could not find java; set JAVA_HOME or ensure java is in PATH
首先需要安裝java
1、yum list installed |grep java 查看當前有沒有裝
有的話先卸載
yum -y remove java-1.8.0-openjdk* *表時卸載所有openjdk相關文件輸入
yum -y remove tzdata-java.noarch 卸載tzdata-java
安裝java
yum install java-1.8.0-openjdk java-1.8.0-openjdk-devel
啟動
sudo -iu www-data /usr/local/elasticsearch/bin/elasticsearch -d #-d為后台啟動
如果還有報錯的話
Exception in thread "main" java.nio.file.AccessDeniedException: /usr/local/elasticsearch/config/jvm.
則要為當前用戶添加權限
chown www-data /usr/local/elasticsearch -R
啟動時，突然服務又停止的話，查看日志
max file descriptors [65535] for elasticsearch process is too low, increase to at least [65536]
解決方法：
1、vi /etc/sysctl.conf
設置fs.file-max=655350
保存之后sysctl -p使設置生效
2、vi /etc/security/limits.conf 新增
* soft nofile 655350
* hard nofile 655350
如報一下錯誤
max number of threads [3820] for user [www-data] is too low, increase to at least [4096]
修改如下:
1、修改配置文件/etc/security/limits.conf
* soft nproc 10240
* hard nproc 10240
* soft nofile 10240
* hard nofile 10240
2、然后重啟即可
其中nofile對應open_files
nproc對應max_user_processes
通過 ulimit -a可以查看max_user_processes
搭建集群時，啟動節點報錯
[node-2] failed to send join request to master [{node-1}{EQwLRT_kSm6sI4KPwsMkKw}{ya57_AoaRaeQbCzJKShWMw}{172.16.100.199}{172.16.100.199:9300}], reason [RemoteTransportException[[node-1][172.16.100.199:9300][internal:discovery/zen/join]]; nested: IllegalArgumentException[can't add node {node-2}{EQwLRT_kSm6sI4KPwsMkKw}{DDv-R-CITnePbZNmPb_1Fw}{172.16.100.201}{172.16.100.201:9300}, found existing node {node-1}{EQwLRT_kSm6sI4KPwsMkKw}{ya57_AoaRaeQbCzJKShWMw}{172.16.100.199}{172.16.100.199:9300} with the same id but is a different node instance]; ]
解決方法如下，節點data文件下的文件清空。