Advanced Boot and Backup Configuration Information > Downloading a New Software Version

Downloading a New Software Version
You can download a new software version in either of the following ways:
Use the Web Manager Æ Firmware Upgrade screen to download the image from an FTP server
When the image is downloaded by FTP, a script (saveimage) automatically extracts the filesystem from the image, mounts it, and copies the files to the removable flash. Since the current image is being run from one of the three-partitions sets, the downloaded image is stored in the other set of three partitions. The environment variable currentimage is changed so that the system boots from the new image.
The U-Boot monitor command net_boot boots the image from the TFTP server specified in the environment variables. After the image is downloaded by network boot, the root filesystem is in the RAMDISK, and the image can run even if no removable flash card is inserted.
From the command line, you can then run the create_cf script with the --doformat option to automatically save the image from RAMDISK into the removable flash. The script erases everything in the flash, partitions the flash, if necessary, formats the partitions, and copies the files currently in the RAMDISK into the corresponding image partitions. If the flash is already partitioned, you can choose where the image is saved using the option --imageN.

Advanced Boot and Backup Configuration Information > Downloading a New Software Version