Bug 1719755

Summary:	[RHOSP 14] Create new image volume cache entry when cloning fails
Product:	Red Hat OpenStack	Reporter:	Pablo Caruana <pcaruana>
Component:	openstack-cinder	Assignee:	Pablo Caruana <pcaruana>
Status:	CLOSED ERRATA	QA Contact:	Tzach Shefi <tshefi>
Severity:	medium	Docs Contact:	Tana <tberry>
Priority:	medium
Version:	14.0 (Rocky)	CC:	pcaruana, rheslop, tkajinam, tshefi
Target Milestone:	---	Keywords:	Triaged, ZStream
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	openstack-cinder-13.0.5-4.el7ost	Doc Type:	Bug Fix
Doc Text:	With this patch, a new Image cache entry is created when cloning an existing entry fails, as can happen when a cached volume reaches its snapshot limit. This allows the user to maintain the performance advantages of having the image cache.	Story Points:	---
Clone Of:	1717727	Environment:
Last Closed:	2019-09-03 15:22:23 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	1717727

Description Pablo Caruana 2019-06-12 13:24:40 UTC

+++ This bug was initially created as a clone of Bug #1717727 +++

Description of problem:

When  enabling image cache feature in cinder, cinder create an image cache volume in storage and create a volume by cloning that image cache volume.

In current RHOSP14, when cinder fails to create an cloned volume from the existing image cache volume, it retrieves image from glance but does never recreate it.

This causes a problem when using XtremIO as cinder backend, as XtremIO has a snapshot limit per volume group, which prevents that cloning when having a  number of volumes already created from the same image cache volume.

There is a bug report on launchpad[1], and the stable/rocky fix is already merged in master [2].

[1] https://bugs.launchpad.net/cinder/+bug/1801595
[2] https://review.opendev.org/#/c/663514/



How reproducible:
Always

Steps to Reproduce:
1. Configure XtremIO cinder backend and image cache enabled
2. Create 100(=xtremio_volumes_per_glance_cache) volumes from the same image
3. Again create some volumes from the same image

Actual results:
- Cinder always retrieves an image from glance

Expected results:
- Cinder creates a new image cache volume and create volumes using it.

Comment 9 errata-xmlrpc 2019-09-03 15:22:23 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2019:2618