Created attachment 1247126 [details]
engine log

Description of problem:
Failed to retrieve VMs and Templates from the OVF disk of Storage Domain data.

VMs are gone after storage domain was detached and imported back to the system.
There are no VMs on the 'VM Import' subtab list. And i got the next warning:

'Failed to retrieve VMs and Templates from the OVF disk of Storage Domain data2.'

2017-02-02 14:02:26,108+02 WARN  [org.ovirt.engine.core.bll.storage.disk.image.GetUnregisteredDiskQuery] (default task-7) [4764e9b9-8cde-496e-bbe0-a72497d05795] Exception while parsing JSON for disk. Exception: '{
}': org.codehaus.jackson.JsonParseException: Unrecognized token 'None': was expecting 
 at [Source: java.io.StringReader@3bf9f654; line: 1, column: 9]
        at org.codehaus.jackson.JsonParser._constructError(JsonParser.java:1433) [jackson-core-asl.jar:1.9.13.redhat-3]



2017-02-02 14:02:26,997+02 ERROR [org.ovirt.engine.core.bll.storage.domain.AttachStorageDomainToPoolCommand] (default task-7) [2dd528ad] Image data could not be retrieved for disk id '69caa180-4807-433d-b229-c66ad5e2a1c0' in storage domain id '40b3e690-4b26-481e-be7d-4dfb303a8660'
2017-02-02 14:02:27,011+02 WARN  [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (default task-7) [2dd528ad] EVENT_ID: RETRIEVE_OVF_STORE_FAILED(1,017), Correlation ID: null, Call Stack: null, Custom Event ID: -1, Message: Failed to retrieve VMs and Templates from the OVF disk of Storage Domain data2.

Version-Release number of selected component (if applicable):
4.1.0.3-0.1.el7

How reproducible:
No idea. It is the second time it happens to me. No idea how to reproduce it.

Steps to Reproduce:
1. Create few VMs with disks on a data domain
2. Detach data domain from DC and import back

Actual results:
From time to time the VMs are failed to be retrieved.

Expected results:
Should work as expected.