ECS: Hybrid CAS migration using transformation and ECS Sync can result in clips missing BLOBs

CAS migration using Native Transformation to cut-over the application to ECS while ECS Sync migrates data can result in clips missing BLOBs on ECS.

Attempts to read these clips from ECS results in an -10014 FP_FILE_NOT_STORED_ERR error for all clips migrated.

ECS Sync shows that all objects have been migrated and that verification for these objects is passed.

The problem with this process is that ECS Sync does not know that Transformation is running. During the normal Blob Existence Check, ECS says that the BLOB exists, even though it has not been written (because that is how Transformation behaves). So ECS Sync does not write the BLOB (for efficiency). Then, in the verification process, it reads back the BLOB to verify the data, which works because Transformation pulls it back from Centera. The result is that the clip data formats (CDFs) all get transferred but none of the BLOB data gets written, and verification succeeds because Transformation pulls the Blobs back from Centera.

ECS Sync 3.2.7 code was used for the migration and wrote the clip information but did not write the BLOB data. ECS Sync did not cause any data integrity issues but did not migrate all portions of the data. The Force Sync option was used with ECS Sync believing that this forces the writing of BLOB data. ECS Sync code (3.2.7) still checks for BLOB data, regardless of the Force Sync option. Since transformation finds the BLOBs on Centera, the BLOBs do not get written even when using Force Sync.

Dell has corrected this issue in ECS Sync 3.2.8 and later versions to ensure that when the Force Sync option is set that it does not check for BLOB data but writes the CDF and BLOB data.