linux tomcat启动时卡在“INFO: Deploying web application directory ......”的解决方案

淩亂°似流年 2022-05-15 08:36 213阅读 0赞

原文：[https://blog.csdn.net/njchenyi/article/details/46641141][https_blog.csdn.net_njchenyi_article_details_46641141]

解决办法：  
  
  
永久：修改 $JAVA\_HOME/jre/lib/security/java.security 文件，替换securerandom.source=file:/dev/random 为 securerandom.source=file:/dev/urandom。对所有使用JVM的应用生效。（**vim $JAVA\_HOME/jre/lib/security/java.security**）  
  
  
DOMAIN临时：修改startWeblogic.sh文件，JAVA\_OPTIONS="$\{SAVE\_JAVA\_OPTIONS\} -Djava.security.egd=file:/dev/./urandom"

详细说明：

linux或者部分unix系统提供随机数设备是/dev/random 和/dev/urandom ，两个有区别，urandom安全性没有random高，但random需要时间间隔生成随机数。jdk默认调用random。  
  
  
再后来，终于在weblogic的官方文档中 Monitoring and Troubleshooting 找到了 Avoiding JVM Delays Caused By Random Number Generation 这样一个标题。摘录如下：  
  
The library used for random number generation in Sun's JVM relies on /dev/random by default for UNIX platforms. This can potentially block the Oracle WebLogic Communication Services process because on some operating systems /dev/random waits for a certain amount of "noise" to be generated on the host machine before returning a result. Although /dev/random is more secure, Oracle recommends using /dev/urandom if the default JVM configuration delays Oracle WebLogic Communication Services startup.  
  
To determine if your operating system exhibits this behavior, try displaying a portion of the file from a shell prompt:  
  
head -n 1 /dev/random  
Open the $JAVA\_HOME/jre/lib/security/java.security file in a text editor.  
  
Change the line:  
  
securerandom.source=file:/dev/random  
to read:  
  
securerandom.source=file:/dev/urandom  
Save your change and exit the text editor.  
其中说到：可通过 head -n 1 /devrandom 查看是否你的系统会出现伪随机数提供等待。OK就这个，试了一下，果然，在服务器第一次启动后，这个可以快速提供一个值，但当再次调用时发生等待。

[https_blog.csdn.net_njchenyi_article_details_46641141]: https://blog.csdn.net/njchenyi/article/details/46641141