Cisco WS-SUP32-GE-3B Software Configuration Guide - Page 71

Chapter 3 Configuring the Switch for the First Time Modifying the Supervisor Engine Startup Configuration CONFIG_FILE Environment Variable For class A flash file systems, the CONFIG_FILE environment variable specifies the file system and filename of the configuration file to use for initialization (startup). Valid file systems can include nvram:, disk0:, and sup-bootflash:. For detailed file management configuration information, refer to the Cisco IOS Configuration Fundamentals Configuration Guide at this URL: http://www.cisco.com/en/US/docs/ios/12_2/configfun/configuration/guide/ffun_c.html After you save the CONFIG_FILE environment variable to your startup configuration, the switch checks the variable upon startup to determine the location and filename of the configuration file to use for initialization. The switch uses the NVRAM configuration during initialization when the CONFIG_FILE environment variable does not exist or when it is null (such as at first-time startup). If the switch detects a problem with NVRAM or a checksum error, the switch enters setup mode. See the "Using the Setup Facility or the setup Command" section on page 3-2 for more information on the setup command facility. Controlling Environment Variables Although the ROM monitor controls environment variables, you can create, modify, or view them with certain commands. To create or modify the BOOT, BOOTLDR, and CONFIG_FILE environment variables, use the boot system, boot bootldr, and boot config global configuration commands. Refer to the "Specify the Startup System Image in the Configuration File" section in the "Loading and Maintaining System Images and Microcode" chapter of the Configuration Fundamentals Configuration Guide for details on setting the BOOT environment variable. Refer to the "Specify the Startup Configuration File" section in the "Modifying, Downloading, and Maintaining Configuration Files" chapter of the Configuration Fundamentals Configuration Guide for details on setting the CONFIG_FILE variable. Note • When you use the boot system, boot bootldr, and boot config global configuration commands, you affect only the running configuration. You must save the environment variable settings to your startup configuration to place the information under ROM monitor control and for the environment variables to function as expected. Enter the copy system:running-config nvram:startup-config command to save the environment variables from your running configuration to your startup configuration. • Cisco IOS software supports the boot bootldr global configuration command and the ROM monitor supports the BOOTLDR environment variable, but because Release 12.2ZY does not require use of a bootloader image, there are no Release 12.2ZY bootloader images. You can view the contents of the BOOT, BOOTLDR, and the CONFIG_FILE environment variables using the show bootvar command. This command displays the settings for these variables as they exist in the startup configuration as well as in the running configuration if a running configuration setting differs from a startup configuration setting. This example shows how to check the BOOT, BOOTLDR, and the CONFIG_FILE environment variables: Router# show bootvar BOOT variable = disk0:c6sup22-jsv-mz.121-5c.EX.bin,1; OL-11439-03 Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY 3-25