en/docs/v2.7/user/references/registry/index.xml

<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Apache Dubbo – Registry Server References</title><link>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/</link><description>Recent content in Registry Server References on Apache Dubbo</description><generator>Hugo -- gohugo.io</generator><language>en</language><atom:link href="https://dubbo.apache.org/en/docs/v2.7/user/references/registry/index.xml" rel="self" type="application/rss+xml"/><item><title>Docs: Nacos Registry Center</title><link>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/nacos/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/nacos/</guid><description>
&lt;p>Nacos is a very important registry center for Dubbo ecosystem, &lt;a href="https://github.com/apache/incubator-dubbo/tree/master/dubbo-registry/dubbo-registry-nacos">&lt;code>dubbo-registry-nacos&lt;/code>&lt;/a> is the implementation of Nacos integration to Nacos.&lt;/p>
&lt;h2 id="prepare-work">Prepare Work&lt;/h2>
&lt;p>When you integrate &lt;a href="https://github.com/apache/incubator-dubbo/tree/master/dubbo-registry/dubbo-registry-nacos">&lt;code>dubbo-registry-nacos&lt;/code>&lt;/a> into your Dubbo project, please Make sure the Nacos service is started in the background. If you are not familiar with the basic use of Nacos, you can refer to &lt;a href="https://nacos.io/en-us/docs/quick-start.html">Nacos Quick Start&lt;/a>. It is recommended to use the version equal or above Nacos &lt;code>1.0.0&lt;/code>.&lt;/p>
&lt;h2 id="quick-start">Quick Start&lt;/h2>
&lt;p>The steps for Dubbo to integrate Nacos as a registry center are very simple. The general steps can be divided into &amp;ldquo;add Maven dependencies&amp;rdquo; and &amp;ldquo;configure registry center&amp;rdquo;.&lt;/p>
&lt;h3 id="add-maven-dependencies">Add Maven Dependencies&lt;/h3>
&lt;p>First, you need to add the &lt;code>dubbo-registry-nacos&lt;/code> Maven dependency to your project&amp;rsquo;s &lt;code>pom.xml&lt;/code> file, and we strongly recommend that you use Dubbo &lt;code>2.6.5&lt;/code>:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dependencies&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> ...
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- Dubbo Nacos registry dependency --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>com.alibaba&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>dubbo-registry-nacos&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>0.0.2&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- Keep latest Nacos client version --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>com.alibaba.nacos&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>nacos-client&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>[0.6.1,)&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- Dubbo dependency --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>com.alibaba&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>dubbo&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>2.6.5&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- Alibaba Spring Context extension --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>com.alibaba.spring&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>spring-context-support&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>1.0.2&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> ...
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/dependencies&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>When you add &lt;code>dubbo-registry-nacos&lt;/code> to your project, you don&amp;rsquo;t need to explicitly program the service discovery and registration logic. The actual implementation is provided by the three-party package.&lt;/p>
&lt;h3 id="configure-registry-center">Configure Registry Center&lt;/h3>
&lt;p>Assuming your Dubbo app uses the Spring Framework assembly, there are two configuration options available: &lt;a href="https://mercyblitz.github.io/2018/01/18/Dubbo-%E5%A4%96%E9%83%A8%E5%8C%96%E9%85%8D%E7%BD%AE/">Dubbo Spring Externalization Configuration&lt;/a> and the Spring XML configuration file.&lt;/p>
&lt;h3 id="dubbo-spring-externalization-configurationhttpsmercyblitzgithubio20180118dubbo-e5a496e983a8e58c96e9858de7bdae">&lt;a href="https://mercyblitz.github.io/2018/01/18/Dubbo-%E5%A4%96%E9%83%A8%E5%8C%96%E9%85%8D%E7%BD%AE/">Dubbo Spring Externalization Configuration&lt;/a>&lt;/h3>
&lt;p>The Dubbo Spring externalization configuration is a new feature introduced by Dubbo &lt;code>2.5.8&lt;/code> that automatically generates and binds Dubbo configuration beans through the Spring &lt;code>Environment&lt;/code> property, simplifying configuration and lowering the microservice development threshold.&lt;/p>
&lt;p>Assuming your Nacos Server is also running on server &lt;code>10.20.153.10&lt;/code> and using the default Nacos service port &lt;code>8848&lt;/code>, you only need to adjust the &lt;code>dubbo.registry.address&lt;/code> property as follows:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-properties" data-lang="properties">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#586e75">## Other properties remain unchanged&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#586e75">## Nacos registry address&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>dubbo.registry.address &lt;span style="color:#719e07">=&lt;/span> &lt;span style="color:#2aa198">nacos://10.20.153.10:8848&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>...
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Then, restart your Dubbo app, Dubbo&amp;rsquo;s service provider and consumer information can be displayed on the Nacos console:&lt;/p>
&lt;p>&lt;img src="https://dubbo.apache.org/imgs/blog/dubbo-registry-nacos-1.png" alt="dubbo-registry-nacos-1.png">&lt;/p>
&lt;p>As shown in the figure, the information whose service name prefix is &lt;code>providers:&lt;/code> is the meta information of the service provider, and the &lt;code>consumers:&lt;/code> represents the meta information of the service consumer. Click on &amp;ldquo;&lt;strong>Details&lt;/strong>&amp;rdquo; to view service status details:&lt;/p>
&lt;p>&lt;img src="https://dubbo.apache.org/imgs/blog/dubbo-registry-nacos-2.png" alt="dubbo-registry-nacos-2.png">&lt;/p>
&lt;p>If you are using the Spring XML configuration file to assemble the Dubbo registry, please refer to the next section.&lt;/p>
&lt;h3 id="spring-xml-configuration-file">Spring XML Configuration File&lt;/h3>
&lt;p>Similar to &lt;a href="https://mercyblitz.github.io/2018/01/18/Dubbo-%E5%A4%96%E9%83%A8%E5%8C%96%E9%85%8D%E7%BD%AE/">Dubbo Spring Externalization Configuration&lt;/a>, just adjust the &lt;code>address&lt;/code> attribute to configure:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#719e07">&amp;lt;?xml version=&amp;#34;1.0&amp;#34; encoding=&amp;#34;UTF-8&amp;#34;?&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;beans&lt;/span> xmlns=&lt;span style="color:#2aa198">&amp;#34;http://www.springframework.org/schema/beans&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> xmlns:xsi=&lt;span style="color:#2aa198">&amp;#34;http://www.w3.org/2001/XMLSchema-instance&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> xmlns:dubbo=&lt;span style="color:#2aa198">&amp;#34;http://dubbo.apache.org/schema/dubbo&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> xsi:schemaLocation=&lt;span style="color:#2aa198">&amp;#34;http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd&amp;#34;&lt;/span>&lt;span style="color:#268bd2">&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- Provider application information for calculating dependencies --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:application&lt;/span> name=&lt;span style="color:#2aa198">&amp;#34;dubbo-provider-xml-demo&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- Use Nacos as Registry Center --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;nacos://10.20.153.10:8848&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> ...
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/beans&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>After restarting the Dubbo app, you can also find that the registration meta-information of the service provider and consumer is presented on the Nacos console:&lt;/p>
&lt;p>&lt;img src="https://dubbo.apache.org/imgs/blog/dubbo-registry-nacos-3.png" alt="dubbo-registry-nacos-3.png">&lt;/p>
&lt;p>&lt;strong>Additional information&lt;/strong>: since &lt;a href="mailto:nacos-server@1.0.0">nacos-server@1.0.0&lt;/a>, support client report instance info which contains particular key in metadata to control some behavior.&lt;/p>
&lt;p>Such as:&lt;br>
&lt;code>preserved.heart.beat.timeout&lt;/code> : The time of the instance from healthy to unhealthy after heartbeat is not send.(unit:millisecond) &lt;br>
&lt;code>preserved.ip.delete.timeout&lt;/code> : The time of the instance is dropped by server after the heartbeat is not send.(unit:millisecond)&lt;br>
&lt;code>preserved.heart.beat.interval&lt;/code> : The interval of the instance to send heartbeat (unit:millisecond)&lt;br>
&lt;code>preserved.instance.id.generator&lt;/code>: The id generator strategy, value set as &lt;code>snowflake&lt;/code> means the id will be increment from 0.&lt;br>
&lt;code>preserved.register.source&lt;/code> : Reserved key, not used at now.&lt;/p>
&lt;p>This feature will be support since Dubbo@&lt;code>2.7.10&lt;/code>, you can use this feature by append param in nacos address.
Such as: &lt;code>nacos://10.20.153.10:8848?preserved.heart.beat.timeout=15000&amp;amp;preserved.ip.delete.timeout=30000&amp;amp;preserved.heart.beat.interval=10000&lt;/code>&lt;/p></description></item><item><title>Docs: Zookeeper Registry Server</title><link>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/zookeeper/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/zookeeper/</guid><description>
&lt;p>&lt;a href="http://zookeeper.apache.org">Zookeeper&lt;/a> is the child project of apache hadoop. Since it offers tree-like directory service and supports change notification, it&amp;rsquo;s suitable to use it as dubbo&amp;rsquo;s registry server. It&amp;rsquo;s a field-proven product, therefore it&amp;rsquo;s recommended to use it in the production environment. &lt;sup id="fnref:1">&lt;a href="#fn:1" class="footnote-ref" role="doc-noteref">1&lt;/a>&lt;/sup>&lt;/p>
&lt;p>&lt;img src="https://dubbo.apache.org/imgs/user/zookeeper.jpg" alt="/user-guide/images/zookeeper.jpg">&lt;/p>
&lt;p>Description on registration procedure:&lt;/p>
&lt;ul>
&lt;li>When service provider boots up: write service URL address under directory &lt;code>/dubbo/com.foo.BarService/providers&lt;/code>&lt;/li>
&lt;li>When service consumer boots up: subscribe to &lt;code>/dubbo/com.foo.BarService/providers&lt;/code> for provider&amp;rsquo;s URL addresses. At the same time, write consumer&amp;rsquo;s URL address under &lt;code>/dubbo/com.foo.BarService/consumers&lt;/code>.&lt;/li>
&lt;li>When monitor center boots up: subscribe to &lt;code>/dubbo/com.foo.BarService&lt;/code> for the URL addresses from all providers and consumers.&lt;/li>
&lt;/ul>
&lt;p>The following abilities are supported:&lt;/p>
&lt;ul>
&lt;li>When provider stops by accident, registry server can remove its info automatically.&lt;/li>
&lt;li>When registry server reboots, all registration data and subscription requests can be recovered automatically.&lt;/li>
&lt;li>When session is expired, all registration data and subscription requests can be recovered automatically.&lt;/li>
&lt;li>When &lt;code>&amp;lt;dubbo:registry check=&amp;quot;false&amp;quot; /&amp;gt;&lt;/code> is configured, failed requests for subscription and registration will be recorded and kept retrying in the background.&lt;/li>
&lt;li>Configure &lt;code>&amp;lt;dubbo:registry username=&amp;quot;admin&amp;quot; password=&amp;quot;1234&amp;quot; /&amp;gt;&lt;/code> for zookeeper login.&lt;/li>
&lt;li>Configure &lt;code>&amp;lt;dubbo:registry group=&amp;quot;dubbo&amp;quot; /&amp;gt;&lt;/code> for dubbo&amp;rsquo;s root node on zookeeper. Default root node will be used if it&amp;rsquo;s not specified.&lt;/li>
&lt;li>Support to use wildcard &lt;code>*&lt;/code> in &lt;code>&amp;lt;dubbo:reference group=&amp;quot;*&amp;quot; version=&amp;quot;*&amp;quot; /&amp;gt;&lt;/code> in order to subscribe all groups and all versions for the services to be referenced.&lt;/li>
&lt;/ul>
&lt;h2 id="how-to-use">How to Use&lt;/h2>
&lt;p>Add zookeeper client dependency in both provider and consumer:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>org.apache.zookeeper&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>zookeeper&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>3.3.3&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or &lt;a href="https://repo1.maven.org/maven2/org/apache/zookeeper/zookeeper">download&lt;/a> directly from apache.&lt;/p>
&lt;p>Dubbo supports two zookeeper clients: zkclient and curator:&lt;/p>
&lt;h3 id="use-zkclient">Use zkclient&lt;/h3>
&lt;p>Since &lt;code>2.2.0&lt;/code> dubbo uses zkclient by default, in order to improve the robustness. &lt;a href="https://github.com/sgroschupf/zkclient">zkclient&lt;/a> is a zookeeper client implementation open-sourced by Datameer.&lt;/p>
&lt;p>&lt;strong>Note: The implementation of zkclient has been removed in the 2.7.x version. If you want to use the zkclient client, you need to extend it yourself.&lt;/strong>&lt;/p>
&lt;p>Default configuration:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> ... client=&lt;span style="color:#2aa198">&amp;#34;zkclient&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-sh" data-lang="sh">&lt;span style="display:flex;">&lt;span>dubbo.registry.client&lt;span style="color:#719e07">=&lt;/span>zkclient
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-sh" data-lang="sh">&lt;span style="display:flex;">&lt;span>zookeeper://10.20.153.10:2181?client&lt;span style="color:#719e07">=&lt;/span>zkclient
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>In order to use it, need to explicitly declare the following maven dependency or &lt;a href="https://repo1.maven.org/maven2/com/github/sgroschupf/zkclient">download its client&lt;/a>.&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>com.github.sgroschupf&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>zkclient&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>0.1&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;h3 id="use-curator">Use curator&lt;/h3>
&lt;p>Since &lt;code>2.3.0&lt;/code> dubbo also supports curator but explicit configuration is required. &lt;a href="https://github.com/Netflix/curator">Curator&lt;/a> is the zookeeper client open-sourced by Netflix.&lt;/p>
&lt;p>In order to switch to curator, use the configuration below:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> ... client=&lt;span style="color:#2aa198">&amp;#34;curator&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-sh" data-lang="sh">&lt;span style="display:flex;">&lt;span>dubbo.registry.client&lt;span style="color:#719e07">=&lt;/span>curator
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-sh" data-lang="sh">&lt;span style="display:flex;">&lt;span>zookeeper://10.20.153.10:2181?client&lt;span style="color:#719e07">=&lt;/span>curator
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Also need to explicitly add maven dependency or directly &lt;a href="https://repo1.maven.org/maven2/com/netflix/curator/curator-framework">download&lt;/a> the jar:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;groupId&amp;gt;&lt;/span>com.netflix.curator&lt;span style="color:#268bd2">&amp;lt;/groupId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;artifactId&amp;gt;&lt;/span>curator-framework&lt;span style="color:#268bd2">&amp;lt;/artifactId&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;version&amp;gt;&lt;/span>1.1.10&lt;span style="color:#268bd2">&amp;lt;/version&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/dependency&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Zookeeper single node configuration:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;zookeeper://10.20.153.10:2181&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;zookeeper&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;10.20.153.10:2181&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Zookeeper cluster configuration：&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;zookeeper://10.20.153.10:2181?backup=10.20.153.11:2181,10.20.153.12:2181&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;zookeeper&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;10.20.153.10:2181,10.20.153.11:2181,10.20.153.12:2181&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Configure single zookeeper to serve as multiple registry servers:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> id=&lt;span style="color:#2aa198">&amp;#34;chinaRegistry&amp;#34;&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;zookeeper&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;10.20.153.10:2181&amp;#34;&lt;/span> group=&lt;span style="color:#2aa198">&amp;#34;china&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> id=&lt;span style="color:#2aa198">&amp;#34;intlRegistry&amp;#34;&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;zookeeper&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;10.20.153.10:2181&amp;#34;&lt;/span> group=&lt;span style="color:#2aa198">&amp;#34;intl&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;h2 id="zookeeper-installation">Zookeeper Installation&lt;/h2>
&lt;p>Pls. refer to &lt;a href="https://dubbo.apache.org/en/docs/v2.7/admin/install/zookeeper/">zookeeper install manual&lt;/a> for how to install zookeeper based registry server. To set it up, specify &lt;code>dubbo.registry.address&lt;/code> to &lt;code>zookeeper://127.0.0.1:2181&lt;/code> in &lt;code>conf/dubbo.properties&lt;/code> for both provider and consumer (you can refer to &lt;a href="https://dubbo.apache.org/en/docs/v2.7/user/quick-start/">quick start&lt;/a>) after install a zookeeper server.&lt;/p>
&lt;h2 id="declaration-of-reliability">Declaration of Reliability&lt;/h2>
&lt;p>A home-brewed service registry server is used in Alibaba instead of zookeeper server. Zookeeper based registry center does not have long-run practice within Alibaba, therefore we cannot guarantee its reliability. Zookeeper registry server is provided for dubbo community, and its reliability relies on zookeeper itself largely.&lt;/p>
&lt;h2 id="declaration-of-compatibility">Declaration of Compatibility&lt;/h2>
&lt;p>The original designed data structure for zookeeper in &lt;code>2.0.8&lt;/code> has the limitation that data type cannot extended, it&amp;rsquo;s redesigned in &lt;code>2.0.9&lt;/code>. But at the same time incompatibility is introduced, thereby &lt;code>2.0.9&lt;/code> is required for all service providers and service consumers.&lt;/p>
&lt;p>Since &lt;code>2.2.0&lt;/code> zkclient is used by default, therefore its dependency is needed.&lt;/p>
&lt;p>Since &lt;code>2.3.0&lt;/code> curator is supported as alternative option.&lt;/p>
&lt;div class="footnotes" role="doc-endnotes">
&lt;hr>
&lt;ol>
&lt;li id="fn:1">
&lt;p>Suggest to use &lt;code>2.3.3&lt;/code> or above for zookeeper registry client&amp;#160;&lt;a href="#fnref:1" class="footnote-backref" role="doc-backlink">&amp;#x21a9;&amp;#xfe0e;&lt;/a>&lt;/p>
&lt;/li>
&lt;/ol>
&lt;/div></description></item><item><title>Docs: Multicast Registry</title><link>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/multicast/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/multicast/</guid><description>
&lt;p>Multicast registry doesn&amp;rsquo;t require to setup any central node. Just like IP address broadcast, dubbo service providers and consumers can discover each other through this mechanism.&lt;/p>
&lt;p>&lt;img src="https://dubbo.apache.org/imgs/user/multicast.jpg" alt="/user-guide/images/multicast.jpg">&lt;/p>
&lt;ol start="0">
&lt;li>Service provider broadcasts its address when it boots up.&lt;/li>
&lt;li>Service consumer broadcasts its subscription request when it boots up.&lt;/li>
&lt;li>Once service provider receives subscription request, it unicasts its own address to the corresponding consumer, if &lt;code>unicast=false&lt;/code> is set, then broadcast will be used instead.&lt;/li>
&lt;li>When service consumer receives provider&amp;rsquo;s address, it can start RPC invocation on the received address.&lt;/li>
&lt;/ol>
&lt;p>Multicast is limited to network topology, and is only suitable for development purpose or small deployment. The valid multcast addresses scope is: 224.0.0.0 - 239.255.255.255.&lt;/p>
&lt;h2 id="configuration">Configuration&lt;/h2>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;multicast://224.5.6.7:1234&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;multicast&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;224.5.6.7:1234&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>In order to avoid multicast as much as possible, dubbo uses unicast for address information from service provider to service consumer, if there are multiple consumer processes on one single machine, consumers need to set &lt;code>unicast=false&lt;/code>, otherwise only one consumer can be able to receive the address info:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:application&lt;/span> name=&lt;span style="color:#2aa198">&amp;#34;demo-consumer&amp;#34;&lt;/span>&lt;span style="color:#268bd2">&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:parameter&lt;/span> key=&lt;span style="color:#2aa198">&amp;#34;unicast&amp;#34;&lt;/span> value=&lt;span style="color:#2aa198">&amp;#34;false&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/dubbo:application&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:consumer&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:parameter&lt;/span> key=&lt;span style="color:#2aa198">&amp;#34;unicast&amp;#34;&lt;/span> value=&lt;span style="color:#2aa198">&amp;#34;false&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/dubbo:consumer&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div></description></item><item><title>Docs: Redis Registry Server</title><link>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/redis/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/redis/</guid><description>
&lt;h1 id="redis-registry-server">Redis Registry Server&lt;/h1>
&lt;p>It is a registry server implementation &lt;sup id="fnref:1">&lt;a href="#fn:1" class="footnote-ref" role="doc-noteref">1&lt;/a>&lt;/sup> based on redis &lt;sup id="fnref:2">&lt;a href="#fn:2" class="footnote-ref" role="doc-noteref">2&lt;/a>&lt;/sup>.&lt;/p>
&lt;p>&lt;img src="https://dubbo.apache.org/imgs/user/dubbo-redis-registry.jpg" alt="/user-guide/images/dubbo-redis-registry.jpg">&lt;/p>
&lt;p>Use key/map structure in redis to save the registration info:&lt;/p>
&lt;ul>
&lt;li>Main key for service name and type&lt;/li>
&lt;li>Key in the map is URL address&lt;/li>
&lt;li>Value in the map is the expiration time. Monitor center uses it to track and remove dirty data &lt;sup id="fnref:3">&lt;a href="#fn:3" class="footnote-ref" role="doc-noteref">3&lt;/a>&lt;/sup>&lt;/li>
&lt;/ul>
&lt;p>Publish/Subscribe events in redis is leveraged for data change notification:&lt;/p>
&lt;ul>
&lt;li>Distinguish event type with event&amp;rsquo;s value: &lt;code>register&lt;/code>, &lt;code>unregister&lt;/code>, &lt;code>subscribe&lt;/code>, &lt;code>unsubscribe&lt;/code>.&lt;/li>
&lt;li>Regular subscriber subscribes the particular key presenting service provider, then will receive &lt;code>register&lt;/code> and &lt;code>unregister&lt;/code> events fired from the specified service.&lt;/li>
&lt;li>Monitor center subscribes &lt;code>/dubbo/*&lt;/code> via &lt;code>psubscribe&lt;/code>, then will receive all change notifications from all services.&lt;/li>
&lt;/ul>
&lt;p>Procedure:&lt;/p>
&lt;ol start="0">
&lt;li>When service provider boots up, it adds its address under &lt;code>Key:/dubbo/com.foo.BarService/providers&lt;/code>.&lt;/li>
&lt;li>Then service provider sends &lt;code>register&lt;/code> event to &lt;code>Channel:/dubbo/com.foo.BarService/providers&lt;/code>&lt;/li>
&lt;li>When service consumer boots up, it subscribe events &lt;code>register&lt;/code> and &lt;code>unregister&lt;/code> from &lt;code>Channel:/dubbo/com.foo.BarService/providers&lt;/code>&lt;/li>
&lt;li>Then service consumer add its address under &lt;code>Key:/dubbo/com.foo.BarService/consumers&lt;/code>&lt;/li>
&lt;li>When service consumer receives events &lt;code>register&lt;/code> and &lt;code>unregister&lt;/code>, it will fetch provider&amp;rsquo;s addresses from &lt;code>Key:/dubbo/com.foo.BarService/providers&lt;/code>&lt;/li>
&lt;li>When monitor center boots up, it subscribes events &lt;code>register&lt;/code>, &lt;code>unregister&lt;/code>, &lt;code>subscribe&lt;/code>, and &lt;code>unsubsribe&lt;/code>.&lt;/li>
&lt;li>After monitor center receives &lt;code>register&lt;/code> and &lt;code>unregister&lt;/code>, it fetches provider&amp;rsquo;s addresses from &lt;code>Key:/dubbo/com.foo.BarService/providers&lt;/code>&lt;/li>
&lt;li>After monitor center receives &lt;code>subscribe&lt;/code> and &lt;code>unsubscribe&lt;/code>, it fetches consumer&amp;rsquo;s addresses from &lt;code>Key:/dubbo/com.foo.BarService/consumers&lt;/code>&lt;/li>
&lt;/ol>
&lt;h2 id="configuration">Configuration&lt;/h2>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;redis://10.20.153.10:6379&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;redis://10.20.153.10:6379?backup=10.20.153.11:6379,10.20.153.12:6379&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;redis&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;10.20.153.10:6379&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> protocol=&lt;span style="color:#2aa198">&amp;#34;redis&amp;#34;&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;10.20.153.10:6379,10.20.153.11:6379,10.20.153.12:6379&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;h2 id="options">Options&lt;/h2>
&lt;ul>
&lt;li>Config key&amp;rsquo;s prefix in redis via &lt;code>&amp;lt;dubbo:registry group=&amp;quot;dubbo&amp;quot; /&amp;gt;&lt;/code>, the default value is &lt;code>dubbo&lt;/code>.&lt;/li>
&lt;li>Config redis cluster strategy via &lt;code>&amp;lt;dubbo:registry cluster=&amp;quot;replicate&amp;quot; /&amp;gt;&lt;/code>, the default value is &lt;code>failover&lt;/code>:
&lt;ul>
&lt;li>&lt;code>failover&lt;/code>: when read/write error happens, try another instance, require the cluster to support data replication.&lt;/li>
&lt;li>&lt;code>replicate&lt;/code>: client writes to all nodes of the cluster, but only peeks a random node for read. The cluster doesn&amp;rsquo;t need to take care of data replication, but may require more nodes and higher performance for each node, compared to option 1.&lt;/li>
&lt;/ul>
&lt;/li>
&lt;/ul>
&lt;h2 id="declaration-of-reliability">Declaration of Reliability&lt;/h2>
&lt;p>A home-brewed service registry server is used in Alibaba instead of redis server. Redis based registry center does not have long-run practice within Alibaba, therefore we cannot guarantee its reliability. This registry server implementation is provided for dubbo community, and its reliability relies on redis itself largely.&lt;/p>
&lt;h2 id="installation">Installation&lt;/h2>
&lt;p>Pls. refer to &lt;a href="https://dubbo.apache.org/en/docs/v2.7/admin/install/redis/">redis install manual&lt;/a> for how to install a redis based registry server. To set it up, specify &lt;code>dubbo.registry.address&lt;/code> to &lt;code>redis://127.0.0.1:6379&lt;/code> in &lt;code>conf/dubbo.properties&lt;/code> for both provider and consumer (you can refer to &lt;a href="https://dubbo.apache.org/en/docs/v2.7/user/quick-start/">quick start&lt;/a>) after install a redis server.&lt;/p>
&lt;div class="footnotes" role="doc-endnotes">
&lt;hr>
&lt;ol>
&lt;li id="fn:1">
&lt;p>Support since &lt;code>2.1.0&lt;/code>&amp;#160;&lt;a href="#fnref:1" class="footnote-backref" role="doc-backlink">&amp;#x21a9;&amp;#xfe0e;&lt;/a>&lt;/p>
&lt;/li>
&lt;li id="fn:2">
&lt;p>&lt;a href="http://redis.io">Redis&lt;/a> is a high performance KV cache server&amp;#160;&lt;a href="#fnref:2" class="footnote-backref" role="doc-backlink">&amp;#x21a9;&amp;#xfe0e;&lt;/a>&lt;/p>
&lt;/li>
&lt;li id="fn:3">
&lt;p>Heartbeat mechanism is used to detect the dirty data in redis. It requires time among servers must be sync in advanced, otherwise expiration check may inaccurate, plus, heartbeats may add extra pressure on servers.&amp;#160;&lt;a href="#fnref:3" class="footnote-backref" role="doc-backlink">&amp;#x21a9;&amp;#xfe0e;&lt;/a>&lt;/p>
&lt;/li>
&lt;/ol>
&lt;/div></description></item><item><title>Docs: Simple Registry Server</title><link>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/simple/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs/v2.7/user/references/registry/simple/</guid><description>
&lt;p>Simple registry server itself is a regular dubbo service. In this way, third-party dependency is unnecessary, and communication keeps consistent at the same moment.&lt;/p>
&lt;h2 id="configuration">Configuration&lt;/h2>
&lt;p>Register simple registry server as dubbo service:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#719e07">&amp;lt;?xml version=&amp;#34;1.0&amp;#34; encoding=&amp;#34;UTF-8&amp;#34;?&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;beans&lt;/span> xmlns=&lt;span style="color:#2aa198">&amp;#34;http://www.springframework.org/schema/beans&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> xmlns:xsi=&lt;span style="color:#2aa198">&amp;#34;http://www.w3.org/2001/XMLSchema-instance&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> xmlns:dubbo=&lt;span style="color:#2aa198">&amp;#34;http://dubbo.apache.org/schema/dubbo&amp;#34;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> xsi:schemaLocation=&lt;span style="color:#2aa198">&amp;#34;http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd&amp;#34;&lt;/span>&lt;span style="color:#268bd2">&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- application info configuration --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:application&lt;/span> name=&lt;span style="color:#2aa198">&amp;#34;simple-registry&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- service protocol configuration --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:protocol&lt;/span> port=&lt;span style="color:#2aa198">&amp;#34;9090&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- service configuration --&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:service&lt;/span> interface=&lt;span style="color:#2aa198">&amp;#34;org.apache.dubbo.registry.RegistryService&amp;#34;&lt;/span> ref=&lt;span style="color:#2aa198">&amp;#34;registryService&amp;#34;&lt;/span> registry=&lt;span style="color:#2aa198">&amp;#34;N/A&amp;#34;&lt;/span> ondisconnect=&lt;span style="color:#2aa198">&amp;#34;disconnect&amp;#34;&lt;/span> callbacks=&lt;span style="color:#2aa198">&amp;#34;1000&amp;#34;&lt;/span>&lt;span style="color:#268bd2">&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:method&lt;/span> name=&lt;span style="color:#2aa198">&amp;#34;subscribe&amp;#34;&lt;/span>&lt;span style="color:#268bd2">&amp;gt;&amp;lt;dubbo:argument&lt;/span> index=&lt;span style="color:#2aa198">&amp;#34;1&amp;#34;&lt;/span> callback=&lt;span style="color:#2aa198">&amp;#34;true&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&amp;lt;/dubbo:method&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;dubbo:method&lt;/span> name=&lt;span style="color:#2aa198">&amp;#34;unsubscribe&amp;#34;&lt;/span>&lt;span style="color:#268bd2">&amp;gt;&amp;lt;dubbo:argument&lt;/span> index=&lt;span style="color:#2aa198">&amp;#34;1&amp;#34;&lt;/span> callback=&lt;span style="color:#2aa198">&amp;#34;false&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&amp;lt;/dubbo:method&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;/dubbo:service&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#586e75">&amp;lt;!-- simple registry server implementation, register other implementation if cluster ability is a requirement--&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span> &lt;span style="color:#268bd2">&amp;lt;bean&lt;/span> id=&lt;span style="color:#2aa198">&amp;#34;registryService&amp;#34;&lt;/span> class=&lt;span style="color:#2aa198">&amp;#34;org.apache.dubbo.registry.simple.SimpleRegistryService&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;/beans&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Reference simple registry server service:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;127.0.0.1:9090&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:service&lt;/span> interface=&lt;span style="color:#2aa198">&amp;#34;org.apache.dubbo.registry.RegistryService&amp;#34;&lt;/span> group=&lt;span style="color:#2aa198">&amp;#34;simple&amp;#34;&lt;/span> version=&lt;span style="color:#2aa198">&amp;#34;1.0.0&amp;#34;&lt;/span> ... &lt;span style="color:#268bd2">&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;p>Or:&lt;/p>
&lt;div class="highlight">&lt;pre tabindex="0" style="color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4;">&lt;code class="language-xml" data-lang="xml">&lt;span style="display:flex;">&lt;span>&lt;span style="color:#268bd2">&amp;lt;dubbo:registry&lt;/span> address=&lt;span style="color:#2aa198">&amp;#34;127.0.0.1:9090&amp;#34;&lt;/span> group=&lt;span style="color:#2aa198">&amp;#34;simple&amp;#34;&lt;/span> version=&lt;span style="color:#2aa198">&amp;#34;1.0.0&amp;#34;&lt;/span> &lt;span style="color:#268bd2">/&amp;gt;&lt;/span>
&lt;/span>&lt;/span>&lt;/code>&lt;/pre>&lt;/div>&lt;h2 id="applicability">Applicability&lt;/h2>
&lt;p>This &lt;code>SimpleRegistryService&lt;/code> is just a simple implementation for register server, and it doesn&amp;rsquo;t have cluster support. It is useful for the implementation reference for the custom registry server, but not suitable for use in production environment directly.&lt;/p></description></item></channel></rss>