Difference between revisions of "Cinder"

Jump to: navigation, search

Revision as of 01:51, 18 December 2014

Official Title: OpenStack Block Storage Cinder

PTL: Mike Perez <thingee at gmail d0t com>

Mission Statement:

To 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.

[Cinder on launchpad (including bug tracker and blueprints)]

[Source code]

[Developer docs]

1 Description
2 Project Meetings
3 Getting in Touch
4 Related projects
5 Core Volume Drivers
6 Cinder Plugins
7 Configuring devstack to use your driver and backend
8 Cinder Brick Proposal

Description

Cinder is a Block Storage service for OpenStack. It's designed to allow the use of either a reference implementation (LVM) to present storage resources to end users that can be consumed by the OpenStack Compute Project (Nova). The short description of Cinder is that it virtualizes pools of block storage devices and provides end users with a self service API to request and consume those resources without requiring any knowledge of where their storage is actually deployed or on what type of device.

Project Meetings

See Meetings/Cinder.

Getting in Touch

We use the openstack-dev@lists.openstack.org mailing list for discussions and we all hang out in #openstack-cinder on freenode.

Related projects

Python Cinder client

Core Volume Drivers

For a list of the core drivers in each OpenStack release and the volume operations they support, see https://wiki.openstack.org/wiki/CinderSupportMatrix

Cinder Plugins

How to submit a plugin/driver: https://wiki.openstack.org/wiki/Cinder/how-to-contribute-a-driver

Cinder Plugin/Driver certification page: https://wiki.openstack.org/wiki/Cinder/certified-drivers

The following plugins (from other sources) are available for this project

Mellanox Cinder Plugin Mellanox Cinder Plugin

Configuring devstack to use your driver and backend

One of the things you'll be required to do when submitting a new driver is running your backend and driver in a devstack environment and executing the tempest volume tests against it. Currently we provide a driver_cert wrapper (mentioned in the how-to-contribute-a-driver section). One thing that causes some confusion is how do I configure devstack to use my backend device. It used to be that your driver info would have to be added to lib/cinder in devstack to set your options. We then created a cinder/plugin module in devstack. Fortunately though it's MUCH easier than that. For *most* drivers, the only changes that are made consist of cinder.conf file changes. That can easily be accomplished by using devstacks local.conf file (more info here: http://devstack.org/configuration.html). For more complex actions (like the need to install packages etc, the plugin directory in devstack can be used). An example of what this file would look like to add driver FOO is shown below, the default localrc section is included for completeness, but the section of interest is the post-config cinder.conf section:

[[local|localrc]]
_{:# Passwords

ADMIN_PASSWORD=password

MYSQL_PASSWORD=password

RABBIT_PASSWORD=password

SERVICE_PASSWORD=password

SERVICE_TOKEN=password

SCREEN_LOGDIR=/opt/stack/logs

HOST_IP=172.16.140.246

disable_service n-net

enable_service q-svc

enable_service q-agt

enable_service q-dhcp

enable_service q-l3

enable_service q-meta

enable_service neutron}

# These options define expected driver capabilities
TEMPEST_VOLUME_DRIVER=foo
TEMPEST_VOLUME_VENDOR="Foo Inc"
TEMPEST_STORAGE_PROTOCOL=iSCSI

# These options allow you to specify a branch other than "master" be used
CINDER_REPO=https://review.openstack.org/openstack/cinder
CINDER_BRANCH=refs/changes/83/72183/4

# Disable security groups entirely
Q_USE_SECGROUP=False
LIBVIRT_FIREWALL_DRIVER=nova.virt.firewall.NoopFirewallDriver
CINDER_SECURE_DELETE=False

[[post-config|$CINDER_CONF]]
volume_driver = cinder.volume.drivers.foo.FooDriver
foos_var = something
another_foo_var = something-else

Cinder Brick Proposal

https://wiki.openstack.org/wiki/CinderBrick

Retrieved from "https://wiki.openstack.org/w/index.php?title=Cinder&oldid=70704"

@@ Line 1: / Line 1: @@
+'''Official Title:''' OpenStack Block Storage Cinder<br />
+'''PTL:''' Mike Perez <thingee at gmail d0t com><br />
-= OpenStack Block Storage ("Cinder") =
+'''Mission Statement:''' <blockquote>To 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.</blockquote>
 {| border="1" cellpadding="2" cellspacing="0"
@@ Line 11: / Line 13: @@
 |}
-== Mission Statement ==
+=== Description ===
-To 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.
-== Description ==
 Cinder is a Block Storage service for OpenStack.  It's designed to allow the use of either a reference implementation (LVM) to present storage resources to end users that can be consumed by the OpenStack Compute Project (Nova).  The short description of Cinder is that it virtualizes pools of block storage devices and provides end users with a self service API to request and consume those resources without requiring any knowledge of where their storage is actually deployed or on what type of device.
-== Related projects ==
+=== Project Meetings ===
-* Python Cinder client
+See [[CinderMeetings|Meetings/Cinder]].
-* Block Storage API documentation
-== What is Cinder ? ==
-Cinder provides an infrastructure for managing volumes in OpenStack.  It was originally a Nova component called nova-volume, but has become an independent project since the Folsom release.
-== Reasoning: ==
-# Nova is currently a very large project; managing all of the dependencies in linkages of services within Nova can make the  ability to advance new features and functionality very difficult.
-# As a result of the many components and dependencies in Nova, it's difficult for anybody to really have a complete view of Nova and to be a true expert.  This makes the job of core team member on Nova very difficult, and inhibits good thorough reviews of bug and blueprint submissions.
-# Block storage is a critical component of [[OpenStack]], as such it warrants focused and dedicated attention.
-# Having Block Storage as a dedicated core project in [[OpenStack]] enables the ability to greatly improve functionality and reliability of the block storage component of [[OpenStack]]
-== Documents: ==
-* Cinder deep dive (updated for Grizzly): [[File:cinder-grizzly-deep-dive-pub.pdf]]
-== Minimum Driver Features ==
-See [https://github.com/openstack/cinder/blob/master/doc/source/devref/drivers.rst driver dev docs]
-=== Keeping consistant with multi backend ===
-In order to maintain consistency with multi backend, do not directly use FLAGS.my_flag, instead use the self.configuration that is provided to the volume drivers. If this does not exist, look @ lvm.py and add it to your driver. using FLAGS.my_flag instead of self.configuration.my_flag will cause multi backend to not work properly. Multi backend relies on the configurations to be within a specific config group in the config file, and the self.configuration abstracts that away from the drivers.
-== Keeping informed and providing '''CONSTRUCTIVE INPUT''' ==
-The Cinder team currently meets on a weekly basis in #openstack-meeting at 16:00 UTC on Wednesdays.  I try to keep the meetings wiki agenda page http://wiki.openstack.org/CinderMeetings up to date and follow it.  Also keep in mind that '''anybody''' is able to add/suggest agenda items via the meeting wiki page.
-Of course, there's also IRC... a number of us monitor #openstack-cinder or you can always send a PM to jgriffith (that's me)
-== Concerns from the community: ==
-=== Compatibility and Migration: ===
-There has been a significant amount of concern raised regarding "compatibility"; unfortunately this seems to mean different things to different people.  For those that haven't looked at the Cinder code or tried a demo in devstack, here are some question/answers:
-* Do the same nova client commands I use for volumes today still work the same? '''YES'''
+=== Getting in Touch ===
-* Do the same euca2ools that I use for volumes today still work the same? '''YES'''
+We use the [http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev openstack-dev@lists.openstack.org] mailing list for discussions and we all hang out in #openstack-cinder on freenode.
-* Does block storage still work the same as it does today in terms of LVM, iSCSI and the drivers that are curently in place? '''YES'''
-* Are the associated database tables the same as they are in the current nova volume code?  '''For the most part YES, all volume related tables and columns are migrated, non-volume related tables however are not present'''
-* Does it use the same nova database as we use today? '''No, it does require a new independent database'''
-* Are you going to implement cinder with complete disregard for my current install and completely change everything out from under me?  '''ABSOLUTELY NOT'''
-* Are you going to test migrating from nova-vol to Cinder? '''YES'''
-* Are those migration tests going to be done just using fakes/unit tests?  '''NO, we would require running setups, most likely devstack'''
-* Are you planning to provide migration scripts/tools to move from nova to cinder?  '''YES'''
-=== Additional thoughts to keep in mind: ===
+=== Related projects ===
-* The Cinder core team is fortunate enough to have a number of members who currently work for companies that are using [[OpenStack]] in production environments.  There is a strong representation and the concerns of Providers is in fact a major consideration
+* [https://github.com/openstack/python-cinderclient Python Cinder client]
-* The goal is '''NOT''' to throw away nova-volume as it is today, but to separate it, focus on it and improve it.
-* Migration is one of the top priorities for introduction of Cinder into Folsom (regardless of whether nova-volume is still in place or not).  This is something that is just considered a part of the requirements for the project.
-== Cinder Core Drivers ==
+=== Core Volume Drivers ===
 For a list of the core drivers in each OpenStack release and the volume operations they support, see https://wiki.openstack.org/wiki/CinderSupportMatrix
-== Notes About Submitting Patches ==
+=== Cinder Plugins ===
-Everyone is welcome to sign the CLA and submit code.  Please be sure you familiarize yourself with the "how to contribute guide" (https://wiki.openstack.org/wiki/How_To_Contribute#If_you.27re_a_developer).
-Keep in mind, there is a disproportionate number of submitters to reviewers.  YOU can help with this!!  Anybody is welcome to review patches, jump in, give a review.  It's a great way to learn more about the code and to help you make better submissions in the future.  It also helps your karma, when you submit a patch if you're an active reviewer core team members are more likely to notice your patch and give it some attention before some others.
-== Cinder Plugins ==
 How to submit a plugin/driver: https://wiki.openstack.org/wiki/Cinder/how-to-contribute-a-driver
@@ Line 80: / Line 36: @@
 * [https://wiki.openstack.org/wiki/Mellanox-Cinder Mellanox Cinder Plugin] Mellanox Cinder Plugin
-== Configuring devstack to use your driver and backend ==
+=== Configuring devstack to use your driver and backend ===
 One of the things you'll be required to do when submitting a new driver is running your backend and driver in a devstack environment and executing the tempest volume tests against it.  Currently we provide a driver_cert wrapper (mentioned in the how-to-contribute-a-driver section).  One thing that causes some confusion is how do I configure devstack to use my backend device.  It used to be that your driver info would have to be added to lib/cinder in devstack to set your options.  We then created a cinder/plugin module in devstack.  Fortunately though it's MUCH easier than that.  For *most* drivers, the only changes that are made consist of cinder.conf file changes.  That can easily be accomplished by using devstacks local.conf file (more info here: http://devstack.org/configuration.html).  For more complex actions (like the need to install packages etc, the plugin directory in devstack can be used).  An example of what this file would look like to add driver FOO is shown below, the default localrc section is included for completeness, but the section of interest is the post-config cinder.conf section:
@@ Line 121: / Line 77: @@
 <br />
-== Cinder Brick Proposal ==
+=== Cinder Brick Proposal ===
 https://wiki.openstack.org/wiki/CinderBrick