The server can preempt server or client operations for a higher priority operation when a mount point is in use and no others are available, or access to a specific volume is required. When an operation is preempted, it is canceled.
You can use the QUERY MOUNT command to see the status of the volume for the mount point.
By default, preemption is enabled on the server. To disable preemption, specify NOPREEMPT in the server options file. If you specify this option, the BACKUP DB command, and the export and import commands are the only operations that can preempt other operations.