Fibre Channel Connections; Fibre Channel Loop Configurations; Direct (Out-Of-Band) Managed Storage Subsystems - IBM TotalStorage DS4100 Installation, User's, And Maintenance Manual

Figure 24. Direct (out-of-band) managed storage subsystems

Fibre channel connections

The storage server fibre channel connection consists of up to four host
fibre-channel loops and a redundant drive fibre-channel loop. The host fibre-channel
loops provide the fibre path for host attachment. They can consist of fibre-channel
cables, SFPs, host bus adapters, fibre-channel switches, and RAID controllers. The
redundant drive fibre-channel loop provides the fibre path to the hard disk drives
(HDDs). The redundant drive fibre-channel loop consists of fibre channel HDDs and
optional storage expansion units, fibre-channel cables, and SFPs.
Exception: The DS4100 single-controller storage server does not support drive
loops or expansion units.
The DS4100 base storage server supports redundant disk-drive-loop configurations.
Each RAID controller has three SFP ports. These SFP ports are labeled Host 1,
Host 2, and Expansion. You can build a redundant drive loop by connecting one or
more expansion units to the redundant RAID controllers. Then, use dual fiber-optic
cables to connect one expansion unit to another in a daisy-chain. For more
information about adding expansion units, see "Connecting expansion units (base
storage server only)" on page 57.

Fibre channel loop configurations

You must determine how the host systems will connect to the storage server. You
can connect up to two host systems directly to the storage server, or you can
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IBM TotalStorage DS4100 Storage Server: Installation, User's, and Maintenance Guide
Controller
Controller
Controller
Controller
Storage subsystems
Ethernet
Host computer
Fibre Channel
I/O path
Note: The client software is
installed on one or more
management systems,
or on the host computer.
Management station