Reference Information
•To recover a lost password
•To allow you to manually boot the system using the b command at the bootstrap program prompt
•To force the router to boot automatically from the system bootstrap software (boot image) or from its default system image in onboard Flash memory, and to read any boot system commands that are stored in the configuration file in NVRAM
If the router finds no boot system commands, it uses the configuration register value to form a filename from which to boot a default system image stored on a network server. (See Table 11.)
Table 9 lists the meaning of each of the software configuration memory bits, and Table 10 defines the boot field.
Caution To avoid confusion and possibly halting the router, remember that valid configuration register settings might be combinations of settings and not just the individual settings listed in Table 9. For example, the factory default value of 0x0102 is a combination of settings.
Table 9 | Software Configuration Register Bit Meanings | ||
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Bit Number1 | Hexadecimal | Meaning | |
00 to 0F |
| 0x0000 to 0x000F | Boot field (see Table 10) |
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06 |
| 0x0040 | Causes system software to ignore NVRAM contents |
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07 |
| 0x0080 | OEM2 bit enabled |
08 |
| 0x0100 | Break disabled |
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09 |
| 0x0200 | Use secondary bootstrap |
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10 |
| 0x0400 | IP broadcast with all zeros |
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11 to 12 |
| 0x0800 to 0x1000 | Console line speed (default is 9600 baud) |
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13 |
| 0x2000 | Boot default Flash memory software if network boot fails |
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14 |
| 0x4000 | IP broadcasts do not have network numbers |
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15 |
| 0x8000 | Enable diagnostic messages and ignore NVRAM contents |
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1.The factory default value for the configuration register is 0x0102. This value is a combination of the following: bit 8 = 0x0100 and bits 00 through 03 = 0x0001 (see Table 11).
2.OEM = original equipment manufacturer
Table 10 Explanation of Boot Field (Software Configuration Register Bits 00 to 0F)
Boot Field | Meaning |
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00 | Stays at the system bootstrap prompt |
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01 | Boots the first system image in onboard Flash memory |
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02 to 0F | Specifies a default network boot filename |
| Enables boot system commands that override the default network boot filename |
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Route Switch Processor (RSP8) Installation and Configuration Guide
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