Compaq AlphaServer DS20, Руководство по обслуживанию

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Halts, Console Commands, and Environment Variables A-5
by the RCM reset command to force a halt assertion. Upon reset, the system powers
up to the SRM console, but the SRM console does not load the AlphaBIOS console.
Clearing a Halt Assertion
Clear a halt assertion as follows:
•
If the halt assertion was caused by pressing the Halt button or remotely entering
the RCM halt command, the console uses the halt assertion once, then clears it.
•
If the halt assertion was caused by entering the RCM haltin command, enter the
RCM haltout command or cycle power on the local system.
Disabling Autoboot
The system automatically boots the selected operating system at power-up or reset if
the following environment variables are set:
•
For Compaq Tru64 UNIX and OpenVMS, the SRM environment variables
os_type, auto_action, bootdef_dev, boot_file, and boot_osflags
•
For Windows NT, the SRM os_type environment variable and the Auto Start
selection in the AlphaBIOS Standard CMOS Setup screen
You might want to prevent the system from autobooting so you can perform tasks
from the SRM console. Use one of the methods described previously to force a halt
assertion. When the SRM console prompt is displayed, you can enter commands to
configure or test the system. Chapter 4 of your system User’s Guide describes the
SRM console commands and environment variables.
Disabling the SRM Power-Up Script
The system has a power-up script (file) named “nvram” that runs every time the
system powers up. If you accidentally insert a command in the script that will cause a
system problem, disable the script by using one of the methods described previously to
force a halt assertion. When the SRM console prompt is displayed, edit the script to
delete the offending command. See Section 4.4 of your system User’s Guide for more
information on editing the nvram script.