Hi Subhasish and sorry for my late answer.
OS is 2012 R2 with latest updates.
Storage array is EMC Symmetrix VMAX, thin provisioned.
When I am trying to use defrag via defrag.exe or Optimize-Volume and disk is in redirected mode, if I try to -ANALYZE only, it will fail. Slab Analysis (which is run as part of -analyze process) will return "The specified extrinsic Method does not exist" so command is cancelled.
If I tried to use -Defrag param instead of -Analyze, where slab analysis is not used I suppose (-Verbose doesn't mention SLAB Analysis is run in this case), command completes successfully.
In short, defrag analysis (Optimize-Volume -Analyze) is not possible in normal or redirected mode. Only maintenance mode allows to pass defrag analysis successfully. But if I use defragging without analyzing disk (Optimize-Volume -Defrag), it completed successfully, perhaps because there is no "Slab Analysis" used which seems to be root cause.
If Defrag GUI is used, it is not possible to Analyze and also Defrag disks in Redirected mode. It seems it is because GUI forces -analyze all the time before "-defrag only" is applied so GUI is useless here.
About SCOM: I mentioned it because it checks disks for fragmentation so (Optimize-Volume -Analyze equivalent) is used to detect if disk is fragmented. This can't complete successfully because of the bug mentioned above, also in case disk is in "redirected mode".
Thanks for any feedback
Filip