When installing the latest firmware or older firmware you can use either the GUI or the CLI. This recipe shows how to install the firmware of your FortiMail unit using the CLI from a TFTP server.
This recipe assumes that the firmware image file you want to install is already copied to the root directory of the TFTP server.
Go to Fortinet Service & Support for the latest firmware. Whether you are upgrading or downgrading your firmware, it is strongly recommended to back up the configuration and mail data. For more information about configuration backups, see “Backup and Restore” in the FortiMail Administration Guide.
Firmware upgrade requires that you follow the supported firmware upgrade path, as FortiMail units running older firmware versions may not successfully install the latest firmware version. See the appropriate FortiMail Release Notes for the correct upgrade path.