Issue

• I wonder where is this error message:

09:43:31,867 ERROR [org.jboss.as.server] (Controller Boot Thread) JBAS015956: Caught exception during boot: org.jboss.as.controller.persistence.ConfigurationPersistenceException: JBAS014676: Failed to parse configuration
        at org.jboss.as.controller.persistence.XmlConfigurationPersister.load(XmlConfigurationPersister.java:141) [jboss-as-controller.jar:7.5.1.Final-redhat-3]
        at org.jboss.as.server.ServerService.boot(ServerService.java:330) [jboss-as-server.jar:7.5.1.Final-redhat-3]
        at org.jboss.as.controller.AbstractControllerService$1.run(AbstractControllerService.java:263) [jboss-as-controller.jar:7.5.1.Final-redhat-3]
        at java.lang.Thread.run(Thread.java:745) [rt.jar:1.7.0_79]
Caused by: javax.xml.stream.XMLStreamException: ParseError at [row,col]:[307,13]
Message: JBAS014724: Missing required attribute(s): default-data-store
        at org.jboss.as.controller.parsing.ParseUtils.missingRequired(ParseUtils.java:135) [jboss-as-controller.jar:7.5.1.Final-redhat-3]
        at org.jboss.as.ejb3.subsystem.EJB3Subsystem15Parser.parseTimerService(EJB3Subsystem15Parser.java:114)
        at org.jboss.as.ejb3.subsystem.EJB3Subsystem15Parser.readElement(EJB3Subsystem15Parser.java:69)
        at org.jboss.as.ejb3.subsystem.EJB3Subsystem12Parser.readElement(EJB3Subsystem12Parser.java:105)
        at org.jboss.as.ejb3.subsystem.EJB3Subsystem12Parser.readElement(EJB3Subsystem12Parser.java:71)
        at org.jboss.staxmapper.XMLMapperImpl.processNested(XMLMapperImpl.java:110) [staxmapper.jar:1.1.0.Final-redhat-3]

• Where is the default-data-store and what is use of it ?