Cisco Systems 12810 Router User Manual


 
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Cisco 12010, Cisco 12410, and Cisco 12810 Router Installation and Configuration Guide
OL-11496-01
Chapter 4 System Startup and Basic System Configuration
Configuring the Software Configuration Register
The boot field (Table 4-5) defines a source for booting a default Cisco IOS
software image required to run the router. The content of the boot field is specified
as a binary number.
Note A Cisco 12010, Cisco 12410, or Cisco 12810 router is shipped with a boot image
in the boot flash, and a Cisco IOS image on a flash memory card.
Setting Software Configuration Settings
The four low-order bits of the software configuration register (bits 3, 2, 1, and 0)
form a boot field that defines the source of a Cisco IOS software image for booting
the router.
You can set or change the contents of the boot field by entering the
config-register command at the global configuration mode prompt
[
Milo(config)#].
Note The factory default configuration register setting for an RP is 0x0102.
Table 4-5 Boot Field—Software Configuration Register
Boot Field Meaning at Power-On
00 The system remains at the ROM monitor prompt (
rommon>),
awaiting a user command to boot the system manually.
01 The system automatically boots the first system image found in
the onboard flash memory SIMM on the RP.
02 to 0F The system boots automatically from a default Cisco IOS
software image stored on a TFTP server in the network. This boot
field setting requires that the Ethernet port on the RP is
configured and operational. This setting also enables boot system
commands that override the default filename.