Recover/Upgrade a Router IOS Using USB Flash Drive

This procedure demonstrates using a USB Flash Drive to recover/upgrade an IOS image using the USB port of a router.
The example shows recovering a router that is in ROMMON with no available IOS on the Compact Flash.
If you are using the USB Flash Drive to upgrade the IOS, skip steps 4-6.

Note Note:   Cisco routers support FAT32 file system. Format the USB Flash Drive using FAT32.

Step 1:  Get the correct IOS image onto the laptop's desktop. (Figure 1)

Figure 1: IOS image on desktop

Step 2:  
Copy the IOS image from the laptop's desktop to the USB Flash Drive. (Figure 2)

Figure 2: Copy IOS Image to USB Flash Drive

Step 3:  Plug the USB Flash Drive into an available USB port on the router. For this example, the USB Flash Drive is plugged into slot 0.

Step 4:  Use the dev command from ROMMON to see the available devices.

Step 5:  Use the dir devicename command to ensure the router can read the device.

Step 6:  Use the boot device:filename command to boot directly to the IOS image on the USB Flash Drive.

Step 7:  Once the router completes the boot, copy the image from the USB Flash Drive to the Compact Flash of the router using the copy source destination command.

Step 8:  Verify the copied image using the show flash command. Set boot statements if applicable.

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