database is open on another node in a mode not compatible with
  this node

  Explanation:  Another node has already opened the database and
  the database uses some feature that makes it impossible to
  concurrently open the database on this node.  For example, if
  Row Cache is enabled, then all nodes must be able to share
  memory (OpenVMS Galaxy).  If global buffers are enabled then
  every node that is a member of the same Galaxy system must use
  the same global buffer parameters when opening the database.