HP StorageWorks 500 G2 Modular Smart Array - Manual (Page 53)

Hardware options installation 53
4. Install the 4-Port Shared Storage Module.
MSA500 G2 Controller option
The HP StorageWorks Modular Smart Array 500 Generation 2 storage system
ships with one HP StorageWorks Modular Smart Array 500 Generation 2
controller. To provide redundancy and maximize uptime, install a second
MSA500 G2 controller.
Controller installation requirements
Observe the following guidelines:
• If a controller has more than one cache DIMM, be sure that both DIMMs
have the same memory capacity.
• Always upgrade the cache in both controllers in a storage system with
redundant controllers.
• In a storage system with a redundant controller, be sure that both controllers
have the same number of DIMMs and that all DIMMs have the same
memory capacity.