Asset/Flow Upload to IGC Fails with 403: The Session [...] Has Expired or Was Not Found

Problem

The last step (upload of the lineage to IGC) of Manta Flow for IGC occasionally fails with the following error in any of the *IgcUploadMetadataMasterScenario_*properties.log log files.

2017-04-18 09:27:44.372 [pool-2-thread-1] INFO  eu.profinit.manta.dataflow.igc.common.UploadModelTask - Deleting old script assets (0).
2017-04-18 09:27:44.481 [pool-2-thread-1] INFO  eu.profinit.manta.dataflow.igc.common.UploadModelTask - Inserting assets.
2017-04-18 09:59:54.107 [pool-2-thread-1] INFO  eu.profinit.manta.dataflow.igc.common.UploadModelTask - Inserting flows.
2017-04-18 10:00:26.930 [pool-2-thread-1] ERROR eu.profinit.manta.connector.http.caller.callback.BasicErrorCallback - Response 403: {"httpStatus": 403, "msgId": "CDISF0004E", "msgSeverity": "Error", "msgText": "The session [c01ddc20-b22f-4367-9fa0-537c1903daa7] has expired or was not found."}

The error occurs when the upload of assets takes longer than the session timeout. The subsequent upload of flows fails immediately.

Additional Information

Based on the information about Changing Timeout Values to Allow Import of Large Files to InfoSphere Business Glossary or to InfoSphere Information Governance Catalog in IBM's knowledge base, additional detailed information about the error is available in the Websphere log files SystemOut.log, SystemError.log, and igc.log. The location of these log files in the filesystem is described in detail in IBM Technote InfoSphere Information Governance Catalog: log files.

Solution

Investigate the error message in the abovementioned log files and: