A Cisco router is stuck in ROMmon mode

TCC_2 · ‎06-22-2009

Core Issue

These are three ways the router can enter ROM Monitor (ROMmon) mode (rommon#>):

Reload, initialize, or power cycle the router with the configuration register boot field set to 0
Reload, initialize, or power cycle the router without having a Cisco IOS Software image to boot from
Press the Break key within the first 60 seconds of the system boot. The break function is enabled during this period

Resolution

For more information on resolving this issue, refer to the Look for a Valid Image in Flash: section of ROMmon Recovery Procedure for the Cisco 7200, 7300, 7400, 7500, RSP7000, Catalyst 5500 RSM, uBR7100, uBR7200, uBR10000, and 12000 Series Routers.

emilio1973 · ‎02-02-2010

Hi, my router is a 2600 and is stuck in a rommon mode. The command "dir flash" shows me this:

rommon 13 > dir flash:
File size Checksum File name
21562452 bytes (0×1490454) 0×17fa c2691-advsecurityk9-mz.124-23.bin (deleted)
rommon14>

When i try to install the new IOs, these are the steps and the result:

Readonly ROMMON initialized
rommon 1 > IP_ADDRESS=192.168.1.1
rommon 2 > IP_SUBNET_MASK=255.255.255.0
rommon 3 > DEFAULT_GATEWAY=192.168.1.1
rommon 4 > TFTP_SERVER=192.168.1.32
rommon 5 > TFTP_FILE=c2691-advsecurityk9-mz.124-23.bin
rommon 6 > set
PS1=rommon ! >
BOOT=
?=0
BSI=0
RANDOM_NUM=955026305
ROM_PERSISTENT_UTC=1014951492
RET_2_RTS=
RET_2_RCALTS=
IP_ADDRESS=192.168.1.1
IP_SUBNET_MASK=255.255.255.0
DEFAULT_GATEWAY=192.168.1.1
TFTP_SERVER=192.168.1.32
TFTP_FILE=c2691-advsecurityk9-mz.124-23.bin
rommon 7 > dnld
~timed out waiting for data – aborting
!rommon 8 >

Someone can help me. I need to load the new IOS or boot the computer with the current

emilio1973 · ‎02-02-2010

if I try to add via xmodem IOS this is what happens:

rommon 1 > xmodem -c c2691-advsecurityk9-mz.124-23.bin
Do not start the sending program yet...
File size Checksum File name
21562452 bytes (0x1490454) 0x17fa c2691-advsecurityk9-mz.124-23.bin (deleted)

WARNING: All existing data in flash will be lost!
Invoke this application only for disaster recovery.
Do you wish to continue? y/n [n]: y
Ready to receive file c2691-advsecurityk9-mz.124-23.bin ...
CCCCCCCCCC
Timeout waiting for data - aborting download...
rommon 2 >

what kind of cable do I need? I'm using a straight connected to f0 / 0?

Thanks

Shajil Melethil · ‎04-09-2013

Hi,

Please check your TFTP server . it might not be started. it shall be started and copy the new IOS to the tftp folder. and do tftpdnld on the router (like above). i had an same issue and i fixed the problem.

Shajil

nasaru123 · ‎03-24-2018

Dear All,

could you please help me resolve this problem..?

I'm using Cisco 819-HG-4G-G-K9 Router, Due to Full disk we try to Format Secondary disk to get some disk space ,but accidentally we choose main flash:0 memmory.. now there is no ios or bootLDR in flash...

i try to connect through xmodem and also tftpdnld ...but no response ...!

the followed steps which i have done to troubleshoot i'm mentioning below.. and please help me to solve this issue..!

1--------------------------------------------------

rommon 8 > sysret

System Return Info:

count: 19, reason: reset

pc:0x0, error address: 0x0

Stack Trace:

FP: 0x00000000, PC: 0x00000000

--------------------------------------------------------------

rommon 11 > context

No context available

rommon 5 > rommon-pref

usage: rommon-pref [readonly|upgrade]

rommon 6 > showmon

Last Reset Reason: System Reset

---------------------------------------------------------------------

rommon 2 > showmon

Last Reset Reason: System Reset

ReadOnly ROMMON version is:

System Bootstrap, Version 15.2(2r)T1, RELEASE SOFTWARE (fc1)

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

No upgrade ROMMON version present

ReadOnly ROMMON currently running

ReadOnly ROMMON is selected for next boot

-----------------------------------------------------------------

rommon 3 > meminfo

-----------------------------------------------------

Current Memory configuration is:

On-board: Size = 1024 MB : Start Phy Addr = 0x0_00000000

-----------------------------------------------------

Main memory size: 1024 MB in 32 bit mode.

Available main memory starts at 0x1008000, size 1032160KB

Smart Init is enabled.

NVRAM size: 256 KB

Manufacturer's JEDEC ID code:

On-board: JDEC ID is not available

------------------------------------------------------------------------------

rommon 25 > set

PS1=rommon ! >

RTC_STAT=0

LICENSE_BOOT_LEVEL=

FE_SPEED_MODE=4

FE_PORT=0

TFTP_RETRY_COUNT=20

WARM_REBOOT=FALSE

RELOAD_TYPE=1

IP_ADDRESS=192.168.10.2

IP_SUBNET_MASK=255.255.255.0

DEFAULT_GATEWAY=192.168.10.1

TFTP_SERVER=192.168.10.45

TFTP_FILE=c800-universalk9-mz.SPA.153-3.M4.bin

FE0_PORT=AUTO

?=0

BSI=0

RANDOM_NUM=1491046230

RET_2_RTS=06:05:53 UTC Sat Mar 17 2018

RET_2_RCALTS=1521266744

rommon 4 > unset bootflash:

unset: "bootflash:" does not exist

rommon 5 > xmodem -c c800-universalk9-mz.SPA.153-3.M4.bin

monitor: command "xmodem" not found

---------------------------------------------------------------------------

rommon 1 > boot flash:

program load complete, entry point: 0x4000000, size: 0x18c40

boot: cannot determine first executable file name ondevice "flash:"

rommon 4 > dir flash:

program load complete, entry point: 0x4000000, size: 0x18c40

Directory of flash:

Kindly please support anyone..

IJAZDAR · ‎08-17-2020

Try and use the tftpdnld -r command where possible as this will load the IOS to RAM and get the device up and working quicker. This command (-r) also prevents any files being deleted on flash i.e. license, backup config, crashinfo, etc or other files you may not be aware of.

Here is a link to ROM Monitor usage (03/03/2008)

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/40sg/configuration/guide/rommon.html

Archive the contents of flash onto your server/laptop and run a format on the flash, this can sometimes help fix read/access issues with flash as well as identify any faults with flash.