An error has been encountered when attempting to read a page from the specified database volume.
The failed I/O operation is retried on a mirrored volume, if available.
See accompanying messages for information about the volume in error. If the error persists and another mirrored copy of the volume is available, the failing volume should be taken offline by using the VARY OFF command, and repaired. Otherwise, halt the server and repair the volume. Then restart the server.