IBM DS8000 manual Designed for scalability, Scalability for capacity, Large and scalable capacity

Table 6-1 DS8000 model comparison

Base Mod	Images	Exp Mod	Proc type	DDMs	Proc Mem	HAs
921	1	None	2-way	<= 128	<= 128 GB	<= 16
			1.5 GHz
		1 x 92E		<= 384
922	1	None	4-way	<= 128	<= 256 GB	<= 16
			1.9 GHz
		1 x 92E		<= 384		<= 32
		2 x 92E		<= 640
9A2	2	None		<= 128		<= 16
		1 x 9AE		<= 384		<= 32
		2 x 9AE		<= 640

Depending on the DDM sizes, which can be different within a 921, 922, or 9A2, and the number of DDMs, the total capacity is calculated accordingly.

Each FCP/FICON adapter has four Fibre Channel ports, which provide up to 128 Fibre Channel ports. Each ESCON adapter has two ports, therefore, the maximum number of ports is 64.

6.3 Designed for scalability

One of the advantages of the DS8000 series is its linear scalability for capacity and performance. If your business (or your customer’s business) grows rapidly, you may need much more storage capacity, faster storage performance, or both. The DS8000 series can meet these demands within a single storage unit. We explain the scalability in this section.

6.3.1 Scalability for capacity

The DS8000 series has a linear capacity growth up to 192 TB and can add additional DDMs without a system disruption. IBM plans to offer larger models in the future.

Large and scalable capacity

You can have from 16 DDMs up to 384 DDMs (Model 921) or 640 DDMs (Model 922 or 9A2) in a DS8000.

￿Each base frame can have up to 128 DDMs and an expansion frame can have up to 256 DDMs.

￿The DS8100 can have one expansion frame and the DS8300 can have two expansion frames

￿The DS8000 can contain three types of DDMs, 73 GB (15,000 RPM), 146 GB (10,000 RPM), and 300 GB (10,000 RPM).

Therefore, you can select a physical capacity from 1.1 TB (73 GB x 16 DDMs) up to 192 TB (300 GB x 640 DDMs).

We summarize these characteristics in Table 6-2 on page 110.

Chapter 6. IBM TotalStorage DS8000 model overview and scalability 109