Sun Microsystems Sun Fire V490 - Manual (Page 110)

82 Sun Fire V490 Server Administration Guide • August 2004
The dashed lines in FIGURE 6-3 represent boundaries between FRUs. Suppose a POST
diagnostic is running in the processor in the left part of the diagram. This diagnostic
attempts to initiate a built-in self-test in a PCI device located in the right side of the
diagram.
If this built-in self-test fails, there could be a fault in the PCI controller, or, less likely,
in one of the data paths or components leading to that PCI controller. The POST
diagnostic can tell you only that the test failed, but not why. So, though the POST
may present very precise data about the nature of the test failure, any of three
different FRUs could be implicated.
Controlling POST Diagnostics
You control POST diagnostics (and other aspects of the boot process) by setting
OpenBoot configuration variables in the IDPROM. Changes to OpenBoot
configuration variables generally take effect only after the machine is restarted.
These variables affect OpenBoot Diagnostics tests as well as POST diagnostics.
TABLE 6-2 lists the most important and useful of these variables. You can find more
extensive lists and descriptions in OpenBoot PROM Enhancements for Diagnostic
Operation and OpenBoot 4.x Command Reference Manual. The former is included on the
Sun Fire V490 Documentation CD. The latter is included with the Solaris Software
Supplement CD that ships with Solaris software.
You can find instructions for changing OpenBoot configuration variables in “How to
View and Set OpenBoot Configuration Variables” on page 180.
TABLE 6-2 OpenBoot Configuration Variables
OpenBoot Configuration
Variable
Description and Keywords
auto-boot Determines whether the operating system automatically starts up. Default is true.
• true—Operating system automatically starts once firmware tests finish.
• false—System remains at ok prompt until you type boot.
auto-boot-on-
error?
Determines whether the system attempts to boot after a nonfatal error. Default is
true
.
• true — System automatically boots after a nonfatal error if the variable
auto-boot? is also set to true.
• false — System remains at the ok prompt.
diag-level Determines the level or type of diagnostics executed. Default is max.
• off—No testing.
• min—Only basic tests are run.
• max—More extensive tests may be run, depending on the device.