IBM DS6000 Series manual DS6800 capacity upgrade, DS6800 physical capacity examples

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 5-1describes the capacity of the DS6800 with expansion enclosures.

Table 5-1 DS6800 physical capacity examples

Model	with 73 GB DDMs	with 146 GB DDMs	with 300 GB DDMs
1750-511	1.17 TB	2.34 TB	4.80 TB
(16 DDMs)
1750-511 + 6 Exp	8.18 TB	16.35 TB	33.60 TB
(112 DDMs)

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 5-5is an example of how to connect an expansion enclosure to each group alternately.

Chapter 5. IBM TotalStorage DS6000 model overview 87