nullable,

src/main/java/com/loafle/bridge/discoveryport/DiscoveryPort.java

@@ -17,7 +17,7 @@ public class DiscoveryPort {
     private long id;
 
     @ManyToOne
-    @JoinColumn
+    @JoinColumn(nullable = false)
     @JsonIgnore
     private DiscoveryHost host;
     public DiscoveryHost getHost() {

src/main/java/com/loafle/bridge/discoveryport/ServiceScanHistory.java

@@ -21,8 +21,8 @@ public class ServiceScanHistory {
     @Temporal(TemporalType.TIMESTAMP)
     private Date createDate;
 
-    @ManyToOne(fetch = FetchType.LAZY)
-    @JoinColumn
+    @ManyToOne
+    @JoinColumn(nullable = false)
     @JsonIgnore
     private DiscoveryPort port;
 
@@ -34,8 +34,6 @@ public class ServiceScanHistory {
     @Enumerated(EnumType.STRING)
     private DirectionType direction;
 
-
-
     @Lob
     @Column(nullable = false)
     private byte[] packet;