Sun Microsystems Sun Fire V490 - Manual (Page 81)

Chapter 4 Network Interfaces and System Firmware 53
Note – Using the Stop-A keyboard command to enter the OpenBoot environment
during power-on or reset will immediately disable the OpenBoot environmental
monitor. If you want the OpenBoot PROM environmental monitor enabled, you
must reenable it prior to rebooting the system. If you enter the OpenBoot
environment through any other means—by halting the operating system, by power-
cycling the system, or as a result of a system panic—the OpenBoot environmental
monitor will remain enabled.
Automatic System Shutdown
If the OpenBoot environmental monitor detects a critical overtemperature condition,
it will initiate an automatic system power off sequence. In this case, a warning
similar to the following is generated to the system console:
If necessary, you can type Ctrl-C to abort the automatic shutdown and return to the
system ok prompt; otherwise, after the 30 seconds expire, the system will power off
automatically.
Note – Typing Ctrl-C to abort an impending shutdown also has the effect of
disabling the OpenBoot environmental monitor. This gives you enough time to
replace the component responsible for the critical condition without triggering
another automatic shutdown sequence. After replacing the faulty component, you
must type the env-on command to reinstate OpenBoot environmental monitoring.
Caution – If you type Ctrl-C to abort an impending shutdown, you should
immediately replace the component responsible for the critical condition. If a
replacement part is not immediately available, power off the system to avoid
damaging system hardware.
OpenBoot Environmental Status Information
The OpenBoot command .env enables you to obtain status on the current state of
everything of interest to the OpenBoot environmental monitor. This includes
information about the system’s power supplies, fans, and temperature sensors.
WARNING: SYSTEM POWERING DOWN IN 30 SECONDS!
Press Ctrl-C to cancel shutdown sequence and return to ok prompt.