Overview Of The Cci Software Environment - Hitachi VSP F1500 User And Reference Manual

Overview of the CCI software environment

The CCI software environment includes components on the Hitachi RAID
storage systems and the CCI software on the host servers and/or on the
Storage Navigator computer or management client. The CCI components on
the storage systems include the user data volumes and CCI command
devices.
Each CCI instance on a host server includes:
• CCI application files, referred to as HORC Manager (HORCM):
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• Configuration definition file (user-defined)
• User execution environments for the HDS features, including the
commands, a command log, and a monitoring function.
The CCI commands also have interface considerations (see
command interface on page
CCI components on the RAID storage system
Command device
CCI commands are issued by the CCI software to the RAID storage system
command device. The command device is a user-selected, dedicated logical
volume on the storage system that functions as the interface to the CCI
software on the host. The command device is dedicated to CCI
communications and cannot be used by any other applications. The command
device accepts CCI read and write commands that are issued by the storage
system. The command device also returns read requests to the host. The
volume designated as the command device is used only by the storage
system and is blocked from the user. The command device uses 32 MB, and
the remaining volume space is reserved for CCI and its utilities. The
command device can be any OPEN-x device (for example, OPEN-V) that is
accessible to the host. A LUN Expansion volume cannot be used as a
command device. A Virtual LVI/Virtual LUN volume as small as 36 MB (for
example, OPEN-3-CVS) can be used as a command device.
WARNING: Make sure the volume to be selected as the command device
does not contain any user data. The command device will be inaccessible to
the host.
The CCI software on the host issues read and write commands to the
command device. When CCI receives an error notification in reply to a read or
write request to the RAID storage system, the CCI software switches to an
alternate command device, if one is defined. If a command device is blocked
2-2
Log and trace files
A command server
Error monitoring and event reporting files
A configuration management feature
CCI software environment
Command Control Interface User and Reference Guide
2-7).
CCI and the SCSI