| <rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Apache Dubbo – 6 - Transport</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/</link><description>Recent content in 6 - Transport on Apache Dubbo</description><generator>Hugo -- gohugo.io</generator><language>en</language><atom:link href="https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/index.xml" rel="self" type="application/rss+xml"/><item><title>Docs3-V2: 6-1 - Server Connection Failed</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/1/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/1/</guid><description> |
| <p>Network communication layer, failed to connect to the service provider service</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>The service provider&rsquo;s network is abnormally disconnected or blocked by firewalls and third-party tools, and cannot provide external services.</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <ol> |
| <li>If it is a rest connection, check whether the requested server configuration is correct.</li> |
| <li>Check whether the network communication is normal, you can use some simple cmd commands to detect, such as <code>ping</code> and so on.</li> |
| </ol> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-2 - Client Timeout</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/2/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/2/</guid><description> |
| <p>Timeout occurs when the caller fails to obtain the corresponding response within the specified time after the request is sent.</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <ol> |
| <li>The server is really slow in processing and cannot return the result within the specified time. The caller will automatically return a timeout exception response to end the call.</li> |
| <li>If the server responds quickly, but when the client load is high and the load pressure is high, it will time out due to problems such as the client request not being sent out or the response stuck in the TCP Buffer. Because the client receives the data sent by the server or requests the data from the server, it will be queued at the system level. If the system load is relatively high, the time spent in the kernel state will increase, causing the client to time out when it gets the value. .</li> |
| <li>Usually the business processing is too slow, and it can be executed on the service provider machine: <code>jstack [PID] &gt; jstack.log</code> to analyze which method calls the threads are stuck on, which is the reason for the slowness. If performance tuning is not an option, increase the timeout threshold.</li> |
| </ol> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <ol> |
| <li>There may be GC on both sides. Check the GC logs of the server and client. A GC that takes a long time will cause a timeout. The occurrence of a timeout probably means that the resource (CPU, memory, or network) of the caller or server has a bottleneck. It is necessary to check whether the problem is on the server or the caller to rule out suspicions such as GC jitter.</li> |
| <li>Check the network quality of the server, such as the retransmission rate to rule out network suspicions.</li> |
| <li>With the help of link tracking analysis services (such as Ali&rsquo;s <a href="https://help.aliyun.com/document_detail/63796.html">ARMS</a>, the open source [OpenTracing](<a href="https://github.com/opentracing/">https://github.com/opentracing/</a> opentracing-java) |
| System implementation <a href="https://github.com/openzipkin/zipkin">Zipkin</a>, <a href="https://github.com/apache/skywalking">SkyWalking</a> etc.) to analyze the time-consuming situation of each point.</li> |
| </ol> |
| <h2 id="acknowledgments">Acknowledgments</h2> |
| <p>The FAQ page of this error code refers to <a href="https://github.com/StabilityMan/StabilityGuide/blob/master/docs/diagnosis/plugin/rpc/%E7%B3%BB%E7%BB%9F%E7%A8%B3%E5%AE%9A%E6%80%A7%E2%80%94%E2%80%94Dubbo%E5%B8%B8%E8%A7%81%E9%94%99%E8%AF%AF%E5%8F%8A%E8%A7%A3%E5%86%B3%E6%96%B9%E6%B3%95.md">&ldquo;Dubbo Common Errors and Solutions&rdquo;</a>.</p> |
| <p>Articles cited are compiled under license <a href="http://creativecommons.org/licenses/by/4.0/">CC-BY-4.0</a>. Thanks to the original author here.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-3 - Failed to close network connection</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/3/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/3/</guid><description> |
| <p>Network connection close failed</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>Non-graceful shutdown of the service. At this time, the server may not complete the external output stream.</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>Generally, it is a prompt warning message, which does not affect subsequent program execution.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-4 - Network communication layer unknown exception</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/4/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/4/</guid><description> |
| <h2 id="reminder">Reminder</h2> |
| <p>The meaning of this error code has been adjusted. If you are looking for information of this error code in Dubbo versions prior than (or equal) 3.1.4 or 3.2.0-beta.3, head to <a href="https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/99/0/">99-0</a>.</p> |
| <p>(This error code is currently absent.)</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-5 - Network disconnection failed</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/5/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/5/</guid><description> |
| <p>Timeout occurs when the caller fails to obtain the corresponding response within the specified time after the request is sent.</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>Client actively disconnects</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>Generally, it is a prompt warning message, which does not affect subsequent program execution.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-6 - Unsupported message</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/6/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/6/</guid><description> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>The returned data is serialized incorrectly, or exceeds the serialization maximum</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>You can use some third-party tools or <code>jstack [PID] &gt; jstack.log</code> to analyze the stack information and locate it.</p> |
| <p>For the specific configuration items and meanings supported by each component, please refer to <a href="https://dubbo.apache.org/en/docs3-v2/java-sdk/reference-manual/config/properties/">Configuration Item Manual</a></p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-7 - Thread Connection Exceeded Warning</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/7/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/7/</guid><description> |
| <p>Reminder message when the number of connections exceeds the limit</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>A warning reminder that the configuration or the number of connections exceeds the configured number.</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>The default configuration item <code>connect.queue.warning.size=1000</code> can be adjusted through configuration.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-8 - Return data decoding failed</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/8/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/8/</guid><description> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>Return data format error or decoding failed</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>Through the debug/warn log mode, the specific service class name and the returned message and stack information can be output.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-9 - There are duplicate serial number IDs</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/9/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/9/</guid><description> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <ol> |
| <li>An empty object is returned.</li> |
| <li>The custom serial number class, <code>org.apache.dubbo.common.serialize.Serialization#getContentTypeId</code> is duplicated with the built-in system, |
| At this time, when loading, the first loaded SPI instance shall prevail. Other items will be skipped.</li> |
| </ol> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <ol> |
| <li>Check the return result.</li> |
| <li>The built-in value can refer to the class <code>org.apache.dubbo.common.serialize.Constants</code></li> |
| </ol> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-10 - Payload Limit Exceeded Exception</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/10/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/10/</guid><description> |
| <p>The default <code>payload=8M</code>, please check the configuration</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>For the specific configuration items and meanings supported by each component, please refer to <a href="https://dubbo.apache.org/en/docs3-v2/java-sdk/reference-manual/config/properties/">Configuration Item Manual</a></p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-11 - Character set not supported</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/11/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/11/</guid><description> |
| <p>Default <code>UTF-8</code> charset</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>The result will end up being processed in the <code>UTF-8</code> character set.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-12 - An error occurred when the ZK client was destroyed</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/12/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/12/</guid><description> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>The connection between the client and the server has been refused |
| When the client is being destroyed, the server may be performing elections or other operations, resulting in an exception.</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>The shutdown method can be used to query stack information. Generally do not deal with.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-13 - Stream closed exception</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/13/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/13/</guid><description> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p><code>Stream is closed</code> or the stream is closed while other threads are reading</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>Generally, the order in which the code closes the streams is reversed.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-14 - Server response failed</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/14/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/14/</guid><description> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>When the server interacts with the client to generate data, the client closes abnormally.</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>The client terminated abnormally or the server crashed.</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-15 - Skip unread stream data</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/15/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/15/</guid><description> |
| <p>When decoding, if there is unread data in the stream, the unread stream will be skipped</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>When decoding, all the data will be read at one time</p> |
| <p style="margin-top: 3rem;"> </p></description></item><item><title>Docs3-V2: 6-16 - An exception occurred during reconnection</title><link>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/16/</link><pubDate>Mon, 01 Jan 0001 00:00:00 +0000</pubDate><guid>https://dubbo.apache.org/en/docs3-v2/java-sdk/faq/6/16/</guid><description> |
| <p>Prompt every time a reconnection occurs</p> |
| <h2 id="possible-reason">Possible Reason</h2> |
| <p>Delayed reconnection caused by network instability.</p> |
| <h2 id="troubleshooting-and-resolution-steps">Troubleshooting and resolution steps</h2> |
| <p>Check for network packet loss.</p> |
| <p style="margin-top: 3rem;"> </p></description></item></channel></rss> |
