In a virtualization system, physical volumes are virtualized between
servers and storage systems such that even when high-performance
functions including a remote copy are provided, a virtualization unit
does not become a bottleneck of processing. For this purpose, a
virtualization node to conduct virtualization includes at least one
virtualization switch which receives data from a server and converts the
data into data for a real volume to send the data to an associated
storage and which receives data from a storage and converts the data into
data from a virtualized volume to send the data to a server and at least
one virtualization server which receives data requiring processing such
as a remote copy from the virtualization switch, performs a particular
processing for the data, and then transmits the data via the switch to a
server or a storage.