Notwithstanding the possiblity of a hardware level problem the fractured block entry sounds like a device is being used in multiple places. The last time we encountered a problem like this was when we accidentally got the voting devices mixed up in multiple nodes and it ended up mapping to a data file in one of the other nodes (on Solaris). More esoteric possiblities may exist such as oracle bugs that are allowing dirty reads and such but the fractured block sounds like a device or device blocks are cross mapped for some odd reason. More experienced folks may have a specific answer to guide you Regards -Krish -- //www.freelists.org/webpage/oracle-l