877 rommon problem

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lgijssel Wed, 07/23/2008 - 02:16
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Might be a buggy IOS that has a memory leak.

The router will reload when all memory is gone.

Also, you should check that the config register is set up to boot the first file from flash.

To give more precise directions, you should post your config and the output of "sh ver".



Thanks Leo sh ver is as follows -

Cisco IOS Software, C870 Software (C870-ADVIPSERVICESK9-M), Version 12.4(9)T4, RELEASE SOFTWARE (fc2)

Technical Support: http://www.cisco.com/techsupport

Copyright (c) 1986-2007 by Cisco Systems, Inc.

Compiled Thu 07-Jun-07 14:00 by prod_rel_team

ROM: System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE

NCCSUF01 uptime is 2 hours, 13 minutes

System returned to ROM by power-on

System image file is "flash:c870.bin"

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[email protected].

Cisco 877 (MPC8272) processor (revision 0x300) with 118784K/12288K bytes of memory.

Processor board ID FCZ1222137R

MPC8272 CPU Rev: Part Number 0xC, Mask Number 0x10

4 FastEthernet interfaces

1 ATM interface

128K bytes of non-volatile configuration memory.

24576K bytes of processor board System flash (Intel Strataflash)

Configuration register is 0x1

francisco_1 Wed, 07/23/2008 - 02:30
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logon to the router and change the Configuration register to 0x2102 and reload.

francisco_1 Wed, 07/23/2008 - 02:47
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Config register

The NVRAM has a special location that contains the 16-bit configuration register. Every time the router boots it reads this value. The config-register value is a hexadecimal value ranging from from 0x0000 to 0xFFFF and can be set byusing the config-register command. The most important portion of the configuration register to understand is the boot field (bit 0 through 3, hexadecimal range 0x0000-0x000F). The boot field value is used to specify from which location the IOS image should be loaded or bypassed even during startup.

Boot field Meaning

0x0 The router will enter ROM monitor mode and remain at the system bootstrap prompt.

0x1 The IOS image stored in ROM will be loaded.

0x2-0xF The router will boot as normal and load the default IOS image stored in Flash and enables boot system commands.

please rate is this helps.

lgijssel Wed, 07/23/2008 - 02:40
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Your IOS seems to be not too recent so it might contain a bug. My advice would be to get an update.

Changing the config-reg to 0x2102 will at least make the router reboot instead of entering rommon.



francisco_1 Wed, 07/23/2008 - 03:17
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Cisco engineering has identified some serious software issue with the release 12.4(9)T4 (ADVANCED IP SERVICES) which might be related to the router reload and config-register changes. Suggest you upgrade to at least 12.4.15T5.

francisco_1 Wed, 07/23/2008 - 03:56
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do you need help with anything else? if not can you please rate the discussion.




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