Dear,
1st get the image that with the feature-set that meet your needs with care regarding RAM/FLASH components, for professional advice use Cisco feature Navigator website (http://www.cisco.com/go/fn/)
Here are the steps:
-copy the downloaded image file to your TFTP directory
-Make sure that there is IP connectivity between the router --> TFTP
-keep the boot-loader file on the bootflash
-Copy the image file from the TFTP to your Diskx:
-use verify command to check the image checksum with/without MD5 option (depending on your IOS)
-use the following commands to configure primary and backup image boot sequence
Primary image for boot:
boot system disk0:c7200-mm.xx-xx.bin
Backup image for boot:
boot system disk0:c7200-mm.xx-bkup.bin
Boot Loader:
boot bootldr bootflash:c7200-kboot-mz.122-27.bin
Best Regards,
Mounir Mohamed