I thought tonight I’ll spend a night xmodem-ing my router as my IOS upgrade failed. Apparently, this teaches me something good.

Upgrade ROMMON initialized
Entering rommon> prompt after several failed attempts to boot an IOS image.
Please check your internal/external flash drives for the correct IOS image
and issue 'reset' at the rommon> prompt to re-try the boot process.
rommon 1 > help
alias               set and display aliases command
boot                boot up an external process
break               set/show/clear the breakpoint
confreg             configuration register utility
cont                continue executing a downloaded image
context             display the context of a loaded image
cookie              display contents of motherboard cookie PROM in hex
dev                 list the device table
dir                 list files in file system
dis                 disassemble instruction stream
dnld                serial download a program module
frame               print out a selected stack frame
help                monitor builtin command help
history             monitor command history
iomemset            set IO memory percent
meminfo             main memory information
repeat              repeat a monitor command
reset               system reset
rommon-pref         Select ROMMON
set                 display the monitor variables
showmon             display currently selected ROM monitor
stack               produce a stack trace
sync                write monitor environment to NVRAM
sysret              print out info from last system return
tftpdnld            tftp image download
unalias             unset an alias
unset               unset a monitor variable
xmodem              x/ymodem image download
rommon 2 > showmon

ReadOnly ROMMON version is:
System Bootstrap, Version 12.4(13r)T, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2006 by cisco Systems, Inc.

Upgrade ROMMON version is:
System Bootstrap, Version 12.4(13r)T11, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2009 by cisco Systems, Inc.

Upgrade ROMMON currently running
Upgrade ROMMON is selected for next boot
rommon 3 > IP_ADDRESS=1.1.1.2
rommon 4 > IP_SUBNET_MASK=255.255.255.252
rommon 5 > DEFAULT_GATEWAY=1.1.1.1
rommon 6 > TFTP_SERVER=1.1.1.1
rommon 7 > TFTP_FILE=c2800nm-advsecurityk9-mz.124-22.YB2.bin
rommon 8 > TFTP_VERBOSE=2
rommon 9 > FE_PORT=0
rommon 10 > TFTP_CHECKSUM=1
rommon 11 > tftpdnld

          IP_ADDRESS: 1.1.1.2
      IP_SUBNET_MASK: 255.255.255.252
     DEFAULT_GATEWAY: 1.1.1.1
         TFTP_SERVER: 1.1.1.1
           TFTP_FILE: c2800nm-advsecurityk9-mz.124-22.YB2.bin
        TFTP_VERBOSE: Verbose
    TFTP_RETRY_COUNT: 18
        TFTP_TIMEOUT: 7200
       TFTP_CHECKSUM: Yes
Missing MAC address for variable TFTP_MACADDR
        TFTP_MACADDR: 00:26:cb:78:af:90
             FE_PORT: Fast Ethernet 0
       FE_SPEED_MODE: Auto

Invoke this command for disaster recovery only.
WARNING: all existing data in all partitions on flash: will be lost!
Do you wish to continue? y/n:  [n]:  y

Performing tftpdnld over interface FastEthernet0/0
Initializing interface.
Interface link state up.
ARPing for 1.1.1.1
ARPing for 1.1.1.1
ARP reply for 1.1.1.1 received.  MAC address 00:15:c5:4e:c1:75.
Receiving c2800nm-advsecurityk9-mz.124-22.YB2.bin from 1.1.1.1 !!!!!!.
ARPing for 1.1.1.1
ARP reply for 1.1.1.1 received.  MAC address 00:15:c5:4e:c1:75!!!!!!!!!!!!!!!!!!!!
<cut>
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
File reception completed.
Validating checksum.
Copying file c2800nm-advsecurityk9-mz.124-22.YB2.bin to flash:.
program load complete, entry point: 0x8000f000, size: 0xcb80

Format: All system sectors written. OK...
Format: Operation completed successfully.

Format of flash: complete
program load complete, entry point: 0x8000f000, size: 0xcb80

rommon 19 > reset
c2811 platform with 262144 Kbytes of main memory
Main memory is configured to 64 bit mode with ECC enabled

Upgrade ROMMON initialized
program load complete, entry point: 0x8000f000, size: 0xcb80
program load complete, entry point: 0x8000f000, size: 0xcb80

program load complete, entry point: 0x8000f000, size: 0x247ebc4
Self decompressing the image : ##################### [OK]