A technique includes writing blocks of data from a plurality of servers to
an array of disks that are shared in common by the servers. Prior to the
writing in each block of data to the array of disks, the method includes
storing in a journal a copy of the block of data to be written to the
array of disks. Also stored in the journal is at least one header, and
this header(s) indicates that the copy was successfully stored in the
journal.