Comment 8 for bug 1794827

Reviewed: https://review.opendev.org/694357
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=c55eff39f22bec875d7be296fef7f72585689729
Submitter: Zuul
Branch: stable/queens

commit c55eff39f22bec875d7be296fef7f72585689729
Author: Matt Riedemann <email address hidden>
Date: Wed Oct 3 10:27:22 2018 -0400

    doc: fix and clarify --block-device usage in user docs

    The docs on create a volume-backed server from the command
    line were wrong in a few ways:

    * The openstack server create command does not currently allow
      booting from a volume where a source image is provided and
      nova creates the volume from the image and uses that volume
      as the root disk. The nova boot command supports that, so the
      docs are updated to call out the nova boot command since that
      is the appropriate command in this case (even the syntax with
      the openstack server create --block-device was wrong).

    * When creating a server from a bootable volume with the OSC CLI,
      either the --volume or --block-device options should be used
      for a single volume, but not both. The docs were using both, so
      the latter is dropped and a note is added which links to the CLI
      documentation for more details on --block-device option usage.

    Change-Id: I985b870759d6c21ef9357b04f39099c02354f135
    Closes-Bug: #1794827
    (cherry picked from commit 16027094ebabc5cd9f2e766431f18aadeff54a40)
    (cherry picked from commit 6a6d0e943443a9cdd9b56aa9a93768d05e4dde0e)