System status Changing the FortiGate firmware
FortiGate-50A Installation and Configuration Guide 57
If you are reverting to a previous FortiOS version (for example, reverting from FortiOS
v2.50 to FortiOS v2.36) you might not be able to restore the previous configuration
from the backup configuration file.
To revert to a previous firmware version using the web-based manager
1Copy the firmware image file to your management computer.
2Log into the FortiGate web-based manager as the admin administrative user.
3Go to System > Status.
4Select Firmware Upgrade .
5Type the path and filename of the previous firmware image file, or select Browse and
locate the file.
6Select OK.
The FortiGate unit uploads the firmware image file, reverts to the old firmware version,
resets the configuration, restarts, and displays the FortiGate login. This process takes
a few minutes.
7Log into the web-based manager.
8Go to System > Status and check the Firmware Version to confirm that the firmware
is successfully installed.
9Restore your configuration.
For information about restoring your configuration, see “Restoring system settings” on
page 64.
10 Update antivirus and attack definitions. For information about antivirus and attack
definitions, see “Manually initiating antivirus and attack definitions updates” on
page 75.
Reverting to a previous firmware version using the CLI
This procedure reverts your FortiGate unit to its factory default configuration and
deletes NIDS user-defined signatures, web content lists, email filtering lists, and
changes to replacement messages.
Before beginning this procedure you can:
• Back up the FortiGate unit configuration using the command execute backup
config.
• Back up the NIDS user defined signatures using the command execute backup
nidsuserdefsig
• Back up web content and email filtering lists. For infor mation, see the FortiGate
Content Protection Guide.
If you are reverting to a previous FortiOS version (for example, reverting from FortiOS
v2.50 to FortiOS v2.36) you might not be able to restore your previous configuration
from the backup configuration file.
Note: Installing firmware replaces the current antivirus and attack definitions with the definitions
included with the firmware release that you are installing. After you install new firmware, use the
procedure “Manually initiating antivirus and attack definitions updates” on page 75 to make sure
that antivirus and attack definitions are up to date.