IBM DS8000 manual External S-HMC, S-HMC and Ethernet switches

as shown. To interconnect two DS8000 base frames, FC1190 would provide a pair of 31m Ethernet cables to connect from port 16 of each switch in the second base frame into port 15 of the first frame. If the second S-HMC is installed in the second DS8000, it would remain plugged into port 1 of its Ethernet switches.

S-HMC and a pair of Ethernet switches
S-HMC	Ethernet ports for private
	S-HMC network
SFI-1	SFI-2
	Port for
	Customer
	Network
SFI--11 SFI-2
Ports for S-HMC #2	Pair of Ethernet switches
- Storage Facility Image (SFI)

Figure 9-1 S-HMC and Ethernet switches

9.2.1 External S-HMC

Additionally, the DS8000 can have an external S-HMC (feature code 1110), which may be ordered today in preparation for its availability later in 2005 when this will be a supported configuration. The external S-HMC is equivalent hardware to the internal S-HMC and needs to be installed in a customer-supplied 19-inch IBM or a non-IBM rack (1U server/1U display). Configuration management is achieved either in real-time or offline configuration mode.

In environments with high availability requirements and Advanced Copy Services, it is recommended that an external S-HMC is installed to eliminate single points of failure. Since the S-HMC is the only service personnel interface available, an external S-HMC will greatly enhance maintenance operational capabilities as a result of internal S-HMC failures. The external S-HMC is an optional priced feature. To help preserve console functionality, the external and the internal S-HMCs are not available to be used as a general purpose computing resource.

Tip: To ensure that IBM service representatives can quickly and easily access an external S-HMC, place the external S-HMC rack within 15.2 m (50 ft.) of the storage units connected to it.

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