Steps to upgrade Fortigate Firewall.

1.    Visit  https://docs.fortinet.com/upgrade-tool

2.    Select your current FortiGate product, FortiOS Version, and Select What FortiOS Version you
want to  upgrade.

3. Click
on GO it will show Recommended Upgrade Path

you need to follow the path that is specified as above.

4.  You need to download all
recommended Upgrade Path Firmware Version from

Fortinet support portal.  https://support.fortinet.com/

Follow below heighted path to download-

 

5. To download firmware image, click on HTTPS Checksum for your current
FortiGate Product.

1.    By using above step you can download all recommended Firmware
versions step by step.

 

Now
Login to your FortiGate Admin Dashboard.

Navigate
to —–>System—–>Firmware

Click
on upload –

Select
Firmware file

It will
ask for confirmation for Backup after click on Backup and Upgrade.

Click on continue.

It will start Backup and Upgrade.