Hi!
As customer is facing a strange problem during VSS snapshot creation. We have created a trace with vsstrace.exe and the log shows that it times out after sending the 0x53c008 control code, which seems to be related to snapshot preparation.
Anyone has eventually an idea what this control code does? Some are documented and show up in the DDK’s header files but this one is not. It is function 2. It eventually times out after around 20 minutes in our case and then the semaphore timed out error is reported back to the application trying to do the snapshot, in this case the Windows built-in MMC computer management snap-in that we use to create a snapshot. The volume that we try to snapshot s on a storage system connected over iSCSI.
I could find 4 defined macros:
IOCTL_VOLSNAP_FLUSH_AND_HOLD_WRITES → Function 0
IOCTL_VOLSNAP_RELEASE_WRITES → Function 1
IOCTL_VOLSNAP_COMMIT_SNAPSHOT → Function 4
IOCTL_VOLSNAP_END_COMMIT_SNAPSHOT → Function 5
Thanks for any info!
Andreas