Rommon mode - Router 3945

[dyl33]

Hi, my router is currently stuck in rommon mode.

Are there any helpful commands out there that will help me understand why my router is stuck in rommon mode?

Is there anything I can test/try to get out of rommon mode?

If need more information please reply, thank you.

[Leo Laohoo]

Console into the router and reboot the router.  Post the complete boot-up process. 

Please provide the complete output to the following commands in ROMMON: 

1. set

2. dir flash:

[dyl33]

Hi, I was trying different things out last night to resolve it.

But I think I have it stuck in a boot loop.

It now keeps spuing out this message:

IOS Image Load Test
___________________
Digitally Signed Release Software
program load complete, entry point: 0x4000000, size: 0x5a5f540
Self decompressing the image : ###################################################################### ##################################################################################################### ##################################################################################################### ##################################################################################################### ##################################################################################################### ##################################################################################################### ##################################################################################################### ##################################################################################################### ############################################# [OK]

*** Machine Check Exception ***
CPU context of the most recent exception:
R0 = 0x38800001 R1 = 0x3ffffde0 R2 = 0xc9f3f775 R3 = 0x00000000
R4 = 0x989e0f9d R5 = 0x00000000 R6 = 0x10000000 R7 = 0x0000758c
R8 = 0x10000000 R9 = 0x128fd3c4 R10 = 0x989e0f9d R11 = 0x1d4ad358
R12 = 0x3ffff704 R13 = 0x03febfb9 R14 = 0x10005848 R15 = 0x00000000
R16 = 0x00000006 R17 = 0x100003b4 R18 = 0x1001dccc R19 = 0x00000006
R20 = 0x00008000 R21 = 0x0d47f58c R22 = 0x10006e28 R23 = 0x0c00029c
R24 = 0x05a56e2c R25 = 0x10001000 R26 = 0x10001014 R27 = 0x0134ade0
R28 = 0x1002ddcc R29 = 0x3a5a09d4 R30 = 0x96ad5391 R31 = 0x10000000
CR = 0x22000042 LR = 0x040009d0 CTR = 0x02aebfe6 XER = 0x20000000
TBU = 0x00000001 TBL = 0xaa164636 DEAR = 0x00000000 IVPR = 0x00000000
PVR = 0x00000000 DBCR0 = 0x00000000 DBCR1 = 0x00000000 DBCR2 = 0x00000000
IAC1 = 0x00000000 IAC2 = 0x00000000 DAC1 = 0x00000000 DAC2 = 0x00000000
CSRR0 = 0x00000000 CSRR1 = 0x00000000 MCSRR0 = 0x04000a20 MCSRR1 = 0x02009200
PC = 0x04000a20 MSR = 0x02009200

CPU SPR Registers:
CSRR0 = 0x00000000
CSRR1 = 0x00000000
CTR = 0x02aebfe6
DAC1 = 0x00000000
DAC2 = 0x00000000
DBCR0 = 0x00000000
DBCR1 = 0x00000000
DBCR2 = 0x00000000
DBSR = 0x20000000
DEAR = 0x00000000
DEC = 0x00011e94
ESR = 0x00000000
IAC1 = 0x00000000
IAC2 = 0x00000000
IVOR0 = 0x00000100
IVOR1 = 0x00000200
IVOR2 = 0x00000300
IVOR3 = 0x00000400
IVOR4 = 0x00000500
IVOR5 = 0x00000600
IVOR6 = 0x00000700
IVOR8 = 0x00000c00
IVOR10 = 0x00000900
IVOR11 = 0x00000b00
IVOR12 = 0x00000d00
IVOR13 = 0x00001400
IVOR14 = 0x00001300
IVOR15 = 0x00001500
IVPR = 0xff800000
LR = 0xff83f1d8
PIR = 0x00000000
PVR = 0x80210030
SPRG0 = 0x45e054ca
SPRG1 = 0x45e054ca
SPRG2 = 0x989e0f9d
SPRG3 = 0x00000000
SPRG4 = 0x040009d0
SPRG5 = 0x00000000
SPRG6 = 0x00000000
SPRG7 = 0x00000000
SRRO = 0x04000a0c
SRR1 = 0x02009200
TBL = 0xb328de9e
TBU = 0x00000001
TCR = 0x04400000
TSR = 0x08000000
USPRG0 = 0x00000000
XER = 0x20000000
BBEAR = 0x00000000
BBTAR = 0x00000000
BUCSR = 0x00000001
HID0 = 0x00004080
HID1 = 0xc5021000
IVOR32 = 0x00000f00
IVOR33 = 0x00001000
IVOR34 = 0x00001100
IVOR35 = 0x00001200
L1CFG0 = 0x00383820
L1CFG1 = 0x00383820
L1CSR0 = 0x00010001
L1CSR1 = 0x00000001
MAS0 = 0x10000000
MAS1 = 0xc0000700
MAS2 = 0xff000002
MAS3 = 0xff000033
MAS4 = 0x00000000
MAS6 = 0x00000000
MCAR = 0x128fd3c0
MCSR = 0x00000008
MCSRR0 = 0x04000a20
MCSRR1 = 0x02009200
MMUCFG = 0x000019c4
MMUCSR0 = 0x00000000
PID0 = 0x00000000
PID1 = 0x00000000
PID2 = 0x00000000
SPEFSCR = 0x00000000
SVR = 0x80e80021
TLB0CFG = 0x04110200
TLB1CFG = 0x101bc010
System Return Info:
count: 19, reason: reset
pc:0x0, error address: 0x0
Stack Trace:
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000
FP: 0x00000000, PC: 0x00000000

System Bootstrap, Version 15.0(1r)M8, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2010 by cisco Systems, Inc.

Total memory size = 1024 MB - DIMM0 = 512 MB, DIMM1 = 512 MB
CISCO3945-CHASSIS with C3900-SPE150/K9 with 1048576 Kbytes of main memory
Main memory is configured to 72/72(dimm 0/1) bit mode with ECC enabled

Readonly ROMMON initialized
program load complete, entry point: 0x4000000, size: 0x18fa0
program load complete, entry point: 0x4000000, size: 0x18fa0

[Leo Laohoo]

1. Power down the router and remove the power cable (to minimize chances of self-inflicted electrocution). 
2. Pop the lid of the router. 
3. Make sure to wear a non-static ground strip.  
4. Locate where the DRAM is and gently remove it.  
5. Use a non-static cloth and wipe the contacts clean. 
6. Put the DRAM back. 
7. Power up the router.

[johnlloyd_13]

hi,

try to remove/eject the compact flash card (CF) to force it to ROMMON.

see link below. instruction is the same for 2900 and 3900 ISR.

https://www.cisco.com/c/en/us/td/docs/routers/access/2900/hardware/installation/guide/Hardware_Installation_Guide/Internal_Modules.html#20935

if this still doesn't work then it's time to replace the hardware. note 3900 had already reached EOL.

[dyl33 · Accepted solution]

Hi, Guys thank you for your help, I forgot to mention I replaced the hardware so this is resolved.

Appreciate all the replies.