IBM TotalStorage DS6000 Series - Manual (Page 111)

Chapter 5. IBM TotalStorage DS6000 model overview 87
The DS6800 server enclosure can have from 8 up to 16 DDMs and can connect 7 expansion
enclosures. Each expansion enclosure also can have 16 DDMs. Therefore, in total a DS6800
storage unit can have 16 + 16 x 7 = 128 DDMs.
You can select from four types of DDMs:
73 GB 15k RPM
146 GB 10k RPM
146 GB 15k RPM
300 GB 10k RPM
Therefore, a DS6800 can have from 584 GB (73 GB x 4 DDMs) up to 38.4TB (300 GB x 128
DDMs).
Table 5-1 describes the capacity of the DS6800 with expansion enclosures.
Table 5-1 DS6800 physical capacity examples
In addition, the DS6800 and expansion enclosures can have different types of DDMs in each
enclosure (an intermix configuration).
The DS6800 capacity upgrade
The DS6800 has two enclosure groups for attaching expansion enclosures. One group can
have a server enclosure and up to three expansion enclosures (we call this group
Loop 0
)
and the other group can have up to four expansion enclosures (we call this group
Loop 1
).
You can attach additional expansion enclosures to the two groups for well-balanced capacity.
Figure 5-5 on page 88 illustrates the connectivity of the server and expansion enclosures.
Each DS6800 controller has four FC-AL ports and two of them connect to the dual redundant
loops of the first group (Loop 0), and the others to the second group (Loop 1). The FC-AL port
in Loop 0 is called the
disk exp
port, and the port in the Loop 1 is called the
disk control
port.
These groups are independent and there is no restriction on the connection sequence of
expansion enclosures. Figure 5-5 is an example of how to connect an expansion enclosure to
each group alternately.
Model with 73 GB DDMs with 146 GB DDMs with 300 GB DDMs
1750-511
(16 DDMs) 1.17 TB 2.34 TB 4.80 TB
1750-511 + 6 Exp
(112 DDMs) 8.18 TB 16.35 TB 33.60 TB