > you can have i.e. 100 VMs all linking (having it's backing > file...) > >>> to a > >>> > template qcow2 file. > >>> > So in other words, it's not supposed to be removed. > >>> > > >>> > Does this make sense? > >>> > > >>> > Cheers > >>> > > >>> > > >>> > > >>> > >>> [email protected] > >>> www.shapeblue.com > >>> Amadeus House, Floral Street, London WC2E 9DPUK > >>> @shapeblue > >>> > >>> > >>> > >>>> On Fri, 16 Nov 2018 at 22:38, ran huang <[email protected]> > wrote: > >>> > > >>> >> Greetings All, > >>> >> > >>> >> For qcow2 format images, when creating a new VM in KVM, the > >>> template > >>> >> image is copied from secondary storage to primary storage, and > the > >>> root > >>> >> volume image is created with the template image as a backing > file. > >>> >> > >>> >> But when I break this backing chain on primary(expunge VM or > >>> revert to a > >>> >> snapshot previously created on the root volume image), the > template > >>> >> image is not deleted. > >>> >> > >>> >> Might I ask how is the template image going to be cleaned from > the > >>> >> primary storage? > >>> >> > >>> >> > >>> >> addendum: > >>> >> CS ver 4.9.2 on CentOS 7.2 > >>> >> > >>> >> regards, > >>> >> Ran > >>> >> > >>> > > >>> > >>> > >>> > >>> > >> -- > >> > >> Andrija Panić > >> > > > > -- Andrija Panić
