Host Channels And Drive Channels - Quantum StorNext QD7000 Hardware Manual

8 | Hardware Cabling Guide
Term used for E2700 and
E5600 storage arrays, and
EF560 flash arrays
controller canister
ESM (environmental service
module)
power-fan canister
Keep in mind that some drive shelves (drive trays) can be used with E2800 controller shelves as well
as with other controller-drive trays. The terminology that applies for this hardware depends on the
context in which it is used. Where either terminology might apply, this document uses the newer
terminology. The first occurrence of the term is followed by the alternative term in parentheses — for
example, controller shelf (controller-drive tray).
The controllers configure, access, and manage the storage capacity of the drives in the controller
shelf (or controller tray) and the storage capacity of the drives in any attached drive shelves (or drive
trays). The controllers also support connections to hosts. A controller shelf with, optionally, any
attached drive shelves (drive trays) comprise a storage array. With SANtricity System Manager, you
manage a storage array through a web interface from a computer with an Ethernet connection to the
controller shelf. With SANtricity Storage Manager, you manage a storage array through an attached
host, called the management station.
A controller shelf (controller-drive tray) can be attached to one or more expansion drive shelves (or
drive trays) to increase the capacity of a storage array or to increase the redundancy of volume groups
or disk pools in the storage array. The controllers can configure, access, and manage the storage
capacity of the drives in the attached drive shelves or drive trays. Expansion ports on the controllers
connect to drive ports on the environmental services modules (ESMs) of the drive trays or the I/O
modules (IOMs) in the drive shelves. A drive tray or drive shelf can connect to controllers indirectly
through another drive tray or drive shelf.

Host channels and drive channels

In this document, the term
between a host and a controller shelf (controller-drive tray), or between drive shelves (drive trays)
and an attached controller shelf. A data path from a host to a controller shelf is a
channel might be Fibre Channel, InfiniBand, iSCSI, or SAS. A path from a drive shelf to a controller
shelf is a drive channel . Each drive channel is defined by a series of SAS devices connected through
expanders.
In an E2700 controller drive tray or an E2800 controller shelf, each controller has one drive channel
along with an internal SAS expander (switch) that enables both drive ports on the controller to share
that channel. Other models of controller shelf use direct port connections. With direct port
connections, there is a one-to-one correspondence between ports and channels.
When you mix different types of drive shelves, you must consider the total number of drive
Note:
bays that are available in the final configuration of the storage array. Your configuration must meet
both the limit on the total number of drive bays and the limit on the number of shelves in the
storage array.
Term used for E2800 storage
arrays
controller canister
IOM (I/O module)
power-fan canister
channel refers to a path for the transfer of data and control information
Definition
The component in a controller-
drive tray or controller shelf
that includes a controller card,
a battery, and–optionally–a
host interface card.
The component in a drive tray
or drive shelf that manages the
activities performed by the
enclosure.
The component in a 12-drive
or 24-drive enclosure that
includes the power supply (or
PSU) and an integrated fan.
host channel . A host