I'm running an application on WildFly server version 19.0.0.Final on CentOS 7. This application was working fine, but I run this almost 2 months later, and I'm getting this error where I didn't find any duplicate data sources in standalone.xml
14:21:06,641 ERROR [org.jboss.as.controller.management-operation] (Controller Boot Thread) WFLYCTL0013: Operation ("add") failed - address: ([("deployment" => "application.war")]) - failure description: "WFLYCTL0212: Duplicate resource [("deployment" => "application.war")]"
14:21:06,647 FATAL [org.jboss.as.server] (Controller Boot Thread) WFLYSRV0056: Server boot has failed in an unrecoverable manner; exiting. See previous messages for details.
From the stack trace which you have provided, it seems the issue is related to the deployment and not related to the data source.
if multiple deployment-scanner are defined then make sure that they are pointing to different locations
If Multiple deployment-scanner would be defined pointing to the same path or parent directory's path, which results in multiple deployment attempts of the same war file causing the exception.