Installation guide

Storage Subsystem
Storage Subsystem
Components
Each system has a storage subsystem, which consists of mass
storage adapters and mass storage devices.
An expander cabinet allows you to place additional mass storage
near the system.
Mass Storage
Adapters
Your system has five adapters built into the I/O module. The
adapters provide a path to each mass storage bus through which
the CPU can communicate with mass storage devices.
Each of the five adapters can support up to eight nodes. The
adapter and each device count as one node; hence, each adapter
can support seven storage devices.
DSSI adapters allow you to link one system to another to form a
DSSI VMScluster configuration. When a DSSI bus is extended to
a second system, both systems can share up to six DSSI storage
devices.
Mass Storage
Devices
Mass storage devices record data on media. Use mass storage
devices to store data and software permanently. When the data
or software is needed, the CPU copies it from the mass storage
device into main memory. The two primary types of mass storage
devices are fixed-media devices, such as fixed-disk drives and
removable-media devices, such as tape cartridges and compact
discs.
Mass Storage
Expansion
Enclosure
You can expand mass storage capacity on a DEC 4000 AXP
system by connecting it to a mass storage expander, such as the
R400X or SF100.
The R400X expander provides space for up to seven additional
RZ-series or RF-series drives, or up to six of these drives and a
tape drive. Using R400X expanders, your system can connect to
up to 35 devices.
7–10 Learning More About Your System