fix: attach Airflow container to network before starting

composer_local_dev/environment.py

@@ -1132,10 +1132,33 @@ def start(self, assert_not_running=True):
             self.ensure_container_is_attached_to_network(db_container)
             LOG.info(f"Database started!")
 
-        container = self.start_container(
-            self.container_name, assert_not_running
-        )
+        # Attach to network before starting to avoid DNS resolution race:
+        # entrypoint runs "airflow db migrate" immediately on container start,
+        # so the container must already be on the Docker network at that point.
+        container = self.get_or_create_container(self.container_name)
+        if (
+            assert_not_running
+            and container.status == constants.ContainerStatus.RUNNING
+        ):
+            raise errors.EnvironmentAlreadyRunningError(self.name) from None
         self.ensure_container_is_attached_to_network(container)
+        try:
+            container.start()
+        except docker.errors.APIError as err:
+            logging.debug(
+                "Starting environment failed with Docker API error.",
+                exc_info=True,
+            )
+            if (
+                err.status_code == constants.SERVER_ERROR_CODE
+                and "port is already allocated" in str(err)
+            ):
+                container.remove()
+                raise errors.ComposerCliError(
+                    constants.PORT_IN_USE_ERROR.format(port=self.port)
+                )
+            error = f"Environment ({self.container_name}) failed to start with an error: {err}"
+            raise errors.EnvironmentStartError(error) from None
         self.wait_for_start()
         self.print_start_message()