fix dependency conflict
diff --git a/dubbo-samples-grpc/dubbo-samples-reactor/pom.xml b/dubbo-samples-grpc/dubbo-samples-reactor/pom.xml
index 73864d6..e113971 100644
--- a/dubbo-samples-grpc/dubbo-samples-reactor/pom.xml
+++ b/dubbo-samples-grpc/dubbo-samples-reactor/pom.xml
@@ -28,10 +28,10 @@
     <properties>
         <source.level>1.8</source.level>
         <target.level>1.8</target.level>
-        <dubbo.version>2.7.7</dubbo.version>
+        <dubbo.version>3.0.0-20210226-SNAPSHOT</dubbo.version>
         <junit.version>4.12</junit.version>
         <spring.version>4.3.16.RELEASE</spring.version>
-        <grpc.version>1.19.0</grpc.version>
+        <grpc.version>1.31.1</grpc.version>
     </properties>
 
     <dependencyManagement>
@@ -67,6 +67,12 @@
         <dependency>
             <groupId>org.apache.dubbo</groupId>
             <artifactId>dubbo</artifactId>
+            <exclusions>
+                <exclusion>
+                    <groupId>io.netty</groupId>
+                    <artifactId>netty-all</artifactId>
+                </exclusion>
+            </exclusions>
         </dependency>
 
         <dependency>