So far we have been talking about the performance of the storage infrastructure. The main factor that affects the overall performance is the device type that we use within the storage array.

Before we move on to looking at the actual device types, we need to understand the different physical ports on the devices:

• SATA: These devices have a single port. They cannot be connected to both service processors simultaneously.
• SAS: The device has two ports and can be connected to two service processors simultaneously. SAS devices are usually faster.