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[Dan Genin <daniel.genin@xxxxxxxxxx>]

Public bug reported:

Attempting to boot an LVM backed instance that exceeds available disk
space results in ProcessExecutionError exception leading to an ERROR
state instead of clean termination.

Observed in Nova 209c0a29 on DevStack b160640d. To generate the failure
configure Nova for LVM ephemeral storage with

[libvirt]
images_volume_group = nova-lvm
images_type = lvm

Make the nova-lvm volume relatively small, say 5G, and boot an m1.small
instance.

Exception back trace is as follows: http://pastebin.com/ePG3s58P.
----------------------------------------------------------------

It is not entirely clear why the booting process is allowed to get as
far as actually attempting to create instance disk since the scheduler
really should return 0 matching hosts, as the disk is obviously too
small.  However, once create_lvm_image() raises "RunTimeError:
Insufficient Space on Volume Group nova-lvm. ...", the booting process
attempts to recover gracefully by terminating the instance. At some
point in the termination the (non-existent) instance volume is cleared,
resulting in an execution of 'nova-rootwrap /etc/nova/rootwrap.conf
blockdev --getsize64 /' , which does not match any of the root-wrap
filters and generates ProcessExecutionError.

** Affects: nova
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/1325051

Title:
  Booting LVM instance too big for the volume generates an exception

Status in OpenStack Compute (Nova):
  New

Bug description:
  Attempting to boot an LVM backed instance that exceeds available disk
  space results in ProcessExecutionError exception leading to an ERROR
  state instead of clean termination.

  Observed in Nova 209c0a29 on DevStack b160640d. To generate the
  failure configure Nova for LVM ephemeral storage with

  [libvirt]
  images_volume_group = nova-lvm
  images_type = lvm

  Make the nova-lvm volume relatively small, say 5G, and boot an
  m1.small instance.

  Exception back trace is as follows: http://pastebin.com/ePG3s58P.
  ----------------------------------------------------------------

  It is not entirely clear why the booting process is allowed to get as
  far as actually attempting to create instance disk since the scheduler
  really should return 0 matching hosts, as the disk is obviously too
  small.  However, once create_lvm_image() raises "RunTimeError:
  Insufficient Space on Volume Group nova-lvm. ...", the booting process
  attempts to recover gracefully by terminating the instance. At some
  point in the termination the (non-existent) instance volume is
  cleared, resulting in an execution of 'nova-rootwrap
  /etc/nova/rootwrap.conf blockdev --getsize64 /' , which does not match
  any of the root-wrap filters and generates ProcessExecutionError.

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