These slides were presented at the Boston Summit for people interested in learning how to start contributing to OpenStack's Block Storage project, Cinder. Includes an overview of Cinder's architecture, an introduction to our development processes and a description of our code tree.

1. 1

2. Cinder On-Boarding Education
Sean McGinnis (Huawei), Jay Bryant (Lenovo)
May 9, 2017 Boston

3. 3
● Cinder’s Repos
● Brief overview of Cinder architecture/organization
● Cinder’s team
● Pointers to Upstream Institute education
● Applying OpenStack Process
● Cinder’s code
● Testing changes to Cinder
Agenda

4. 4
Cinder Repos
● Brick Cinderclient for Standalone Cinder
○ https://github.com/openstack/python-brick-cinderclient-ext
● Cinderclient:
○ https://github.com/openstack/python-cinderclient
● Main Cinder repository:
○ https://github.com/openstack/cinder
● os-brick shared library:
○ https://github.com/openstack/os-brick

5. 5
● Provides persistent
block storage resources
for an OpenStack
cloud.
● Supports multiple
back-ends. Nearly 100
volume drivers in tree.
Cinder Overview

6. 6
Vendor Backends
● Drivers from many different vendors
● Different protocols used depending on the driver
○ iSCSI
○ Fibre Channel
○ RBD
○ Etc.

7. 7
●Block Device Driver (local)
●Blockbridge (iSCSI)
●Coho (NFS)
●CoprHD (FC, iSCSI, scaleio)
●Datera (iSCSI)
●Dell/EMC PS Series (iSCSI)
●Dell/EMC ScaleIO (scaleio)
●Dell/EMC UnityDriver (FC, iSCSI)
●Dell/EMC VMAX (FC, iSCSI)
●Dell/EMC VNX (iSCSI/FC)
●Dell/EMC XtremIO (iSCSI/FC)
●Disco (disco)
●DRBD (DRBD/iSCSI)
●FalconStor (iSCSI/FC)
●Fujitsu ETERNUS (iSCSI/FC)
●GlusterFS (GlusterFS)
●HGST (NFS)
●HPE 3PAR (iSCSI/FC)
●HPE LeftHand (iSCSI)
●HPE MSA (iSCSI/FC)
●Huawei (iSCSI/FC)
●Huawei FusionStorage DSWare (iSCSI)
●IBM Flashsystem (iSCSI/FC)
●IBM GPFS (GPFS/NFS)
●IBM Storage (iSCSI/FC)
●IBM Storwize SVC (iSCSI/FC)
●Infinidat Infinibox (FC)
●Infortrend (iSCSI/FC)
●Kaminario (iSCSI)
●Lenovo (iSCSI/FC)
●LVM (iSCSI) – Reference*
●NEC M-Series (FC/iSCSI)
●NetApp 7-Mode (iSCSI/FC/NFS)
●NetApp C-Mode (iSCSI/FC/NFS)
●NetApp ONTAP (iSCSI/NFS/FC)
●Nexenta (iSCSI/NFS)
●Nexenta Edge (iSCSI/NBD)
●NFS – Reference
●Nimble Storage (iSCSI/FC)
●ProphetStor (iSCSI/FC)
●Pure Storage (iSCSI/FC)
●Quobyte (quobyte)
●RBD (Ceph) - Reference
●Reduxio (iSCSI)
●Scality SOFS (scality)
●Sheepdog (sheepdog)
●SolidFire (iSCSI)
●Synology (iSCSI)
●Tegile (iSCSI/FC)
●Tintri (NFS)
●Veritas HyperScale
●Virtuozzo Storage (NFS)
●VMWare (VMDK)
●Windows (SMB)
●X-IO (iSCSI/FC)
●Zadara (iSCSI)
●ZFS (iSCSI/NFS)
●ZTE (iSCSI)
Backends Drivers
Note: Supported drivers list. Full list may be seen here: https://docs.openstack.org/developer/cinder/drivers.html

8. 8
Volume Attachment
LVM
Nova
VM instance
/dev/vda
KVM
iSCSI
initiator
Cinder
iSCSI
target
Note that iSCSI is just
an example – several
additional protocols
are supported
(e.g., FC, NFS)
Legend
Persistent volume control
Persistent volume data

9. 9
Cinder’s Team
● PTL
○ Sean McGinnis (smcginnis)
● Core Team
○ Walt Boring (hemna)
○ Jay Bryant (jungleboyj)
○ Scott D’Angelo (scottda)
○ Michal Dulko (dulek)
○ Patrick East (patrickeast)
○ Gorka Eguileor (geguileo)
○ John Griffith (jgriffith)
○ Eric Harney (eharney)
○ Ivan Kolodyazhny (e0ne)
○ Mike Perez (thingee)
○ Duncan Thomas (DuncanT)
○ Xing Yang (Xyang)
○ Huang Zhiteng (winston-d)

10. 10
Upstream Institute
● https://docs.openstack.org/upstream-training/
● Day and a half education session to help people new to
OpenStack
● Lead by OpenStack Foundation members and
volunteers
● Miss the Boston session … No problem, join us in
Sydney!

11. 11
Upstream Institute - Key Info
● VM image to get your development started
● OpenStack account setup
○ https://docs.openstack.org/upstream-training/workflow-reg-and-accou
nts.html
● Launchpad/Storyboard introduction
○ https://docs.openstack.org/upstream-training/workflow-task-tracking.h
tml
● Workflow introduction
○ https://docs.openstack.org/upstream-training/workflow-training-contrib
ution-process.html
● Introduction to gerrit and code reviews
○ https://docs.openstack.org/upstream-training/workflow-gerrit.html
○ https://docs.openstack.org/upstream-training/workflow-reviewing.html

12. 12
Cinder in OpenStack’s Processes

13. 13
Cinder Bugs and Blueprints
● Still currently using Launchpad
● https://launchpad.net/cinder

14. 14
Bug Tags
● low-hanging-fruit
● doc
● i18n
● security
● ops
● <SERIES>-rc-potential
● <SERIES>-backport-potential
● driver/drivers
● gate-failure
● ceph
● cinder
● backup-service
● create-volume-from-snapshot

15. 15
Cinder Specs
● https://github.com/openstack/cinder-specs
● We request specs for more complicated changes
● Organized by release (specs/<release>)
● Template from which to start: specs/template.rst
● Before pushing your spec run ‘tox -e docs,py27,pep8’
○ Look for any errors and please correct before pushing
for review

16. 16
IRC and Cinder Meetings
● #openstack-cinder
○ Please join us for all things Cinder
○ Try @? for some (╯°□°)╯︵ ┻━┻ fun
● Weekly Meeting
○ Wednesdays at 16:00 UTC
○ #openstack-meeting
○ https://wiki.openstack.org/wiki/CinderMeetings
○ Add agenda items with your IRC nickname to the wiki
page above

17. 17
Typical Development Cycle
● Pike release schedule
○ https://releases.openstack.org/pike/schedule.html
● Milestone 2
○ Spec freeze
○ New driver merge deadline
● Milestone 3
○ New feature freeze
○ Move focus to testing and bug fixes
○ Need 3rd party CI’s functional to avoid addition of unsupported flag
● RC
○ Bug fixes only
● Some flexibility around dates allowed with core team and PTL’s discretion

18. 18
3rd Party CI
● 3rd Party CI is required for all Cinder drivers
○ https://wiki.openstack.org/wiki/Cinder/tested-3rdParty-drivers
● Purpose
○ To ensure that a vendor’s driver functions properly as changes merge to
the Cinder tree
○ To show that patches against a vendor’s driver work
● Policy
○ 3rd Party CI must run successfully against a weekly job executed to test
that CI’s are reporting
○ 3rd Party CI must fail a job submitted that should fail all 3rd Party CI
testing.
○ A vendor CI that doesn’t meet these requirements during a release
cycle is marked ‘Unsupported’ and consumers have to update their
configs to indicate they wish to run an unsupported driver
○ Continued non-compliance results in driver removal in the next release.

19. 19
3rd Party CI - Review Implications
● If a patch fails all CI’s, something is
wrong
● Patches against a driver must pass
the vendor’s CI before being
merged

20. 20
About Reviews
● We need your help!
● Good way to get involved with Cinder
○ Learn the code and the project organization
○ Don’t need to know how Cinder works to catch logic errors and typos
● Gets you visibility to the Cinder team
● Review inboxes:
○ Cinder review inbox
○ os-brick review inbox
○ python-brick-cinderclient-ex review inbox
● Track how we are doing:
○ http://cinderstats-dellstorage.rhcloud.com/

21. 21
Cinder Code Layout - Top Level
● api-ref -- Source documentation for v1,2 and 3 Cinder API
● cinder -- Cinder’s source directory with high level implementations at the top
level (i.e. exceptions, i18n, policy, utils, etc.)
● doc -- Developer documentation that is published to the OpenStack website
● etc -- Config files that are not automatically generated
● rally-jobs -- Rally tasks and plugins to be run by OpenStack CI
● releasenotes -- Contains release notes for patches
● tools -- Config generation script, driver list generation, etc.

22. 22
Cinder Code Layout - /cinder
● api -- v1, 2, 3 and API extension implementation
● backup -- Backup driver API and implementations
● brick -- Legacy brick directory, mostly migrated to os-brick library
● cmd -- Starter scripts for Cinder’s processes (api, scheduler, volume, etc.)
● common -- Shared files for config, sqlalchemy, etc.
● compute -- Source for interfacing with Nova
● config -- Source files for config file generator
● consistencygroup -- Consistency Group API implementation
● db -- sqlalchemy migration scripts and DB API implementation

23. 23
Cinder Code Layout - /cinder (cont.)
● group -- Generic Group API implementation
● hacking -- Hacking check implementation
● image -- Source for interfacing with Glance
● interface -- Base interface definition for driver validation and reference
● keymgr -- Simple security key implementation
● locale -- Translation files for log messages
● message -- User message API implementation
● objects -- Implementation of Cinder’s Oslo Versioned Objects
● scheduler -- Scheduling option implementations
● tests -- Compliance, functional, tempest and unit test implementation
● transfer -- API implementation of volume transfer
● volume -- Implementation of API and drivers for volumes
● wsgi -- Cinder Web Server Gateway Interface implementation
● zonemanager -- Fibre Channel Zonemanager implementation

24. 24
Release Notes
● Developer’s way to communicate to the end user
● Most important for changes that impact Cinder’s functionality
● Documents:
○ Security issue fixes,
○ New features
○ Upgrade notes
○ Known issues
○ Deprecation notes
● Not required for every change, but important for anything that directly
impacts packagers or users

25. 25
Tox Tests
● Tox is a test runner used by most OpenStack projects
● Many of the same test targets, but a few specific to Cinder
● Before submitting a patch, best to at least run py27 and pep8 targets
(tox -e py27,fast8)
py27, py35 Runs unit tests using either Python 2.7 or 3.5
genopts Must be run when adding any new config options to regenerate opts.py file
used to create the sample config
pep8, fast8 Runs code checks to make sure it conforms to coding style and hacking
checks to look for specific conditions
releasenotes Validates new release notes (must commit first!)
compliance Useful for driver developers, will validate all required driver interfaces are
implemented

26. Q & A