WAS v8.5 > Troubleshoot > Troubleshooting Service integration > Problem solving for messaging engine data storesAvoiding failover problems when we use DB2 v8.2 with HADR as your data store
Use this task to avoid problems that can occur when a messaging engine that is configured to use DB2 v8.2 with the High Availability Data Recovery (HADR) feature for its data store terminates if the DB2 database fails over. If we use the High Availability Data Recovery (HADR) feature of DB2, note the following restrictions:
- The messaging engine default messaging provider supports only the synchronous and near-synchronoous synchronization modes of HADR. The default messaging provider does not support asynchronous HADR configurations.
- The TAKEOVER BY FORCE command is permitted only when the standby database is in peer state, or when the standby database had last changed from peer state to its current state (such as disconnected state).