Bug 1033180

Summary: [RFE][cinder]: Attach a single volume to multiple hosts
Product: Red Hat OpenStack Reporter: Stephen Gordon <sgordon>
Component: openstack-cinderAssignee: Eric Harney <eharney>
Status: CLOSED ERRATA QA Contact: Tzach Shefi <tshefi>
Severity: medium Docs Contact:
Priority: high    
Version: 14.0 (Rocky)CC: achernet, akarlsso, amedeo.salvati, brault, cschwede, ebarrera, eharney, gcharot, gfidente, gideon.agmon, jamsmith, jniu, jschluet, knoha, lmarsh, markmc, mlehmann, mlinden, myllynen, mzheng, nchandek, nlevinki, nobody+akarlsso, pgrist, pmorey, racedoro, roxenham, sclewis, scohen, srevivo, tshefi, tvvcox, yaron.aboodaga, yohmura, yrabl
Target Milestone: Upstream M2Keywords: FutureFeature, TechPreview, Triaged
Target Release: 14.0 (Rocky)Flags: tshefi: automate_bug+
Hardware: Unspecified   
OS: Unspecified   
URL: https://blueprints.launchpad.net/cinder/+spec/multi-attach-volume
Whiteboard:
Fixed In Version: openstack-cinder-13.0.0-0.20180710093321.64bebcd.el7ost Doc Type: Technology Preview
Doc Text:
This release adds a Technology Preview of the ability to attach a volume to multiple hosts or servers simultaneously in both cinder and nova with read/write (RW) mode when this feature is supported by the back end driver. This feature addresses the clustered application workloads use case that typically requires active/active or active/standby scenarios.
 Story Points: ---
Clone Of:
: 1624971 1661022 (view as bug list) Environment:
Last Closed: 2019-01-11 11:47:00 UTC Type: Feature Request
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1033185, 1623365, 1625971    
Bug Blocks: 1281573, 1022045, 1213674, 1230807, 1339072, 1442136, 1476900, 1478186, 1496484, 1613486, 1624971, 1661022, 1694113, 1746984, 1761502, 1790753    

Description Stephen Gordon 2013-11-21 16:18:40 UTC 
Cloned from launchpad blueprint https://blueprints.launchpad.net/cinder/+spec/multi-attach-volume.

Description:

Currently, the existing block storage (cinder) drivers allow for only a single volume to be attached to a single VM instance via iSCSI or Fibre Channel. To support a cluster, a single volume would need to be exported to multiple host. In this case vCenter will be used as an example, but any Hypervisor that supports clusters could require this functionality.

The Cinder etherpad https://etherpad.openstack.org/summit-havana-cinder-multi-attach-and-ro-volumes was present at the Havana Design summit resulted in the majority of the work to be completed in nova project. This work includes the looping mechanism that's responsible for calling the cinder drivers for each host in the cluster.

The Cinder work is not yet determined but would require minor work in tracking that a volume has multiple host attached to it.  Possibly changing the database entries for what volume is attached to a single host to a list of host. More work may be required once test have been ran to verify the data flow between multiple attach points.

This blueprint in for the limited cinder work that would be required from the following Nova blueprint: https://blueprints.launchpad.net/nova/+spec/fc-support-for-vcenter-driver

Specification URL (additional information):

None
Comment 1 Stephen Gordon 2013-11-27 20:35:49 UTC 
*** Bug 1033178 has been marked as a duplicate of this bug. ***
Comment 4 Yogev Rabl 2015-05-06 14:45:16 UTC 
Feature specs:
https://review.openstack.org/#/c/154135/8/specs/kilo/multi-attach-volume.rst
Comment 8 Mike McCune 2016-03-28 22:33:16 UTC 
This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions
Comment 12 Elise Gafford 2016-08-22 18:54:45 UTC 
cinderclient 1.3.0 python-cinderclient-1.8.1-0.20160607191316.c955397.el7ost (which is in OSP10) is necessary but insufficient to address this bug. Per discussion, adding needinfo on eharney to clarify details of remaining work. Moving to RHOS 11, as this remaining work is by his estimation very unlikely to occur in 10.
Comment 15 Eric Harney 2016-09-14 14:27:27 UTC 
Current multi-attach blueprint for Nova:
https://blueprints.launchpad.net/nova/+spec/multi-attach-volume

Nova Spec: https://review.openstack.org/#/c/304681/
Comment 16 Stephen Gordon 2016-09-15 07:25:10 UTC 
(In reply to Eric Harney from comment #15)
> Current multi-attach blueprint for Nova:
> https://blueprints.launchpad.net/nova/+spec/multi-attach-volume
> 
> Nova Spec: https://review.openstack.org/#/c/304681/

I believe the downstream tracker for these is https://bugzilla.redhat.com/show_bug.cgi?id=1033185
Comment 18 Stephen Gordon 2016-12-23 15:33:54 UTC 
*** Bug 1230807 has been marked as a duplicate of this bug. ***
Comment 30 Eric Harney 2018-05-10 14:46:25 UTC 
Upstream specs:

https://blueprints.launchpad.net/nova/+spec/multi-attach-volume

https://blueprints.launchpad.net/cinder/+spec/multi-attach-v3-attach
Comment 33 Tzach Shefi 2018-08-29 11:35:28 UTC 
Benny hit Nova issues bz1623365 while testing automation for this RFE.
Comment 38 Avi Avraham 2018-11-21 13:59:32 UTC 
Verified according to test plan 
RPM package version :
python-cinder-13.0.1-0.20181013185427.31ff628.el7ost.noarch
python2-cinderclient-4.0.1-0.20180809133302.460229c.el7ost.noarch
puppet-cinder-13.3.1-0.20181013114719.25b1ba3.el7ost.noarch
openstack-cinder-13.0.1-0.20181013185427.31ff628.el7ost.noarch
Comment 42 errata-xmlrpc 2019-01-11 11:47:00 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2019:0045
Comment 43 James Smith 2019-01-18 21:10:32 UTC 
This enhancement lets you attach a Block Storage volume to multiple hosts. 
You can attach a volume to multiple hosts or servers simultaneously in both the Block Storage (cinder) and Compute (nova) services with read/write (RW) mode. The feature addresses the clustered application workloads use case, which typically requires active/active or active/standby scenarios. The feature is intended for use with basic volume operations. Known limitations include encrypted volumes and migration.
Availability depends on back end support.