diff --git a/java-agent/instrumentation/datastax-cassandra-3/src/test/groovy/CassandraClientTest.groovy b/java-agent/instrumentation/datastax-cassandra-3/src/test/groovy/CassandraClientTest.groovy
index 7dae164d44..8ec49d7512 100644
--- a/java-agent/instrumentation/datastax-cassandra-3/src/test/groovy/CassandraClientTest.groovy
+++ b/java-agent/instrumentation/datastax-cassandra-3/src/test/groovy/CassandraClientTest.groovy
@@ -18,8 +18,6 @@ class CassandraClientTest extends AgentTestRunner {
 
   @Shared
   Cluster cluster
-  @Shared
-  int port = 9142
 
   def setupSpec() {
     /*
@@ -28,7 +26,7 @@ class CassandraClientTest extends AgentTestRunner {
      started in container like we do for memcached. Note: this will complicate things because
      tests would have to assume they run under shared Cassandra and act accordingly.
       */
-    EmbeddedCassandraServerHelper.startEmbeddedCassandra(120000L)
+    EmbeddedCassandraServerHelper.startEmbeddedCassandra(EmbeddedCassandraServerHelper.CASSANDRA_RNDPORT_YML_FILE, 120000L)
 
     cluster = EmbeddedCassandraServerHelper.getCluster()
 
@@ -124,7 +122,7 @@ class CassandraClientTest extends AgentTestRunner {
         "$Tags.SPAN_KIND" Tags.SPAN_KIND_CLIENT
         "$Tags.PEER_HOSTNAME" "localhost"
         "$Tags.PEER_HOST_IPV4" "127.0.0.1"
-        "$Tags.PEER_PORT" port
+        "$Tags.PEER_PORT" EmbeddedCassandraServerHelper.getNativeTransportPort()
         "$Tags.DB_TYPE" "cassandra"
         "$Tags.DB_INSTANCE" keyspace
         "$Tags.DB_STATEMENT" statement
diff --git a/java-agent/instrumentation/dropwizard/src/test/groovy/DropwizardTest.groovy b/java-agent/instrumentation/dropwizard/src/test/groovy/DropwizardTest.groovy
index 1f5e79cab8..f8b43f615d 100644
--- a/java-agent/instrumentation/dropwizard/src/test/groovy/DropwizardTest.groovy
+++ b/java-agent/instrumentation/dropwizard/src/test/groovy/DropwizardTest.groovy
@@ -11,6 +11,7 @@ import io.opentelemetry.auto.instrumentation.jaxrs2.JaxRsAnnotationsDecorator
 import io.opentelemetry.auto.instrumentation.servlet3.Servlet3Decorator
 import io.opentelemetry.auto.test.asserts.TraceAssert
 import io.opentelemetry.auto.test.base.HttpServerTest
+import io.opentelemetry.auto.test.utils.PortUtils
 import io.opentelemetry.sdk.trace.SpanData
 import org.eclipse.jetty.servlet.ServletHandler
 
@@ -29,9 +30,11 @@ class DropwizardTest extends HttpServerTest<DropwizardTestSupport, Servlet3Decor
 
   @Override
   DropwizardTestSupport startServer(int port) {
+    println "Port: $port"
     def testSupport = new DropwizardTestSupport(testApp(),
       null,
-      ConfigOverride.config("server.applicationConnectors[0].port", "$port"))
+      ConfigOverride.config("server.applicationConnectors[0].port", "$port"),
+      ConfigOverride.config("server.adminConnectors[0].port", PortUtils.randomOpenPort().toString()))
     testSupport.before()
     return testSupport
   }
diff --git a/java-agent/instrumentation/netty-4.0/src/test/groovy/Netty40ClientTest.groovy b/java-agent/instrumentation/netty-4.0/src/test/groovy/Netty40ClientTest.groovy
index 6c1537a96b..c1e49885de 100644
--- a/java-agent/instrumentation/netty-4.0/src/test/groovy/Netty40ClientTest.groovy
+++ b/java-agent/instrumentation/netty-4.0/src/test/groovy/Netty40ClientTest.groovy
@@ -61,7 +61,7 @@ class Netty40ClientTest extends HttpClientTest<NettyHttpClientDecorator> {
 
   def "connection error (unopened port)"() {
     given:
-    def uri = new URI("http://localhost:$UNUSABLE_PORT/")
+    def uri = new URI("http://127.0.0.1:$UNUSABLE_PORT/") // Use numeric address to avoid ipv4/ipv6 confusion
 
     when:
     runUnderTrace("parent") {
@@ -93,7 +93,7 @@ class Netty40ClientTest extends HttpClientTest<NettyHttpClientDecorator> {
               } catch (ClassNotFoundException e) {
                 // Older versions use 'java.net.ConnectException' and do not have 'io.netty.channel.AbstractChannel$AnnotatedConnectException'
               }
-              errorTags errorClass, "Connection refused: localhost/127.0.0.1:$UNUSABLE_PORT"
+              errorTags errorClass, "Connection refused: /127.0.0.1:$UNUSABLE_PORT"
             }
           }
         }