5.2 Managing the Cisco File System  
  5.2.5 Managing IOS images using TFTP  
Occasionally the router will need to have the IOS upgraded or restored. When a router first arrives, the IOS should be backed up. This IOS image can be stored in a central server with other IOS images. These images can be used to restore or upgrade the IOS on the routers and switches in the internetwork.

This server should have a TFTP service running. The IOS backup can be initiated from the privileged EXEC mode with the copy flash tftp command.

The router will prompt the user to enter the IP address of the TFTP server. When prompted for the filename of the IOS image on the server, the router may then prompt to erase flash. This often happens if there is not sufficient flash available for the new image. As the image is erased from flash, a series of “e’s” will appear to show the erase process.

As each datagram of the IOS image file is downloaded, an “!” will be displayed. This IOS image is several megabytes and may take some time.

The new flash image will be verified after it is downloaded. The router is now ready to be reloaded to use the new IOS image.

 

Lab Activity

Lab Exercise: Managing IOS Images with TFTP

In this lab, the students will backup a copy of a router IOS from flash to a TFTP server.

 
 

Web Links

Loading and Maintaining System Images

http://www.cisco.com/en/US/products/sw/ iosswrel/ps1835/products_configuration_guide_ chapter09186a00800c6c63.html#xtocid23