Western Digital Ultrastar Data60 Installation Manual page 68

Installation Guide
Type
Passive
HD Mini-SAS to HD Mini-SAS
Passive
HD Mini-SAS to HD Mini-SAS
Active Cables
When daisy-chaining multiple Ultrastar Data60 enclosures together, active cables must be used between
enclosures for improved signal integrity.
Passive Cabling
As a best practice, Western Digital requires connecting the cables to every other SAS connector port when
connecting more than one host per IOM. Please refer to
Order (page 61) for port connection ordering required for IOMA and IOMB:
Table 28: Recommended IOM Port Connection Order
IOM
A
B
Edge Buffering
Edge buffering is an enclosure feature that increases the overall performance when a 6Gb/s target is
connected. With edge buffering disabled, primitives that can be deleted from the initiator are added to
slow the effective logical rate to the slowest target device connected between the initiator and the target
device. With edge buffering enabled, the expanders buffer data from slower 6Gb/s targets to utilize the
12Gb/s link from the expander to the initiator in a more efficient manner.
Length
2m
3m
1st Host 2nd Host
A6 A4
B1 B3
Manufacturer
Amphenol
CS Electronics
DSC
FCI
Molex
TMC
Amphenol
CS Electronics
FCI
Molex
Table 28: Recommended IOM Port Connection
3rd Host 4th Host
A2 A5
B5 B2
5. Installation
5.4 SAS Cabling
Vendor Part Number
601760006
12G-HD-4444/2M
C5555-2M
10112041-2020LF
10117949-2020LF
1110751002
C5555-2M
601760008
12G-HD-4444/3M
10112041-2030LF
10117949-4030LF
1110751003
5th Host 6th Host
A3 A1
B4 B6
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