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drive uses one channel, so each HBA port can support up to four tape drives. You can use a cable with one
connector on each end, but only one channel will be used.
Supported speeds by drive generation are shown in the table below.
Supported SAS Speeds
LTO Generation
Supported Speeds
LTO-6
1.5 Gbps, 3 Gbps, 6 Gbps
LTO-7
1.5 Gbps, 3 Gbps, 6 Gbps
LTO-8
1.5 Gbps, 3 Gbps, 6 Gbps
CAUTION
High quality SAS cables rated at the transfer rate the SAS drives are
required. Always verify that the SAS cable you are using is rated for the
data transfer speed of the interface of your components. SAS cables
described as "equalized" may not support 6 Gb/s data rates and should
not be used with LTO-5 or later generation tape drives unless these
cables are verified for 6 Gb/s data rates.
CAUTION
The library has one or more mini-SAS connectors on each SAS tape
drive. Mini-
SAS connectors are keyed. Do not force a SAS cable’s mini-
SAS connector into the tape drive as it might be keyed differently.
A SAS tape drive is identified by a unique identifier called a
W
orld
W
ide
N
ame (WWN) or
W
orld
W
ide
Id
entifier (WWID). The library assigns the WWID to the drive bay. When a tape drive is replaced, the WWID
is re-assigned to the new tape drive.
The operating system tracks the WWID for the tape drive on each HBA channel. Each of the drive
connectors on the fan-out cable is associated with an HBA channel. Once a tape drive has been plugged
in, it should remain on the same channel to retain the association between the HBA channel and WWID.
Fibre Channel Configuration Requirements
The
F
ibre
C
hannel (FC) tape drive can be connected directly to the server with a
H
ost
B
us
A
dapter (HBA)
or through a storage area network (SAN).
The installation requires one Fibre Channel cable for each tape drive. The tape drives all utilize an LC-
style connector. Some drives will have two FC ports, but only one cable connection is needed per drive.
The cable can be connected to either drive FC port.
Supported speeds by drive generation are listed in the table below.
Table 1: Supported Fibre Channel Speeds
LTO Generation
Supported Speeds
LTO-6
2 Gbps, 4 Gbps, 8 Gbps
LTO-7
2 Gbps, 4 Gbps, 8 Gbps
LTO-8
2 Gbps, 4 Gbps, 8 Gbps
NOTE
▪
Use an appropriate HBA for your tape drive due to performance
requirements.
A lower Gbps HBA might result in performance degradation when moving
highly compressible data to a higher Gb tape drive.
▪
In a SAN installation, all switches between the host and the library must be of
the appropriate type.
A lower Gb switch in the path may result in performance degradation.
Configure zoning so only the backup servers may access the library.
