fix

fe/fe-core/src/main/java/org/apache/doris/cloud/catalog/CloudEnv.java

@@ -407,6 +407,6 @@ public void dropFrontend(FrontendNodeType role, String host, int port) throws Dd
 
     @Override
     public void modifyFrontendHostName(String srcHost, int srcPort, String destHost) throws DdlException {
-        throw new DdlException("modify frontend host name is not supported in cloud mode");
+        throw new DdlException("Modifying frontend hostname is not supported in cloud mode");
     }
 }

fe/fe-core/src/main/java/org/apache/doris/cloud/system/CloudSystemInfoService.java

@@ -17,6 +17,8 @@
 
 package org.apache.doris.cloud.system;
 
+import org.apache.doris.analysis.ModifyBackendClause;
+import org.apache.doris.analysis.ModifyBackendHostNameClause;
 import org.apache.doris.catalog.Env;
 import org.apache.doris.catalog.ReplicaAllocation;
 import org.apache.doris.cloud.catalog.CloudEnv;
@@ -407,6 +409,16 @@ public void decommissionBackend(Backend backend) throws UserException {
         }
     }
 
+    @Override
+    public void modifyBackends(ModifyBackendClause alterClause) throws UserException {
+        throw new UserException("Modifying backends is not supported in cloud mode");
+    }
+
+    @Override
+    public void modifyBackendHost(ModifyBackendHostNameClause clause) throws UserException {
+        throw new UserException("Modifying backend hostname is not supported in cloud mode");
+    }
+
     @Override
     public void replayAddBackend(Backend newBackend) {
         super.replayAddBackend(newBackend);

regression-test/suites/cloud_p0/node_mgr/test_not_allowed_op.groovy

@@ -0,0 +1,75 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+suite('test_not_allowed_op', 'p0') {
+    if (!isCloudMode()) {
+        return;
+    }
+
+    // Test modifying frontend is not allowed
+    try {
+        // Get current frontend information
+        def frontendResult = sql_return_maparray """SHOW FRONTENDS"""
+        logger.info("Current frontends: ${frontendResult}")
+
+        // Extract the first frontend's information
+        def firstFrontend = frontendResult[0]
+        def frontendHost = firstFrontend['Host']
+        def frontendEditLogPort = firstFrontend['EditLogPort']
+
+        // Construct the frontend address
+        def frontendAddress = "${frontendHost}:${frontendEditLogPort}"
+        logger.info("Attempting to modify frontend: ${frontendAddress}")
+        def result = sql """ ALTER SYSTEM MODIFY FRONTEND "${frontendAddress}" HOSTNAME 'localhost' """
+        logger.info("Modify frontend result: ${result}")
+        throw new IllegalStateException("Expected exception was not thrown")
+    } catch (Exception e) {
+        assertTrue(e.getMessage().contains("Modifying frontend hostname is not supported in cloud mode"))
+    }
+
+    // Get current backend information
+    def backendResult = sql_return_maparray """SHOW BACKENDS"""
+    logger.info("Current backends: ${backendResult}")
+
+    // Extract the first backend's information
+    def firstBackend = backendResult[0]
+    def backendHost = firstBackend['Host']
+    def backendHeartbeatPort = firstBackend['HeartbeatPort']
+
+    // Construct the backend address
+    def backendAddress = "${backendHost}:${backendHeartbeatPort}"
+    // Test modifying backend is not allowed
+    try {
+        logger.info("Attempting to modify backend: ${backendAddress}")
+        def result = sql """ ALTER SYSTEM MODIFY BACKEND '${backendAddress}' SET("tag.location" = "tag1") """
+        logger.info("Modify backend result: ${result}")
+        throw new IllegalStateException("Expected exception was not thrown")
+    } catch (Exception e) {
+        logger.info("Caught expected exception: ${e.getMessage()}")
+        assertTrue(e.getMessage().contains("Modifying backends is not supported in cloud mode"))
+    }
+
+    // Test modifying backend hostname is not allowed
+    try {
+        sql """ ALTER SYSTEM MODIFY BACKEND "${backendAddress}" HOSTNAME 'localhost' """
+        throw new IllegalStateException("Expected exception was not thrown")
+    } catch (Exception e) {
+        assertTrue(e.getMessage().contains("Modifying backend hostname is not supported in cloud mode"))
+    }
+
+    logger.info("All tests for disallowed operations in cloud mode passed successfully")
+}