Cisco Catalyst 3750 Software Configuration Manual page 78

Modifying the Startup Configuration
Table 3-4
Table 3-4 Environment Variables
Variable Boot Loader Command
BOOT set BOOT filesystem:/file-url ...
A semicolon-separated list of executable files to
try to load and execute when automatically
booting. If the BOOT environment variable is not
set, the system attempts to load and execute the
first executable image it can find by using a
recursive, depth-first search through the flash file
system. If the BOOT variable is set but the
specified images cannot be loaded, the system
attempts to boot the first bootable file that it can
find in the flash file system.
MANUAL_BOOT set MANUAL_BOOT yes
Determines whether the switch automatically or
manually boots.
Valid values are 1, yes, 0, and no. If it is set to no
or 0, the boot loader attempts to automatically
boot the system. If it is set to anything else, you
must manually boot the switch from the boot
loader mode.
CONFIG_BUFSIZE set CONFIG_BUFSIZE size
Changes the buffer size that IOS uses to hold a
copy of the configuration file in memory. The
configuration file cannot be larger than the buffer
size allocation. The range is from 4096 to 524288
bytes.
CONFIG_FILE set CONFIG_FILE flash:/file-url
Changes the filename that IOS uses to read and
write a nonvolatile copy of the system
configuration.
Catalyst 3750 Metro Switch Software Configuration Guide
3-14
describes the function of the most common environment variables.
Chapter 3 Assigning the Switch IP Address and Default Gateway
IOS Global Configuration Command
boot system filesystem:/file-url
Specifies the IOS image to load during the next
boot cycle. This command changes the setting of
the BOOT environment variable.
boot manual
Enables manually booting the switch during the
next boot cycle and changes the setting of the
MANUAL_BOOT environment variable.
The next time you reboot the system, the switch is
in boot loader mode. To boot the system, use the
boot loader boot flash:filesystem:/file-url
command, and specify the name of the bootable
image.
boot buffersize size
Specifies the size of the file system-simulated
NVRAM in flash memory. The buffer holds a
copy of the configuration file in memory. This
command changes the setting of the
CONFIG_BUFSIZE environment variable.
You must reload the switch by using the reload
privileged EXEC command for this command to
take effect.
boot config-file flash:/file-url
Specifies the filename that IOS uses to read and
write a nonvolatile copy of the system
configuration. This command changes the
CONFIG_FILE environment variable.
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