nova.image.glance.download failure error message is insufficient

[Joe Julian]

2015-03-12 22:48:27.941 18501 TRACE nova.image.glance File "/opt/io/io-nova/lib/python2.7/site-packages
/nova/image/glance.py", line 371, in download
2015-03-12 22:48:27.941 18501 TRACE nova.image.glance data.write(chunk)
2015-03-12 22:48:27.941 18501 TRACE nova.image.glance IOError: [Errno 28] No space left on device

This is not enough data to properly diagnose the problem.

In this example, glance and nova were using ceph. The expectation was that the storage devices that would be involved would all be ceph rbds. Since there was plenty of space in ceph, this error was not useful.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/164039

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/164039
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=eeea6092ff3fce3ace3deceaef1480af17ae7a01
Submitter: Jenkins
Branch: master

commit eeea6092ff3fce3ace3deceaef1480af17ae7a01
Author: Joe Julian <email address hidden>
Date: Thu Mar 12 17:38:01 2015 -0700

    log meaningful error message on download exception

    This changes:
        "IOError: [Errno 28] No space left on device"
    to read (for example):
        "Error writing to
    /var/lib/instances/_base/89e3812ae38b76b8f658e56a75f584de3bfb6941.part:
    IOError: [Errno 28] No space left on device"

    Co-Authored-By: Michael Still (<email address hidden>)
    Change-Id: I86305d100513b7f9c8cf50f5432524ec45460617
    Closes-Bug: 1431631