A method to copy information to two data storage devices. The method
provides a first data storage device and a second data storage device,
where the first data storage device is capable of communicating with the
second data storage device. The method provides first information and a
write command to the first data storage device at a first time. The
method determines if the write command comprises a synchronous copy
attribute. If the write command comprises a synchronous copy attribute,
then the method synchronously provides the first information to the
second data storage device. Alternatively, if the write command does not
comprise a synchronous copy attribute, then the method provides the first
information to the second data storage device at a second time, where
that second time is later than the first time.