libvirt: find-storage-pool-sources work unexpected

[Royce Lv]

1. how to reproduce:
    virsh find-storage-pool-sources-as netfs localhost

2. frequency:
    100%

3. expected result:
    list export paths of localhost

4. Actul result:
    virsh # find-storage-pool-sources-as netfs localhost
error: Failed to find any netfs pool sources
error: Cannot find '' in path: No such file or directory

5. Source code trace:
    In src/storage/storage_ backend_fs.c:

        if (source->nhost != 1) {
        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                       _("Expected exactly 1 host for the storage pool"));
        goto cleanup;
    }

    state.host = source->hosts[0].name;

    cmd = virCommandNewArgList(SHOWMOUNT,
                               "--no-headers",
                               "--exports",
                               source->hosts[0].name,
                               NULL);

6. diagnose suggestion:
    It may because the build machine does not has a nfs-common installed, so SHOWMOUNT during configure, is configured as empty.
   So when running find-source cmd, SHOWMOUNT cannot be found so report error.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: libvirt-bin 1.0.2-0ubuntu11.13.04.4
ProcVersionSignature: Ubuntu 3.8.0-32.47-generic 3.8.13.10
Uname: Linux 3.8.0-32-generic x86_64
ApportVersion: 2.9.2-0ubuntu8.5
Architecture: amd64
Date: Mon Dec 30 17:05:07 2013
InstallationDate: Installed on 2013-10-06 (84 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
MarkForUpload: True
SourcePackage: libvirt
UpgradeStatus: No upgrade log present (probably fresh install)

[Serge Hallyn (serge-hallyn)]

Thanks, adding nfs-common to build-deps seems reasonable.
 status: triaged
 priority: wishlist

[Royce Lv (lvroyce-4)]

Thanks or providing feedback, as this bug affect multiple Ubuntu version and easy to fix, would you pls tell me when it will be available? So that we can adjust our product feature release plan.

[Serge Hallyn (serge-hallyn)]

As this is a new feature, it will not be enabled for prior versions. However it should be fixed today in trusty.

[Royce Lv (lvroyce-4)]

Thanks for your quick response Serge.
By "new feature" do you mean find-storage-pool-source?
As I went through libvirt git log and find it was supported by libvirt early in 2008:
39c9354c src/storage_backend_fs.c (Daniel P. Berrange 2008-08-27 20:05:58 +0000 1304) .findPoolSources = virStorageBackendFileSystemNetFindPoolSources,

So I think ealier Ubuntu libvirt version also be affected, even earlier than my 13.04.

[Launchpad Janitor (janitor)]

This bug was fixed in the package libvirt - 1.2.1-0ubuntu3

---------------
libvirt (1.2.1-0ubuntu3) trusty; urgency=medium

  * d/control: add nfs-common to build-deps (LP: #1264955)
 -- Serge Hallyn <email address hidden> Wed, 22 Jan 2014 08:56:01 -0600

[Serge Hallyn (serge-hallyn)]

Quoting Royce Lv (<email address hidden>):
> Thanks for your quick response Serge.
> By "new feature" do you mean find-storage-pool-source?
> As I went through libvirt git log and find it was supported by libvirt early in 2008:
> 39c9354c src/storage_backend_fs.c (Daniel P. Berrange 2008-08-27 20:05:58 +0000 1304) .findPoolSources = virStorageBackendFileSystemNetFindPoolSources,
>
> So I think ealier Ubuntu libvirt version also be affected, even earlier
> than my 13.04.

Enabling a new feature in a stable release isn't usually allowed
regardless of whether upstream had support for it or not.

We could try for an exception if it is important to you - please
see https://wiki.ubuntu.com/StableReleaseUpdates.