2465552 - Dual stack upgrade: SUM fails during PREP_INIT/SETSYNC_PREP_STARTED phase with error : "No synchronization mechanism available"

During upgrade of your Dual stack system like PI system, ABAP stack of SUM fails during PREP_INIT/SETSYNC_PREP_STARTED phase with the following error:"No synchronization mechanism available"

1 ETQ201 Entering upgrade-phase "PREP_INIT/SETSYNC_PREP_STARTED" ("20170405195620")
2 ETQ367 Connect variables are set for standard instance access
4 ETQ399 System-nr = '00', GwService = 'sapgw00' Client = '000'
4 ETQ399 Environment variables:
4 ETQ399 dbs_ora_schema=SAPSR3
1 ETQ200 Executing actual phase 'PREP_INIT/SETSYNC_PREP_STARTED'.
1 ETQ399 Phase arguments:
2 ETQ399 Arg[0] = 'PREPARE'
2 ETQ399 Arg[1] = 'STARTED'
1EETQ399 Last error code set is: No synchronization mechanism available
1EETQ204 Upgrade phase "SETSYNC_PREP_STARTED" aborted with severe errors ("20170405195620")

You have already checked below KBA which were not applicable in your scenario: you have started with correct URL and its not splitted still a valid dual stack system 

KBA 2312141 - SUM - SETSYNC_PREP_STARTED : No synchronization mechanism available

KBA 2297309 - No synchronization mechanism available

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• Upgrade of Dual stack system like PI with NW release <= 7.4
• All version of SUM 

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Software Provisioning Manager , Dual-Stack Split Procedure ,  SAP Process Integration (PI) , SAP Process Orchestration 7.5 , KBA , BC-UPG-TLS-TLA , Upgrade tools for ABAP , BC-UPG-TLS-TLJ , Upgrade tools for Java , Problem