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操作步骤如下：
1. k8s环境下，consumer端开启mesh模式
2. consumer端需要调用多个provider
3. provider有应用级注册和接口级注册，并且需要的provider不再同一个namespace下
4. 原有项目存在dubbo2.6与3.1多版本间的相互调用，在开启消费端mesh（dubbo3.1）后，无法调用到2.6的服务提供者

**问题：**

1. 如何实现在一个consumer下，调用多个namespace下的provider，并且provider有应用级注册和接口级注册
2. dubbo3.1消费端在开启mesh后，如何调用版本是2.6的服务提供者
*/
    boolean init() default true;
    /**
     * Whether to make connection when the client is created, the default value is false
     */
    boolean lazy() default false;
    /**
     * Export an stub service for event dispatch, default value is false.
     * <p>
     * see org.apache.dubbo.rpc.Constants#STUB_EVENT_METHODS_KEY
     */
    boolean stubevent() default false;
    /**
     * Whether to reconnect if connection is lost, if not specify, reconnect is enabled by default, and the interval
     * for retry connecting is 2000 ms
     * <p>
     * see org.apache.dubbo.remoting.Constants#DEFAULT_RECONNECT_PERIOD
     */
    String reconnect() default "";
    /**
     * Whether to stick to the same node in the cluster, the default value is false
     * <p>
     * see Constants#DEFAULT_CLUSTER_STICKY
     */
    boolean sticky() default false;
    /**
     * How the proxy is generated, legal values include: jdk, javassist
     */
    String proxy() default "";
    /**