• For 2078-92F, 2078-A9F 5U expansion enclosures, the blue pull tab must be above the connector (
2
• Insert the connector gently until it clicks into place. If you feel resistance, the connector is probably
oriented the wrong way. Do not force it.
• When inserted correctly, the connector can be removed only by pulling the tab.
Be aware of the following guidelines when you attach the cables to the SAS ports.
• No cable can be connected between a port on a left canister and a port on a right canister of the
expansion enclosures.
• Ensure that cables are installed in an orderly way to reduce the risk of cable damage when replaceable
units are removed or inserted.
• SAS cables must be routed through the cable management arms to reduce the risk of disconnecting the
nodes from their storage arrays. This step also helps to protect the SAS cables from getting damaged if
you slide the node or enclosure out of the rack while they are attached. Arrange your cables to provide
access to the following components:
– Ethernet ports, including the technician port. The technician port is used for initial setup of the
system by directly attaching to a personal computer. It can also be used to complete service actions
for the system.
– USB ports.
– Fibre Channel ports. If your system has an optionally installed Fibre Channel adapter for host and
external storage attachment, ensure that these ports are accessible.
– The nodes and the enclosures themselves. Access is required to the hardware for servicing and for
safely removing and replacing components by using two or more people.
Procedure
1. Install the cables, as shown in Figure 59 on page 58.
Note: Figure 59 on page 58 shows the cable connections between the SAS enclosures and the
control enclosure. It does not imply or represent the precise racking order for the enclosures in a rack.
However, due to its size and weight, always place the 2078-92F, 2078-A9F enclosure near the bottom
of the rack.
Figure 59. Connecting the SAS cables
2. If more I/O groups are configured, repeat the cabling procedure for the other I/O groups. Each system
can have a maximum of four I/O groups, with two chains of expansion enclosures attached to each I/O
group. Two chains of expansion enclosures can be attached to each I/O group. On each SAS chain, the
systems can support up to a SAS chain weight of 10.
Combining 2U and 5U expansion enclosures
About this task
You can combine 2U and 5U expansion enclosures in a SAS chain. The limiting factor is the combined
chain weight of the various components. The maximum SAS chain weight that can be attached to a node
SAS port is 10:
• 2078-92F, 2078-A9F enclosures have a chain weight of 2.5
• 2077-24F and 2077/2078-12F enclosures have a chain weight of 1.
Example
Table 11 on page 59 shows example of different combinations of SAS weights.
58 Storwize V5100 : Quick Installation Guide for MTM 2078-424, 2078-12F, 2078-24F, 2078-92F, and 2078-
U5B
Summary of Contents for Storwize V5100 MTM 2078-12F
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