Jenkins 添加节点Node报错JNI error has occurred UnsupportedClassVersionError

节点日志 报错信息如下

Error: A JNI error has occurred, please check your installation and try again

Exception in thread "main" java.lang.UnsupportedClassVersionError: hudson/remoting/Launcher has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0

从文字上看第一个错误类型是属于不支持的字节码版本，那就想到当前jenkins默认是用的java 11版本，而目标节点机器上用的java 8，字节码版本不兼容，我试过把这个jenkins的jdk改为11，不行，启动报错，那就只好改目标机器上的java版本了，于是在目标节点机器下载了java 11并把版本选择设置默认为11版本，然后重新laugh Node后节点上线成功。

下载java 11

sudo apt install openjdk-11-jdk --fix-missing

更换java默认版本

 update-alternatives --config java