Database Storage for Wait/Notify/Receive Notification Information
If your process engines are located on different machines, a database is required to store process instance state for inter-process communication. When process engines reside on different machines, they must share information about pending Wait/Receive Notification/Notify activities.
A database allows process engines to share process instance state information across machines in a domain. Your deployment configuration must specify a database for process engine storage if you expect process instances on different machines to have corresponding Wait/Receive Notification/Notify activities.
See
for more information on specifying a database for process engine storage when configuring your deployment.