When restoring a raw device from an image level backup, the restore runs and succeeds, but no data appears to have been actually restored.
An issue has been found with the image level restore of raw partitions where after the restore completes successfully, no data appears to be on the restored device. This is because Linux tends to cache reads from the device and will not display the restored data until after clearing the disk cache.
To access the data restored to the raw device, use the hdparm command to flush the disk cache in the OS. The syntax for this command is "hdparm -f /dev/sdAN" where A = the device node, and N = the partition on that node.
For example, after running an image level restore to raw device /dev/sda2, run the command "hdparm -f /dev/sda2" prior to accessing the newly restored data on the /dev/sda2 device.
An enhancement request has been submitted to have the disk cache flushed automatically upon completion of the restore, in a future release.
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