enough data for the tape drives to write at full speed. Find the performance impact of your system's
disk connection in Table 29.
Table 29 Performance impact of various disk connections
RecommendationsPerformance impactConnection type
For good performance, use a
faster connection with LTO-3,
LTO-4, and LTO-5 tape drives.
• LTO-2: GOOD. When fully used, a 1 Gb fibre
connection can provide enough bandwidth for
two LTO-2 tape drives.
• LTO-3, LTO-4, LTO-5: POOR. A 1 Gb fibre
connection is inadequate for an LTO-3, LTO-4,
or LTO-5 tape drive.
Fibre: 1 Gb
For good performance, use a
faster connection if you have
multiple LTO-3 or LTO-4 tape
drives, or an LTO-5 tape drive.
• LTO-2: GOOD. When fully used, a 2 Gb fibre
connection can provide enough bandwidth for
4 LTO-2 tape drives.
• LTO-3: GOOD. When fully used, a 2 Gb fibre
connection can provide enough bandwidth for
an LTO-3 tape drive.
• LTO-4 HH: GOOD. When fully used, a 2 Gb
fibre connection can provide enough bandwidth
for an LTO-4 HH tape drive.
• LTO-5: POOR. A 2 Gb fibre connection is inad-
equate for an LTO-5 tape drive.
Fibre: 2 Gb
GOOD. When fully used, a 4 Gb fibre connection
can provide enough bandwidth for the following
number of tape drives:
• LTO-2: 8
• LTO-3 HH: 4
• LTO-4 HH: 2
• LTO-5: 1
Fibre: 4 Gb
GOOD. When fully used, an 8 Gb fibre connection
can provide enough bandwidth for the following
number of tape drives:
• LTO-2: 16
• LTO-3 HH: 6
• LTO-4 HH: 3
• LTO-5: 2
Fibre: 8 Gb
GOOD. When fully used, a 3 Gb high-performance
RAID array can support up to the following number
of tape drives:
• LTO-2: 10
• LTO-3, LTO-4: 6
• LTO-5: 3
SAS: 3 Gb
Troubleshooting120