RHBA-2018:2136 - Bug Fix Advisory

Topic

Updated OpenStack Block Storage packages that resolve various issues are
now available for Red Hat OpenStack Platform 9.0 (Mitaka) for RHEL 7.

Description

Red Hat OpenStack Platform provides the facilities for building a private
or public infrastructure-as-a-service (IaaS) cloud running on commonly
available physical hardware. This advisory includes packages for:

• OpenStack Block Storage service

OpenStack Block Storage (cinder) manages block storage mounting and the
presentation of such mounted block storage to instances. The back-end
physical storage can consist of local disks, Fiber Channel, iSCSI, and/or
NFS mounts attached to Compute nodes. In addition, Block Storage supports
volume backups, and snapshots for temporary save and restore operations.
Programmatic management is available through the Block Storage service's
API.

Changes to the openstack-cinder component:

• Race conditions on the volume service when reporting stats from the storage backend means that the scheduler uses out-of-date stats. This allows them to create more volumes than they should. Remove these race conditions. Schedulers use more up-to-date stats, which bring the number of volumes allowed to be created closer to the configured limits. (BZ#1553737)
• Previously, certain method calls for backup/restore operations blocked the eventlet's thread switching. Consequently, operations were slower and connection errors were observed in the database and RabbitMQ logs. With this update, proxy blocking method calls were changed into native threads to prevent blocking. As a result, restore and backup operations are faster and the connection issues are resolved. (BZ#1464146)
• Cinder uses a synchronization lock to prevent duplicate entries in the volume image cache. The scope of the lock was too broad, and caused simultaneous requests to create a volume from an image to compete for the lock, even when the image cache was not enabled. Simultaneous requests to create a volume from an image would be serialized, and not run in parallel.

The synchronization lock has been updated to minimize the scope of the lock, and to take effect only when the volume image cache is enabled. Simultaneous requests to create a volume from an image run in parallel when the volume image cache is disabled. When the volume image cache is enabled, locking is minimized to ensure only a single entry is created in the cache. (BZ#1575720)

Solution

Before applying this update, ensure all previously released errata relevant
to your system have been applied.

Red Hat OpenStack Platform 9 runs on Red Hat Enterprise Linux 7.4.

The Red Hat OpenStack Platform 9 Release Notes contain the following:

• An explanation of the way in which the provided components interact to

form a working cloud computing environment.

• Technology Previews, Recommended Practices, and Known Issues.
• The channels required for Red Hat OpenStack Platform 9, including which

channels need to be enabled and disabled.

The Release Notes are available at:
https://access.redhat.com/documentation/en/red-hat-openstack-platform/9/paged/release-notes

This update is available through 'yum update' on systems registered through
Red Hat Subscription Manager. For more information about Red Hat
Subscription Manager, see:

https://access.redhat.com/documentation/en-US/Red_Hat_Subscription_Management/1/html/RHSM/index.html

Affected Products

• Red Hat OpenStack 9 x86_64

Fixes

• BZ - 1464146 - Problem in creating several cinder backups at same time
• BZ - 1553737 - Delay in stats reporting in cinder
• BZ - 1567180 - Fix Lun ID 0 in HPE 3PAR driver
• BZ - 1575720 - Cinder's image volume cache sync lock prevents parallel image downloading

CVEs

(none)

References

(none)