下載內容
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.6.2-linux-x86_64.tar.gz
安裝最新版es報錯
報錯內容如下：
01 解析地址錯誤centos8
wget: 無法解析主機地址 “artifacts.elastic.co
解決辦法,添加解析的，修改resolv.conf
[root@localhost etc]# cat resolv.conf
# Generated by NetworkManager
[root@localhost etc]# vi resolv.conf
# Generated by NetworkManager
nameserver 8.8.8.8
nameserver 8.8.4.4
02 權限報錯，不能使用root用戶
org.elasticsearch.bootstrap.StartupException: java.lang.RuntimeException: can not run elasticsearch as root
創建用戶，賦權限，並切換用戶
[root@localhost bin]# useradd es
[root@localhost bin]# passwd es
授權
[root@localhost bin]# chmod -R 777 /usr/local/apps/elasticsearch-7.6.2
輸入自己的密碼，切換用戶
[root@localhost bin]# su es
啓動報錯，權限問題（jdk版本，問題可以看要求的jdk版本：https://www.elastic.co/cn/support/matrix#matrix_jvm ）product and jvm 說明部分
[es@localhost bin]$ ./elasticsearch
future versions of Elasticsearch will require Java 11; your Java version from [/usr/local/apps/jdk1.8.0_231/jre] does not meet this requirement
Exception in thread "main" java.nio.file.AccessDeniedException: /usr/local/apps/elasticsearch-7.6.2/config/jvm.options
xpack.ml.enabled: false 未設置【報錯內容告訴你了】
[2020-04-03T11:46:40,903][ERROR][o.e.b.ElasticsearchUncaughtExceptionHandler] [localhost.localdomain] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: ElasticsearchException[Failure running machine learning native code. This could be due to running on an unsupported OS or distribution, missing OS libraries, or a problem with the temp directory. To bypass this problem by running Elasticsearch without machine learning functionality set [xpack.ml.enabled: false].]
編輯config 下的文件
[es@localhost bin]$ cd ../config
[es@localhost config]$ vi elasticsearch.yml
xpack.ml.enabled: false
順便修改一下端口，網絡主機，服務發現地址，服務名稱什麼的
http.port: 9200
network.host: 192.168.23.13
discovery.seed_hosts: ["192.168.23.13"]
cluster.name: es_search
如果沒注意，把空格去掉了就會報錯 cluster.name:es_search 【報錯】 cluster.name: es_search 【正確】
意思是說沒找到value (空格bug哈)
SettingsException[Failed to load settings from [elasticsearch.yml]]; nested: ParsingException[Failed to parse object: expecting token of type [START_OBJECT] but found [VALUE_STRING]];
沒完，接着報錯，按照推薦的數據修改配置文件
[2020-04-03T12:11:53,705][INFO ][o.e.b.BootstrapChecks ] [localhost.localdomain] bound or publishing to a non-loopback address, enforcing bootstrap checks
ERROR: [3] bootstrap checks failed
[1]: max file descriptors [4096] for elasticsearch process is too low, increase to at least [65535]
[2]: max number of threads [3069] for user [es] is too low, increase to at least [4096]
[3]: max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
參考博文：https://www.cnblogs.com/zhi-leaf/p/8484337.html
切回到root用戶
[es@localhost bin]$ su root
修改配置文件（/etc/security/limits.conf 和 /etc/sysctl.conf）
添加limits.conf【是有星號的】
[root@localhost bin]# vi /etc/security/limits.conf
* soft nofile 65536
* hard nofile 65536
* soft nproc 4096
* hard nproc 4096
[root@localhost bin]# vi /etc/sysctl.conf
vm.max_map_count=262144
生效
[root@localhost bin]# sysctl -p
切回新增加的用戶啓動
[root@localhost bin]# su es
[es@localhost bin]$ ./elasticsearch
訪問是否成功
集羣版修改一下 discovery.seed_hosts，列出其他虛擬機上的ip地址
discovery.seed_hosts: ["192.168.23.12","192.168.23.13","192.168.23.14"]
#discovery.seed_hosts: ["192.168.23.12"]