새로 들어온 Network Device 의 IOS Upgrade를 하던 중 이미지도 정상적으로 Upload 되고 boot system 도 정상적으로 지정이 되었는데 Reload 를 하면 이전 이미지로 booting 이 되는 난감한 상황 속에서 원인을 찾았네요. 정상적으로 사용되는 config-register 의 값은 0x2102 인데 0x2 로 지정되어 있더군요.
config-register 값은 보통 show version 시 마지막 줄에서 확인 할 수 있어요.
ex )
R1>sh ver
Cisco Internetwork Operating System Software
IOS (tm) 2600 Software (C2691-IS-M), Version 12.3(22), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by cisco Systems, Inc.
Compiled Wed 24-Jan-07 17:17 by ccai
Image text-base: 0x60008AF4, data-base: 0x61C6A000ROM: ROMMON Emulation Microcode
ROM: 2600 Software (C2691-IS-M), Version 12.3(22), RELEASE SOFTWARE (fc2)R1 uptime is 1 minute
System returned to ROM by unknown reload cause - suspect boot_data[BOOT_COUNT] 0x0, BOOT_COUNT 0, BOOTDATA 19
System image file is "tftp://255.255.255.255/unknown"cisco 2691 (R7000) processor (revision 0.1) with 120832K/10240K bytes of memory.
Processor board ID XXXXXXXXXXX
R7000 CPU at 80MHz, Implementation 39, Rev 2.1, 256KB L2, 512KB L3 Cache
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
2 FastEthernet/IEEE 802.3 interface(s)
4 Serial network interface(s)
DRAM configuration is 64 bits wide with parity enabled.
55K bytes of non-volatile configuration memory.
65536K bytes of ATA System CompactFlash (Read/Write)Configuration register is 0x2102
Configuration register 값에 대한 정리.
Software Configuration Bit Meanings
| Bit No. | Hex | Meaning |
|---|---|---|
| 00-03 | 0x0000-0x000F | Boot Field |
| 06 | 0x0040 | Ignore NVM contents |
| 07 | 0x0080 | OEM bit enabled |
| 08 | 0x0100 | Break disabled |
| 10 | 0x0400 | IP broadcast with all zeros |
| 11-12 | 0x0800-0x1000 | Console line speed |
| 13 | 0x2000 | Boot default ROM software if network boot fails |
| 14 | 0x4000 | IP broadcasts do not have net numbers |
| 15 | 0x8000 | Enable diagnostic messages and ignore NVM contents |
Explanation of Boot Field (Configuration Register Bits 00-03)
| Boot Field | Meaning |
|---|---|
| 00 | Stays at the system bootstrap prompt |
| 01 | Boots system image on EPROM |
| 02-F | Specifies a default netboot filename
Enables boot system commands that override default netboot filename |
Default Boot Filenames
| Action/Filename | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
|---|---|---|---|---|
| Bootstrap monitor | 0 | 0 | 0 | 0 |
| ROM software | 0 | 0 | 0 | 1 |
| cisco2-igs | 0 | 0 | 1 | 0 |
| cisco3-igs | 0 | 0 | 1 | 1 |
| cisco4-igs | 0 | 1 | 0 | 0 |
| cisco5-igs | 0 | 1 | 0 | 1 |
| cisco6-igs | 0 | 1 | 1 | 0 |
| cisco7-igs | 0 | 1 | 1 | 1 |
| cisco10-igs | 1 | 0 | 0 | 0 |
| cisco11-igs | 1 | 0 | 0 | 1 |
| cisco12-igs | 1 | 0 | 1 | 0 |
| cisco13-igs | 1 | 0 | 1 | 1 |
| cisco14-igs | 1 | 1 | 0 | 0 |
| cisco15-igs | 1 | 1 | 0 | 1 |
| cisco16-igs | 1 | 1 | 1 | 0 |
| cisco17-igs | 1 | 1 | 1 | 1 |
Configuration Register Settings for Broadcast Address Destination
| Bit 14 | Bit 10 | Address (<net> <host>) |
|---|---|---|
| off | off | <ones> <ones> |
| off | on | <zeros> <zeros> |
| on | on | <net> <zeros> |
| on | off | <net> <ones> |
System Console Terminal Baud Rate Settings
| Baud | Bit 12 | Bit 11 |
|---|---|---|
| 9600 | 0 | 0 |
| 4800 | 0 | 1 |
| 1200 | 1 | 0 |
| 2400 | 1 | 1 |
원문링크
invalid-file