IBM OpenPower 720, Технический обзор и введение

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OpenPower 720 Technical Overview and Introduction
reaches the SMS menus, all of the necessary tests have been performed and the machine is
scanning the bus for a boot source.
Most system backplanes are designed such that the drive in the first slot spins up
immediately after power-on, and other drives will wait for the operating system to send a
command before spinning up. Disk drive bays 1 and 5 are hardwired to spin-up immediately.
The left-most and accordingly bottom-most slot of the 4-pack disk backplanes (SCSI ID 8,
boot, autostart) is set to spin up immediately after power-on. The power-on delay sequence is
performed to prevent power supply overloading. This behavior makes the disk in the first slot
of the first 4-pack DASD backplane the preferred boot device. See Figure 2-15 to locate all of
the disk bays.
Figure 2-15 Disk bays and SCSI addresses within a OpenPower 720
When SMS menus are available, the Select Boot Options menu can be used to view and set
various options regarding the installation devices and boot devices:
1. Select Install or Boot a Device
Enables you to select a device to boot from or install the operating system from. This
selection is for the current boot only.
2. Select Boot Devices
Enables you to set the boot list.
3. Multiboot Startup
Toggles the multiboot startup flag, which controls whether the multiboot menu is invoked
automatically on startup.
2.11.9 Additional boot options
Instead of booting from the preferred boot device, or from any other internal disks, there are a
number of other possibilities:
DVD-ROM, DVD-RAM These devices can be used to boot the system, or a
logical partition (if the resource is available to the specific
partition), so that a system can be loaded, system