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Managing IOS images using TFTP

Managing IOS images using TFTP
5.2.5
The page will show students how to store IOS images on a TFTP server.
The IOS may need to be backed up, upgraded, or restored using the copy command. When a router first arrives, the IOS should be backed up. The IOS backup can be initiated from the privileged EXEC mode with the copy flash tftp command. 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 a network. This server should have a TFTP service running. The router will prompt the user to enter the IP address of the TFTP server and to specify a destination filename.
To restore or upgrade the IOS from the server use the copy tftp flash command as shown in Figure . The router will prompt the user to enter the IP address of the TFTP server. Next, the router will prompt the user for the filename of the IOS image on the server. The router may then prompt the user 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 exclamation mark (!) will be displayed. This IOS image is several megabytes and may take a long time to download.
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.
The Lab Activity will allow students to back up a copy of a router IOS onto a TFTP server.
The next page will show students how ROMmon and Xmodem can be used to manage IOS images.

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