Event Description Error
If you attempt to onboard or create an FTD HA pair in CDO, the HA pair may fail to form and you may see an error with the following message:
Event description: CD App Sync error is Cisco Threat Response is enabled on Active but not on Standby
If you see this error, then one or both of the devices within the HA pair is not configured to allow the devices to send events to the a Cisco cloud server such as CDO, Firepower Threat Response, Or the Cisco Success Network.
You must enable the Send Events to the Cisco Cloud feature from the FDM UI. See the Configuring Cloud Services chapter of the Firepower Device Manager Configuration Guide of the version you are running for more information.