In principle, I/O fencing using storage reservations is not available in DataKeeper configuration and split brain can occur. Therefore, you need to take steps to prevent a split brain from occurring via the following controls.
Exclusive Control using IP Resources
IP resources have an exclusive control functionality using duplication checking to ensure the same IP resource is not activated on multiple nodes. This can be used to avoid a split brain with DataKeeper resources.
Adding an IP resources as a child resource to all DataKeeper resources in the hierarchy can prevent the DataKeeper resource from starting on multiple nodes at the same time.
This method can only be used in environments where all the nodes in the cluster reside in the same subnet. This is required to perform the duplicate IP address checking.
Exclusive Control with Quorum/Witness Functionality
You can use the quorum/witness functionality in LifeKeeper to prevent multiple nodes from becoming active at the same time.
For details, please refer to the Quorum/Witness topic in the Technical Documentation.