CapabilitiesFilter breaks the multi-backend and QoS support

[Vincent Hou]

In order to support multi-backend, we need to configure with volume type with different extra-specs.
QoS support can also be enabled with volume type plus a certain extra specs.

However, if CapabilitiesFilter exists in scheduler_default_filter, the scheduler will not return any valid host, so that the volume is unable to create.

If we remove CapabilitiesFilter from the scheduler_default_filter, the issue disappears.

I am using the latest code. This bug can be reproduced by the following steps:

=======================================================================================
1. Create a volume type: cinder type-create test_type

2. Associate this volume type with an extra spec for the volume_backend: cinder type-key test_type set volume_backend_name=LVM_iSCSI

3. Configure cinder to support multi-backed in cinder.conf:

enabled_backends=lvm1,nfs1
[lvm1]
volume_driver=cinder.volume.drivers.lvm.LVMISCSIDriver
volume_backend_name=LVM_iSCSI
[nfs1]
nfs_shares_config=${PATH_TO_YOUR_SHARES_FILE}
volume_driver=cinder.volume.drivers.nfs.NfsDriver
volume_backend_name=NFS

4. Create a volume: cinder create 1 --volume-type test_type.

The scheduler will not find a valid host.
========================================================================================

[Huang Zhiteng (zhiteng-huang)]

I can't reproduce this. And what does this has to do with QoS?

[John Griffith (john-griffith)]

Works for me as well, and I'd have to echo "What does this have to do with QoS"?

[John Griffith (john-griffith)]

@Vincent,
Are you maybe using unscoped keys for vendor unique info? I'm going to mark this as invalid, let me know if there's more detail or something that we're missing.

Thanks!