<ul class="contains-task-list">
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox"> I have searched the <a href="https://github.com/apache/dubbo/issues">issues</a> of this repository and believe that this is not a duplicate.</li>
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox"> I have checked the <a href="https://github.com/apache/dubbo/blob/master/FAQ.md">FAQ</a> of this repository and believe that this is not a duplicate.</li>
</ul>
<h3 dir="auto">Environment</h3>
<ul dir="auto">
<li>Dubbo version: 2.7.8</li>
<li>Operating System version: mac</li>
<li>Java version: 1.8</li>
</ul>
<h3 dir="auto">Steps to reproduce this issue</h3>
<p dir="auto">使用Dubbo的多注册中心和Zone 功能，一直在两个注册中心中负载，设置zone 不生效 ，设置 preferred: true 不生效<br>
consumer</p>
<div class="highlight highlight-source-yaml notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="dubbo:
  consumer:
    check: false
  registries:
    test:
      id: test
      protocol: zookeeper
      address: zookeeper://localhost:2181?zone=test
      use-as-config-center: false
      preferred: true
      registry.zone: test
    dev:
      id: dev
      protocol: zookeeper
      address: dev-zk1.zk.com:2181
      use-as-config-center: false
      registry.zone: dev
  config:
    multiple: true
"><pre class="notranslate"><span class="pl-ent">dubbo</span>:
  <span class="pl-ent">consumer</span>:
    <span class="pl-ent">check</span>: <span class="pl-c1">false</span>
  <span class="pl-ent">registries</span>:
    <span class="pl-ent">test</span>:
      <span class="pl-ent">id</span>: <span class="pl-s">test</span>
      <span class="pl-ent">protocol</span>: <span class="pl-s">zookeeper</span>
      <span class="pl-ent">address</span>: <span class="pl-s">zookeeper://localhost:2181?zone=test</span>
      <span class="pl-ent">use-as-config-center</span>: <span class="pl-c1">false</span>
      <span class="pl-ent">preferred</span>: <span class="pl-c1">true</span>
      <span class="pl-ent">registry.zone</span>: <span class="pl-s">test</span>
    <span class="pl-ent">dev</span>:
      <span class="pl-ent">id</span>: <span class="pl-s">dev</span>
      <span class="pl-ent">protocol</span>: <span class="pl-s">zookeeper</span>
      <span class="pl-ent">address</span>: <span class="pl-s">dev-zk1.zk.com:2181</span>
      <span class="pl-ent">use-as-config-center</span>: <span class="pl-c1">false</span>
      <span class="pl-ent">registry.zone</span>: <span class="pl-s">dev</span>
  <span class="pl-ent">config</span>:
    <span class="pl-ent">multiple</span>: <span class="pl-c1">true</span>
</pre></div>
<p dir="auto">provider1</p>
<div class="highlight highlight-source-yaml notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="dubbo:
  protocol:
    port: 12322
    name: dubbo
  config:
    multiple: true
  registry:
    id: dev
    zone: dev
    use-as-config-center: false
    address: zookeeper://dev-zk1.zk.com:2181
  config-center:
    address: zookeeper://dev-zk1.zk.com:2181
  metadata-report:
    address:  zookeeper://dev-zk1.zk.com:2181"><pre class="notranslate"><span class="pl-ent">dubbo</span>:
  <span class="pl-ent">protocol</span>:
    <span class="pl-ent">port</span>: <span class="pl-c1">12322</span>
    <span class="pl-ent">name</span>: <span class="pl-s">dubbo</span>
  <span class="pl-ent">config</span>:
    <span class="pl-ent">multiple</span>: <span class="pl-c1">true</span>
  <span class="pl-ent">registry</span>:
    <span class="pl-ent">id</span>: <span class="pl-s">dev</span>
    <span class="pl-ent">zone</span>: <span class="pl-s">dev</span>
    <span class="pl-ent">use-as-config-center</span>: <span class="pl-c1">false</span>
    <span class="pl-ent">address</span>: <span class="pl-s">zookeeper://dev-zk1.zk.com:2181</span>
  <span class="pl-ent">config-center</span>:
    <span class="pl-ent">address</span>: <span class="pl-s">zookeeper://dev-zk1.zk.com:2181</span>
  <span class="pl-ent">metadata-report</span>:
    <span class="pl-ent">address</span>:  <span class="pl-s">zookeeper://dev-zk1.zk.com:2181</span></pre></div>
<p dir="auto">provider1</p>
<div class="highlight highlight-source-yaml notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="dubbo:
  protocol:
    port: 12311
    name: dubbo
  config:
    multiple: true
  registry:
    id: test
    zone: test
    use-as-config-center: false
    address: zookeeper://localhost:2181
  config-center:
    address: zookeeper://localhost:2181
  metadata-report:
    address: zookeeper://localhost:2181
"><pre class="notranslate"><span class="pl-ent">dubbo</span>:
  <span class="pl-ent">protocol</span>:
    <span class="pl-ent">port</span>: <span class="pl-c1">12311</span>
    <span class="pl-ent">name</span>: <span class="pl-s">dubbo</span>
  <span class="pl-ent">config</span>:
    <span class="pl-ent">multiple</span>: <span class="pl-c1">true</span>
  <span class="pl-ent">registry</span>:
    <span class="pl-ent">id</span>: <span class="pl-s">test</span>
    <span class="pl-ent">zone</span>: <span class="pl-s">test</span>
    <span class="pl-ent">use-as-config-center</span>: <span class="pl-c1">false</span>
    <span class="pl-ent">address</span>: <span class="pl-s">zookeeper://localhost:2181</span>
  <span class="pl-ent">config-center</span>:
    <span class="pl-ent">address</span>: <span class="pl-s">zookeeper://localhost:2181</span>
  <span class="pl-ent">metadata-report</span>:
    <span class="pl-ent">address</span>: <span class="pl-s">zookeeper://localhost:2181</span>
</pre></div>
<h3 dir="auto">Expected Result</h3>
<p dir="auto">应该优先调用    preferred: true 的注册中心</p>
<h3 dir="auto">Actual Result</h3>
<p dir="auto">两个注册中心的服务随机调用</p>
<ul class="contains-task-list">
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox"> I have searched the <a href="https://github.com/apache/dubbo/issues">issues</a> of this repository and believe that this is not a duplicate.</li>
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox"> I have checked the <a href="https://github.com/apache/dubbo/blob/master/FAQ.md">FAQ</a> of this repository and believe that this is not a duplicate.</li>
</ul>
<h3 dir="auto">Steps to reproduce this issue</h3>
<p dir="auto"><a href="http://dubbo.apache.org/zh-cn/docs/2.7/user/preface/architecture/" rel="nofollow">http://dubbo.apache.org/zh-cn/docs/2.7/user/preface/architecture/</a></p>
<ol dir="auto">
<li>源码导读章节没了</li>
<li>左侧目录中，2.7 -&gt; 开发手册 下的其他章节均跳转到首页</li>
</ol>