Troubleshooting Tip: Configuration deployment fails to ADOM after the FortiGate upgrade

Description

This article describes an issue where configuration installation from FortiManager to an ADOM fails after upgrading a FortiGate from FortiOS v7.4.11 to FortiOS v7.6.6.

During the installation process, the Install Preview or Install Progress Report may show errors because the command syntax has changed between the two FortiOS versions.

Scope

FortiGate, FortiManager.

Solution

After the FortiGate upgrade, FortiManager may attempt to install the previous command syntax, resulting in installation failures similar to the following:

FGT (Vdom1) config switch-controller global

FGT (global) set vlan-optimization enable

command parse error before 'enable'

Command fail. Return code -61

FGT (global) end

FGT (Vdom1) end

In FortiOS v7.6.6, the syntax of the vlan-optimization setting under config switch-controller global has changed. 
In v7.4.11, the syntax is 'enable'.
Whereas in v7.6.6, it is changed to 'configured' on the FortiGate end.

FortiManager still holds the configuration retrieved from the earlier FortiOS version and continues to push the old keyword, causing the deployment to fail.

To resolve the issue, update the configuration on the FortiGate using the new syntax and then synchronize the configuration with FortiManager:

1. Configure the new syntax on the FortiGate:

Run the following commands on the affected VDOM:

config vdom

edit Vdom1

config switch-controller global

set vlan-optimization configured

end

end

2. Retrieve the configuration in FortiManager:

From FortiManager:

1. Select the FortiGate device.

2. Perform a Full Retrieve Config operation.

3. Wait for the retrieval to complete successfully.

3. Verify the installation preview:

After the configuration retrieval:

1. Open Install Preview.

2. Confirm that FortiManager no longer attempts to send the old command.

3. Proceed with the configuration installation.

The configuration installation to the ADOM should now complete successfully without command parsing errors.