[Doc] Share Migration Ocata Improvements

[OpenStack Infra]

https://review.openstack.org/406305
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commit 53539c0e1d9f6d7abaef2fb31dad84e86d674372
Author: Rodrigo Barbieri <email address hidden>
Date: Thu Nov 24 15:52:03 2016 -0200

    Share Migration Ocata Improvements

    Implemented several improvements to share migration
    according to spec [1].

    Summary of changes:
    - Snapshot restriction in API has been changed to return error only
    when parameter force-host-assisted-migration is True
    - Added preserve_snapshot to API and migration_check_compatibility
    driver interface
    - Changed all driver-assisted API parameters to be mandatory
    - Added validation to prevent 'force_host_assisted_migration' to be
    used alongside driver-assisted parameters
    - Changed "same host" validation to reject only if the combination
    of "host", "new_share_network" and "new_share_type" is the same as
    the source
    - Updated migration driver interfaces to support snapshots
    - Updated zfsonlinux driver, defaulting preserve_snapshots to False
    - Updated dummy driver to support preserve_snapshots

    Spec update with latest changes since [1] merged
    can be found in [2].

    APIImpact
    DocImpact

    [1] I5717e902373d79ed0d55372afdedfaa98134c24e
    [2] If02180ec3b5ae05c9ff18c9f5a054c33f13edcdf

    Change-Id: I764b389816319ed0ac5178cadbf809cb632035b4
    Partially-implements: blueprint ocata-migration-improvements

[Sneha Prasad (snpd)]

It appears to me that share_migration.rst has been already modified
accordingly. Is zfs-on-linux-driver.rst or any other file needs to be
modified too?

[Goutham Pacha Ravi (gouthamr)]

Hi Sneha,

Thanks for looking at this long-pending issue!

The specification for this feature mentions the documentation that ought to be there [1]. It doesn't have a lot of detail, but some of what it calls out has been added, see Developer Reference [2], Administrator Reference [3].

What seems to be missing is the API reference - https://developer.openstack.org/api-ref/shared-file-system/#share-migration-since-api-v2-5 is woefully out of date. If you're interested in contributing, please take a look at the share migration API and update the API reference in the manila tree. Feel free to ask questions here if you need more direction.

[1] http://specs.openstack.org/openstack/manila-specs/specs/ocata/ocata-migration-improvements.html#id1
[2] https://docs.openstack.org/manila/latest/contributor/share_migration.html
[3] https://docs.openstack.org/manila/latest/admin/shared-file-systems-share-migration.html

[Sneha Prasad (snpd)]

Hi Gautham,

I went through the documentation: https://docs.openstack.org/manila/latest/contributor/share_migration.html . Just had one question: What are the things that need to be added to the API reference? The parameter description, or the details about Share Migration driver-assisted interfaces, or is there any wrong info which I need to correct?

Thanks.

[vrushti (vrushti)]

Hi Sneha,

Can I work on this issue?

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/715290

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/715290
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=295adb71bf261bfcbc8ee41ac284901b8b9268d7
Submitter: Zuul
Branch: master

commit 295adb71bf261bfcbc8ee41ac284901b8b9268d7
Author: vrushti <email address hidden>
Date: Thu Mar 26 23:43:03 2020 +0530

    Documentation for Share Migration Ocata Improvements.

    Implemented several improvements to share migration in documentation
    according to https://review.opendev.org/#/c/406305/

    Summary of changes:

     - Add driver-assisted mandatory parameters.
     - Removed previous API documentation because support for them isn't
       there anymore after the backwards incompatible changes were
       made via https://review.opendev.org/#/c/406305/.
     - Add force-host-assisted migration.

    Change-Id: I6d446b4037a3a9991e375f0a8bfb1f6edce09c1f
    Closes-Bug: #1658230