When would you need this: When you want to upgrade the IOS file and you do not have TFTP of FTP servers around, so you turn to the good old console for the upgrade.

Special Requirements: The router flash size should be adequate for the new IOS image, and you should have enough RAM in the router for the operation and temporary storage of the new IOS file.

It is recommended that you backup the old IOS file before the upgrade using this procedure, and backup the configuration too using this procedure. And keep in mind that this procedure is not recommended. It is recommended that you upgrade using a TFTP or FTP server. This is because it takes a long time and you do not see an error when it occurs until the copying is finished.

1. Create a console connection with the default settings (9600 baud, 8 databits, 0 parity bits, 1 stop bit, no flow control).

2. Change the baud rate of the console port to its maximum 115,200

Router#set baud = 115200

3. Reset the console port

Router#reset

Now you will not get anymore output on the screen until you finish step 3.

4. Change the connection speed of the HyperTerminal. Disconnect and reconnect with the baud rate of 115200 with all the rest of the settings mentioned in step 1.

5. Prepare the router for the reception of the new IOS file

Router#upload xmodem

Now you will have the following message,

Ready for X/Modem upload ...

[note: no status bar for xmodem transfers, 

abort with Control-X or break]

6. Send the file from your terminal emulation software. This is done by selecting Transfer from the upper menu of HyperTerminal and then Send File. In the Send File dialog box, choose the new IOS file using the Browse button, choose Xmodem as the protocol, and then press Send.

The sending operation may take a long time, and there is no progress indicator in the router, but you will have a progress indicator in the HyperTerminal. After the copying is finished, you will receive a message,

upload: succeeded (XXX seconds)

Now the new IOS file is in the router’s RAM.

7. If you don’t have enough space in the router’s flash for the old and new files, delete the old IOS file (this is not recommended though),

Router#delete flash:OLD_IOS_FILE.bin

8. Save the new IOS file to the flash,

Router#save file = NEW_IOS_FILE.bin

the NEW_IOS_FILE.bin is a name of your choice for the new IOS file.

9. Direct the router to load the new IOS file at the next startup,

Router(config)#no boot system

Router(config)#boot system flash NEW_IOS_FILE.bin

10. You can reload the router now, but remember to change back the settings of the HyperTerminal to the 9600 baud to get output on your screen after the reload. If you type the reload command, the router might ask you if you want to save the configuration. You should be very cautious here. The reason is that if the router is in boot mode for instance, it is a subset of the full Cisco IOS software which is running and there is no routing functionality. Therefore, all the routing configuration is gone in the running configuration and if you save the configuration at this time, then you erase the good startup-configuration in NVRAM and replace it by the incomplete running-configuration. Save the configuration only if you are sure that you have the full configuration in the output of show run. It is NOT necessary to save the configuration.

Note: Instead reloading, you can issue 'boot' command that will boot the new software image. 

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