KIDSON

THE

BLOCK

NEW

THEpresented by mike perez

MIKEPEREZsenior developer for DreamHost

cinder core developer

WHAT

http://www.flickr.com/photos/neilhinchley/294337822/

• project exists since Folsom release, spun off Nova-volume

• cinder manages block storage• not object storage• not file level storage• volumes attach to VM Instances• boot from volume

• volumes have a lifecycle independent of VM instance

VOLUMETYPES

•Admin can create tiers of storage. e.g. two LVM backends, one with SSD’s and the other with HDD’s.

•Users can specify a tier they want when creating a volume.

ARCHITECTURALOVERVIEW

Cinder Client

Cinder API

Cinder Volume Cinder BackupCinder Scheduler

SQL DB

AMPQAMPQ

AMPQ

CINDERAPI•Volume create/delete/list/show•Create from image, snapshot

•Snapshot create/delete/list/show•Backups create/restore/list/delete/show•Volume attach/detach (called by Nova)•Volume types (more later)•Quotas

CINDERSCHEDULER•Chooses which back-end to place a new volume on

•Configurable plugins for schedulers

•Filter scheduler has plugins for filters and weights: chance, simple and filter.

•Filter scheduler Flow Example:

•Starts with list of all back-ends

•Filters according to capabilities

•Drivers report capabilities and state (e.g., free space)

•Default filters

•Volume types

•Sorts according to weights e.g., available free space

•Returns best candidate

CINDERVOLUME•Drivers: Called by Manager, contains back-end-specific code to communicate with various storage types (e.g., Linux LVM, storage controllers from various vendors, distributed file systems, etc.)•Admin can run multiple cinder-volume instances, each with its own configuration file describing settings and the storage back-end•As of Grizzly, one cinder-volume instance can manage multiple back-ends•Each back-end driver is generally configured to interact with one storage pool•Multi-threading

CINDERBACKUP

•A backup is an archived copy of a Volume stored in a object store.

•A backup is just the data that was written, unlike a snapshot which is the entire block.

HIGHLEVEL

Nova CinderVM Instance

Linux Volume Manager

KVM

ISCSI Initiator

LegendPersistent Volume DataPersistent Volume Control

/dev/hda

/dev/vda

ISCSI Initiator

ATTACHTHAT• Nova calls Cinder via its API, passing connection information.

e.g., host name, iSCSI initiator name, FC WWPNs

• Cinder API passes message to Cinder Volume.

• Manager does initial error checking and calls volume driver.

• Volume driver does any necessary preparation to allow the connection.e.g., give the nova host permissions to access the volume.

• Volume driver returns connection information, which is passed to Nova.e.g., iSCSI iqn and portal, FC WWPN.

• Nova creates the connection to the storage using the returned information.

• Nova passes the volume device/file to the hypervisor.

VOLUME

THEGRID

DRIVERREQUIREMENTS• Volume Create/Delete• Volume Attach/Detach• Snapshot Create/Delete• Create Volume from Snapshot• Get Volume Stats• Copy Image to Volume• Copy Volume to Image• Clone Volume

CURRENTDRIVERS

•Coraid (AoE)

•EMC VMAX/VNX (iSCSI)

•GlusterFS (GlusterFS)

•HP 3PAR (iSCSI/FC)

•HP LeftHand (iSCSI)

•Huawei T-series/Dorado (iSCSI)

•IBM Storwize family/SVC (iSCSI/FC)

•IBM XIV (iSCSI), LVM (iSCSI)

•NetApp (iSCSI/NFS)

•Nexenta (iSCSI)

•NFS (NFS)

•RBD (Ceph)

•Scality SOFS (scality)

•Sheepdog (sheepdog)

•Solaris (iSCSI)

•SolidFire (iSCSI)

•Windows Server 2012 (iSCSI)

•Zadara (iSCSI)

HAVANABOUNDGeneral Features

•Code cleanup and reorganization

•Attach volume to multiple hosts

•Read-only volumes

•Disk encryption

•FC SAN Zone / Access Control management

•Transfer volume ownership

•Volume Migration

•Work towards locality between instances and volumes

•State machine

•Volume rate limiting

New Drivers:

•IBM GPFS

•IBM zVM

•EMC Isilon (iSCSI)

•Local disk partitions

•Hitachi HUS (DF850) (iSCSI)

•Dell Equalogic

•Violin Memory v6000 (iSCSI)

THANKYOU!•Get started with Cinder:•https://wiki.openstack.org/wiki/Cinder

•Source Code:•http://github.com/openstack/cinder

•REST API Docs:•http://docs.openstack.org/api/openstack-block-storage/2.0

•Thanks Avishay Traeger from IBM for letting me copy things out of his slides.

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email: thingee@gmail.com