Bug 1033185

Summary:	[RFE][nova]: a shared volume can be accessed by many instances
Product:	Red Hat OpenStack	Reporter:	Stephen Gordon <sgordon>
Component:	openstack-nova	Assignee:	Matthew Booth <mbooth>
Status:	CLOSED ERRATA	QA Contact:	Archit Modi <amodi>
Severity:	high	Docs Contact:
Priority:	urgent
Version:	unspecified	CC:	abehl, achernet, akarlsso, amodi, arkady_kanevsky, brault, ebarrera, eglynn, eharney, gideon.agmon, jhakimra, jjoyce, jniu, kchamart, knoha, lyarwood, markmc, mbooth, nlevinki, pmorey, rajini.karthik, sclewis, sgordon, srevivo, tvvcox, weiyongjun, yaron.aboodaga, yohmura
Target Milestone:	Upstream M2	Keywords:	FutureFeature, Triaged
Target Release:	14.0 (Rocky)
Hardware:	Unspecified
OS:	Unspecified
URL:	https://blueprints.launchpad.net/nova/+spec/multi-attach-volume
Whiteboard:	upstream_milestone_none upstream_definition_pending-approval upstream_status_slow-progress
Fixed In Version:	openstack-nova-18.0.0-0.20180710150340.8469fa7	Doc Type:	Enhancement
Doc Text:		Story Points:	---
Clone Of:	1033178
Clones:	1552736 (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:
Bug Blocks:	1281573, 1022045, 1033180, 1339072, 1442136, 1476900, 1478186, 1496484, 1521118, 1552736, 1613486, 1624971, 1661022, 1694113, 1732850, 1746984, 1761502

Description Stephen Gordon 2013-11-21 16:26:52 UTC

Cloning to Nova as there are impacts here too. No Nova-specific blueprint exists (to my knowledge) covering these impacts at this time.

+++ This bug was initially created as a clone of Bug #1033178 +++

Cloned from launchpad blueprint https://blueprints.launchpad.net/cinder/+spec/shared-volume.

Description:

Provide the ability to attach a single volume to multiple instances simultaneously.  In order to do this R/W there are a number of issues involved with respect to data corruption etc.  As a first pass it would be very useful to introduce a Read Only option that could be specified during attach and used to allow simultaneous attach to multiple instances.

Most of this will require work in Nova/Compute but there will need to be some comprehension added to Cinder, and perhaps the ability to mark a volume as Read Only might be useful as well.

This R/O volumes could be especially useful for things like Images and even D2D backups.  

There's also a need for FC environments to multi-attach in general.

Specification URL (additional information):

None

Comment 2 Stephen Gordon 2013-11-27 20:39:17 UTC

I'm actually currently working this against https://blueprints.launchpad.net/cinder/+spec/multi-attach-volume but both it and the blueprint in the description overlap.

Comment 3 Dave Allan 2013-12-12 03:16:34 UTC

Note that one of the use cases here is clusters with SCSI3 persistent reservation based fencing, which expands the scope quite a bit to include virtio-scsi and NPIV.  Libvirt is most of the way through the implementation of expanded support for NPIV which might help here.

Comment 6 Mike McCune 2016-03-28 23:11:51 UTC

This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions

Comment 8 Stephen Gordon 2016-07-07 16:15:26 UTC

Missed Newton approvals, moving to Ocata.

Comment 11 Stephen Gordon 2016-10-28 18:15:31 UTC

Moving to Lee initially based on a discussion we had today. This feature and issues related to it, among others, led to discussion of a significant update/rewrite of the way Cinder and Nova work together to attach volumes at the Barcelona OpenStack summit:

    https://etherpad.openstack.org/p/ocata-nova-summit-cinder-session

The long and the short of it is there is quite a lot of work to do here, I would like to keep this on our RHOSP 11/Ocata work list to ensure forward progress but am not confident of 100% completion of the end to end feature in that time frame.

Comment 25 Stephen Gordon 2017-07-25 14:27:41 UTC

Hi Matt,

How has this been tracking upstream through Pike? How much of it remains outstanding?

Thanks,

Steve

Comment 37 Matthew Booth 2018-06-05 16:39:33 UTC

Upstream cinder has support for multiattach on the following backend drivers:

scaleio
infinidat
lvm
solidfire
zfssaiscsi

A couple of things to note:

storwize_svc appears to publish the multiattach capability if the storwize_svc_multihostmap_enabled config option is set to True, but it's marked deprecated and the help text says it has no effect.

There's a cinder config option for netapp called netapp_enable_multiattach which seems to relate to an internal netapp multiattach feature, and does not enable cinder multiattach.

It would be good to get independent confirmation of the above, as I have created the above primary from grep.

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