diff --git a/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceRrdMigratorOnline.java b/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceRrdMigratorOnline.java
index 6c535d1..1e94ca1 100644
--- a/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceRrdMigratorOnline.java
+++ b/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceRrdMigratorOnline.java
@@ -254,6 +254,7 @@ public class SnmpInterfaceRrdMigratorOnline extends AbstractOnmsUpgrade {
                 reason = "Unknown";
             }
             log("Reason(%s): %s\n", t.getClass().getName(), reason);
+            t.printStackTrace();
         } finally {
             db.cleanUp();
         }
diff --git a/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceUpgrade.java b/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceUpgrade.java
index 7b4209a..9e575f2 100644
--- a/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceUpgrade.java
+++ b/core/upgrade/src/main/java/org/opennms/upgrade/implementations/SnmpInterfaceUpgrade.java
@@ -232,6 +232,11 @@ public class SnmpInterfaceUpgrade {
      * @return true, if the interface directory should be merged
      */
     public boolean shouldMerge() {
+        // If the ifName and the ifDescr are null at the same time, OpenNMS is going to create a directory like this:
+        // /var/opennms/rrd/snmp/10/null or /var/opennms/rrd/snmp/10/null-00029906ced7
+        if (ifDescr == null && ifName == null) {
+            ifName = "null";
+        }
         // An SnmpInterfaceUpgrade entry only exist for SNMP interfaces with MAC Address.
         // For this reason, if the old directory exist and the label of the old interface is different than the new one,
         // that means, the interface statistics must be merged.