Cinder Block Storage Service project overview and update. Highlights from the Train release, state of the project, and planning for the Ussuri development cycle.

1. Cinder
Project overview and update
Jay Bryant (Cinder PTL for Train)
Brian Rosmaita (Cinder PTL for Ussuri)
IRC: jungleboyj , rosmaita
Twitter: @jungleboyj , @br14nr
November 2019

2. What does Cinder do?
• Provide block storage service
• Implement services and
libraries to provide on demand,
self-service access to Block
Storage resources. Provide
Software Defined Block
Storage via abstraction and
automation on top of various
traditional backend block
storage devices.

3. Project background
• Founded during the Folsom
release of OpenStack
• 150 contributors in Stein (51
companies)
• 115 contributors in Train (39
companies)

4. Project background
Latest user survey adoption
numbers:
• Deployed in 98% of production
deployments
(out of 463 deployments)

5. Are we satisfied with 98%? NO!!!
● cinderlib
○ Reuse Cinder drivers in any Python code
■ No API, Scheduler, or Volume services
■ No Keystone, MySQL, or RabbitMQ
○ Used in:
○ “Cycle-trailing” release (since it depends on Cinder)
■ Stein: v0.9.0
■ Train: v1.0.0 on the way
→ Kubernetes: Ember-CSI
→ oVirt: Managed Block Storage
→ Ansible: Storage Role PoC

6. Mid-Cycle Meeting
● August 21-23 at Morrisville (North Carolina,
USA) Lenovo Site
● Approximately 5 people in Physical
Attendance
● Approximately 8 people remotely
participated
● Was a productive 3 days
Seriously, we do more than just eat at these meetings ----->

7. Agenda
● The State of Cinder
● Update on Train release
● Priorities for Ussuri

8. The State of Cinder

9. Contributions
● Slow decline of commits during the last few releases
● Why?
○ Transition from new feature development to bug fixing and
User Experience improvements
○ Drivers have stabilized and are more reliable
○ Deprioritization of upstream development by some
companies
● Is this good?
○ Yes ... and No
○ Cinder is a more mature and stable offering
○ The software doesn’t stabilize itself!

10. Participation in Train
Red Hat
22.9%
Dell EMC 14.2%
SUSE 9.5%
Others
21.5%
Lenovo 5.7%
NEC 7.1%
Huawei 5.1%

11. Drivers
● 59 supported drivers
○ All have third-party CI running in Python 3.7
○ Has remained stable for the last few releases with
about the same number going out as coming in
● 17 unsupported drivers
○ Some of these are unsupported due to their 3rd-party
CI systems not being able to handle Python 3.7
○ Will hopefully get this solved early in the Ussuri cycle

12. Bottom Line
● Cinder’s participation remains fairly healthy
● With cinderlib, the project has relevance in the
containerized world
○ This is particularly true for the backend drivers, so
hopefully vendors will beef up their support

13. Train Release Update

14. New Drivers
● New drivers in Train
○ Infortrend (restored; had been removed in Queens)
○ LINSTOR
○ RackScale Design NVMe-oF
○ Seagate -- FC and iSCSI
Additionally, many current drivers added enhanced
functionality. See the Train release notes for details.

15. Removed Drivers
● The following drivers, deprecated in Stein, failed to restore
their 3rd party CI during the Train cycle and were removed:
○ Nexenta Edge
○ Veritas HyperScale
○ Tintri
● The DRBDManage driver was removed; it is replaced by
the new LINSTOR driver

16. Unsupported Drivers
● Some due to lack of interest in keeping 3rd Party CI
running, and some due to unanticipated problems
converting 3rd Party CI to running under Python 3.7
○ See the “Unsupported Drivers” section of the
“Available Drivers” page in the Cinder documentation
○ https://docs.openstack.org/cinder/latest/drivers.html

17. Multi-Attach
● Several drivers added multi-attach support
○ HPE 3PAR and MSA
○ NEC
○ NexentaStor5 iSCSI and NFS
○ StorPool

18. Compression of volumes uploaded as images
● Admin-facing
○ uploaded qcow2 images are compressed using the native
qemu-img compression
○ Less data to upload/store, but requires more CPU
○ “On” by default (image_compress_on_upload option)

19. Compression of volumes uploaded as images
● User-facing
○ support added for hardware accelerated compression
○ User selects ‘compressed’ container format for the image
○ Has a software fallback if a HW accelerator is not configured
○ “Off” by default (allow_compression_on_image_upload
option)
○ See the Train release notes and “Accelerate image
compression” in the Cinder Administration Guide

20. No Untyped Volumes
● It’s now impossible to have untyped volumes
● There is a default volume type cleverly named __DEFAULT__
● It is assigned when:
○ A new volume is created without a type, and
○ The default_volume_type option is unset in cinder.conf

21. Upgrade Checks
● Allow administrators to check their environment to ensure
compatibility with the new Cinder release
● cinder-status upgrade check
● Upgrade-to-Stein checks were included in Cinder 14.0.1 (the
first Stein update release)
● Upgrade-to-Train checks are included in Cinder 15.0.0
There was a forum session about this yesterday -- if you missed it,
see the etherpad:
https://etherpad.openstack.org/p/shanghai-forum-upgrade-checker

22. Priorities for Ussuri

23. New features & enhancements
planned for Ussuri
● A reminder that this is just a statement of plan … actual
mileage may vary.
● Priorities will be discussed at the Ussuri PTG later this week.
○ https://etherpad.openstack.org/p/shanghai-ptg-cinder
● What follows is a short list of topics off the top of my head

24. Theme: Stability
● Want to increase automated test coverage to handle
scenarios not currently covered by unit, functional, or tempest
tests
○ Use the cinder-tempest-plugin to use the tempest
framework to do more thorough testing
○ Should be an easy integration for third party CI systems
to run these more thorough tests as well

25. OSSN-0085
● Applies to Ceph backend, but only when the rbd_keyring_conf
option is set
○ Option is unset by default
○ Vulnerability is: Ceph credentials can be leaked
○ Mitigation is: do not use the option
○ Option is deprecated in Ussuri for removal in “V”
○ Migration path: none
■ Contact me if you have a use case for this functionality
● https://wiki.openstack.org/wiki/OSSN/OSSN-0085

26. Driver Capabilities Reporting
● Not currently easy to see capabilities reported by drivers
enabled in an environment
● Working to make the information more readily available and
usable

27. More default volume types
● Having a single volume type default is too restrictive for
bigger clouds with multiple AZs and many tenants/projects
● There are use cases for per-project default volume types
○ There are some inelegant workarounds, we’d like to
enable a better user experience

28. Removal of V2 API
● V3 is a supserset of V2. Would like to remove duplicate V2
code
● Working with API consumers to determine possible impacts
● Did not happen in Train -- maybe in Ussuri?

29. Reference Links
● Release notes
○ https://docs.openstack.org/releasenotes/cinder/train.html
● Launchpad
○ https://launchpad.net/cinder
● Cinder wiki
○ https://wiki.openstack.org/wiki/Cinder
● Cinder YouTube
○ https://www.youtube.com/channel/UCJ8Koy4gsISMy0qW3CWZmaQ

30. Moar contributors!
● Everyone in this room can be a contributor
● “10 ways to contribute to an open source project without
writing code”
○ A 2013 article by Heiko W. Rupp, but still very relevant
○ http://tiny.cc/10-ways

31. @OpenSta
ck
THANKS.
Questions?
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