將Linux默認的OpenJDK替換為Oracle JDK - cocowool－IT工程師數位筆記本

文章出處

在使用Logstash安裝插件的時候，發生了一個錯誤，如下：

ERROR: Something went wrong when installing logstash-input-jdbc, message: java.security.KeyException

經查可能是與系統自帶的OpenJDK有關，解決方案是將系統自帶的OpenJDK更新為Oracle的JDK。

[cloud@localhost ~]$ java -version
openjdk version "1.8.0_141"
OpenJDK Runtime Environment (build 1.8.0_141-b16)
OpenJDK 64-Bit Server VM (build 25.141-b16, mixed mode)

下載 Oracle JDK

首先從 Oracle網站下載所需的JDK。

我下載的是 1.8 版本的 rpm 安裝包，因為 Elasticsearch 套裝需要Java 1.8。

安裝Oracle JDK

使用如下命令進行安裝

[root@localhost cloud]# rpm -ivh jdk-8u144-linux-x64.rpm 
Preparing...                          ################################# [100%]
Updating / installing...
   1:jdk1.8.0_144-2000:1.8.0_144-fcs  ################################# [100%]
Unpacking JAR files...
    tools.jar...
    plugin.jar...
    javaws.jar...
    deploy.jar...
    rt.jar...
    jsse.jar...
    charsets.jar...
    localedata.jar...

使用update-alternative配置java

首先執行 update-alternative —list java 看一下系統中有幾個java版本。

[root@localhost cloud]# update-alternatives --display java
java - status is auto.
 link currently points to /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.141-1.b16.el7_3.x86_64/jre/bin/java
/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.51-2.4.5.5.el7.x86_64/jre/bin/java - priority 170051
 slave ControlPanel: (null)
 slave javaws: (null)
 slave jcontrol: (null)
 slave jjs: (null)
/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.141-1.b16.el7_3.x86_64/jre/bin/java - family java-1.8.0-openjdk.x86_64 priority 1800141
 slave ControlPanel: (null)
 slave javaws: (null)
 slave jcontrol: (null)
 slave jjs: /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.141-1.b16.el7_3.x86_64/jre/bin/jjs
/usr/java/jdk1.8.0_144/jre/bin/java - priority 180144
 slave ControlPanel: /usr/java/jdk1.8.0_144/jre/bin/ControlPanel
 slave javaws: /usr/java/jdk1.8.0_144/jre/bin/javaws
 slave jcontrol: /usr/java/jdk1.8.0_144/jre/bin/jcontrol
 slave jjs: /usr/java/jdk1.8.0_144/jre/bin/jjs
Current `best' version is /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.141-1.b16.el7_3.x86_64/jre/bin/java.

輸出的內容省略了一部分，可以看到，系統中存在OpenJDK 和 Oracle的JDK，下面選擇Oracle JDK為默認

[root@localhost cloud]# update-alternatives --config java

There are 3 programs which provide 'java'.

  Selection    Command
-----------------------------------------------
   1           /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.51-2.4.5.5.el7.x86_64/jre/bin/java
*+ 2           java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.141-1.b16.el7_3.x86_64/jre/bin/java)
   3           /usr/java/jdk1.8.0_144/jre/bin/java

Enter to keep the current selection[+], or type selection number: 3
[root@localhost cloud]# java -version
java version "1.8.0_144"
Java(TM) SE Runtime Environment (build 1.8.0_144-b01)
Java HotSpot(TM) 64-Bit Server VM (build 25.144-b01, mixed mode)