[LU-4870] LFSCK3: Race between layout LFSCK and metadata migration

• Type: Bug
• Resolution: Fixed
• Priority: Critical
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.6.0
• Labels: MB
• Severity: 3
• Assignee: nasf (Inactive)
• Reporter: nasf (Inactive)

Description

According to current metadata migration implementation, before the old MDT-object is removed, both the new MDT-object and old MDT-object will reference the same LOV layout. Then if the layout LFSCK finds the new MDT-object by race, it will regard related OST-object(s) as multiple referenced case, and will try to create new OST-object(s) for the new MDT-object.