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problem troubleshooting in the event of an error. If the ones digits are not unique,
two or more devices will have the same hard AL_PA. In such a case, the DS5100
and DS5300 controller will use soft AL_PAs for the devices that have identical hard
AL_PAs.
The problem with soft addressing is that addresses may change between LIPs. This
possibility increases the difficulty of troubleshooting drive channel problems, since
one cannot easily ascertain whether the same device with a different address or a
different device may be causing a problem.
Fibre channel loop and ID settings
When you install a hard disk drive in the storage expansion enclosure, the drive
tray plugs into a printed circuit board called the
midplane
. The midplane sets the
fibre channel loop ID automatically, based on the enclosure ID switch setting and
the physical location (bay) of the hard disk drive.
DS Storage Manager client host port numbering
The following notes describe the host port numbering convention used by the DS
Storage Manager client to identify the host ports in controller A and controller B.
The DS Manager client host port numbering is different from the port numbering on
the HIC face plate.
v
Host ports are numbered from right to left in controller A, starting with 1, 2, and
so on for each port. The right-most port of the HIC in slot 1 is identified as port 1
by the Storage Manager.
v
Host ports are numbered from left to right in controller B, starting with 1, 2, and
so on for each port. The left-most port of the HIC in slot 1 is identified as port 1
by the Storage Manager.
v
Currently, the last port in either controller A or B is identified as either port 2, 4, 6
or 8, depending on the number and type of host cards installed.
v
The exception is that the iSCSI port configuration window starts counting with the
iSCSI port only. In the case of mixed FC and iSCSI HICs with the iSCSI HIC
installed in slot 2, the iSCSI port configuration window identifies them as ports 1
and 2, regardless of the number of Fibre Channel host ports in the HIC installed
in slot 1.
Connecting hosts directly to the DS5100 and DS5300 Fibre Channel
host ports
The DS5100 and DS5300 supports redundant direct connections to up to eight
hosts. To ensure full protection against the loss of any one fibre channel path from
the host servers to the DS5100 and DS5300, always use redundant host
connections by connecting each host to the appropriate single-ported host channels
on both RAID controllers A and B.
To connect a host adapter to the DS5100 and DS5300 RAID controllers, perform
the following steps:
1. Install SFP modules in host ports on RAID controllers A and B.
Note:
The alignment of the single-ported host channels on controller A are
opposite those of controller B. Before inserting an SFP module into a
host port, verify that the SFP module is rotated correctly to match the
alignment of the host port on the RAID controller. Do not force-fit.
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IBM System Storage DS5100 and DS5300 Storage Subsystem: Installation, User’s, and Maintenance Guide