diff --git a/testing/node-driver/src/main/java/net/corda/testing/driver/SharedMemoryIncremental.java b/testing/node-driver/src/main/java/net/corda/testing/driver/SharedMemoryIncremental.java
index 7d97f33140..88e6e726d7 100644
--- a/testing/node-driver/src/main/java/net/corda/testing/driver/SharedMemoryIncremental.java
+++ b/testing/node-driver/src/main/java/net/corda/testing/driver/SharedMemoryIncremental.java
@@ -76,8 +76,7 @@ public class SharedMemoryIncremental extends PortAllocation {
                 newValue = (oldValue + 1);
             }
             boolean reserveSuccess = UNSAFE.compareAndSwapLong(null, startingAddress, oldValue, newValue);
-            boolean portAvailable = isLocalPortAvailable(newValue);
-            loopSuccess = reserveSuccess && portAvailable;
+            loopSuccess = reserveSuccess && isLocalPortAvailable(newValue);
         } while (!loopSuccess);
 
         return (int) newValue;