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Appendix B      ROM Monitor
ROM Monitor Commands
Step 7Enter y to start the download. Successive exclamation points (!!!!!!) indicate that 
the download is occurring. The router reboots when the download is complete.
Updating in Cisco IOS EXEC Mode
Step 1Download the ROMMON image from CCO, and place it on your TFTP server.
Step 2In EXEC mode, save the current configuration, using the copy running-config 
startup-config command.
Step...

 
Appendix B      ROM Monitor
Command Descriptions
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78-5372-06 meminfo             main memory information
repeat              repeat a monitor command
reset               system reset
set                 display the monitor variables
stack               produce a stack trace
sync                write monitor environment to NVRAM
sysret              print out info from last system return
tftpdnld            tftp image download
unalias...

 
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Appendix B      ROM Monitor
Disaster Recovery with TFTP Download
Disaster Recovery with TFTP Download
The standard way to load new software on your router is using the copy tftp flash 
privileged EXEC command from the Cisco IOS software command-line interface 
(CLI). However, if the router is unable to boot the Cisco IOS software, you can 
load new software while in ROM monitor mode.
This section describes how to load a Cisco IOS...

 
Appendix B      ROM Monitor
Disaster Recovery with TFTP Download
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NoteThe commands described in this section are case sensitive and must be entered 
exactly as shown.
Required Variables
These variables must be set with these commands before using the tftpdnld 
command.
Variable Command
IP address of the router.IP_ADDRESS=ip_address
Subnet mask of the routerIP_SUBNET_MASK=ip_address
IP address of the default gateway of the...

 
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Appendix B      ROM Monitor
Disaster Recovery with TFTP Download
Optional Variables
The following variables should be set with these commands before using the 
tftpdnld command.
Variable Command
Configures how the router displays file 
download progress.
0—No progress is displayed.
1—Exclamation points (!!!) are 
displayed to indicate file download 
progress. This is the default setting.
2—Detailed progress is displayed 
during the...

 
Appendix B      ROM Monitor
Using the TFTP Download Command Without Writing the Image to Flash Memory
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Using the TFTP Download Command Without 
Writing the Image to Flash Memory
Follow the steps below to do download new file in ROM monitor mode.
Step 1Use the appropriate commands to enter all the required variables and any optional 
variables described earlier in this section.
Step 2Enter the tftpdnld command as follows:
rommon 1 >...

 
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Appendix B      ROM Monitor
Configuration Register
Configuration Register
The virtual configuration register is in nonvolatile RAM (NVRAM) and has the 
same functionality as other Cisco routers. You can view or modify the virtual 
configuration register from either the ROM monitor or the operating system 
software. Within ROM monitor, you can change the configuration register by 
entering the register value in hexadecimal format, or...

 
Appendix B      ROM Monitor
Console Download
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do you wish to change the configuration? y/n  [n]:  y
enable  “diagnostic mode”? y/n  [n]:  y
enable  “use net in IP bcast address”? y/n  [n]:  
enable  “load rom after netboot fails”? y/n  [n]:  
enable  “use all zero broadcast”? y/n  [n]:  
enable  “break/abort has effect”? y/n  [n]:  
enable  “ignore system config info”? y/n  [n]:  
change console baud rate? y/n...

 
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Appendix B      ROM Monitor
Console Download
Note If you are using a PC to download a Cisco IOS image over the router console port 
at 115,200 bps, ensure that the PC serial port is using a 16550 universal 
asynchronous transmitter/receiver (UART). If the PC serial port is not using a 
16550 UART, we recommend using a speed of 38,400 or less when downloading 
a Cisco IOS image over the console port.
Command Description
The following...

 
Appendix B      ROM Monitor
Debug Commands
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Follow the steps below to run Xmodem:
Step 1Move the image file to the local drive where the Xmodem will execute.
Step 2Enter the xmodem command.
Error Reporting
Because the ROM monitor console download uses the console to perform the data 
transfer, error messages are displayed on the console only when the data transfer 
is terminated. 
If an error does occur during a data transfer, the...