elasticsearch安装

官网：https://www.elastic.co/downloads/elasticsearch

方式一rpm 安装

#下载elasticsearch
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.5.3.rpm
#安装
cp elasticsearch-6.5.3.rpm /usr/elasticsearch
rpm -ivh elasticsearch-6.5.3.rpm
开启Elasticsearch服务 
service elasticsearch start

测试

[root@iZ2ze9d7x8qidhuch2m2mjZ elasticsearch]# curl -XGET 'http://localhost:9200'
{
  "name" : "rAzftpt",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "6PTp3WYiQA6pawdx-vh87w",
  "version" : {
    "number" : "6.5.3",
    "build_flavor" : "default",
    "build_type" : "rpm",
    "build_hash" : "159a78a",
    "build_date" : "2018-12-06T20:11:28.826501Z",
    "build_snapshot" : false,
    "lucene_version" : "7.5.0",
    "minimum_wire_compatibility_version" : "5.6.0",
    "minimum_index_compatibility_version" : "5.0.0"
  },
  "tagline" : "You Know, for Search"
}

方式二 压缩包

es官方提供多种方式下载途径，我这里推荐使用zip/tar.gz方式来下载安装，因为zip和tar.gz适用于任何操作系统，以下是基于Linux系统的案例。

#下载es
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.1.2.tar.gz
 #wget https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/tar/elasticsearch/2.4.0/elasticsearch-2.4.0.tar.gz

#解压

tar -xzf elasticsearch-6.1.2.tar.gz

启动
es很方便，解压就可以直接用了，下面我们尝试运行一下。

[root@localhost elasticsearch-6.1.2]# ./bin/elasticsearch
[2018-01-28T22:00:31,358][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: java.lang.RuntimeException: can not run elasticsearch as root
	at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:125) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:112) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-6.1.2.jar:6.1.2]
	at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-6.1.2.jar:6.1.2]
	at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:92) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:85) ~[elasticsearch-6.1.2.jar:6.1.2]
Caused by: java.lang.RuntimeException: can not run elasticsearch as root
	at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:104) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:171) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:322) ~[elasticsearch-6.1.2.jar:6.1.2]
	at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:121) ~[elasticsearch-6.1.2.jar:6.1.2]
	... 6 more

很不幸，启动报错了 can not run elasticsearch as root，看起来root不允许直接启动。因为这个原因，那我们需要新建一个用户来启动es，具体操作如下：

# 以root用户来创建新的用户 ， groupadd 添加一个用户组
[root@localhost home]# groupadd elasticsearch 
# 添加一个用户，-g是在用户组下 -p是密码
[root@localhost home]# useradd elasticsearch -g elasticsearch -p elasticsearch
# 进入es的安装目录
[root@localhost home]# cd /home/elasticsearch 
# 给用户elasticsearch 授权
[root@localhost home]# chown -R elasticsearch:elasticsearch elasticsearch-6.1.2/
# 切换到 elasticsearch 用户
[root@localhost elasticsearch]# su elasticsearch

到这里新的用户也创建好了，也授权了，接下来我们重新启动一下

[elasticsearch@localhost elasticsearch-6.1.2]$ ./bin/elasticsearch
[2018-01-28T22:11:06,918][INFO ][o.e.n.Node               ] [] initializing ...
[2018-01-28T22:11:07,161][INFO ][o.e.e.NodeEnvironment    ] [qR5cyzh] using [1] data paths, mounts [[/ (rootfs)]], net usable_space [12.5gb], net total_space [17.6gb], types [rootfs]
[2018-01-28T22:11:07,162][INFO ][o.e.e.NodeEnvironment    ] [qR5cyzh] heap size [1015.6mb], compressed ordinary object pointers [true]
[2018-01-28T22:11:07,163][INFO ][o.e.n.Node               ] node name [qR5cyzh] derived from node ID [qR5cyzhRQUix7PbCNFViTw]; set [node.name] to override
[2018-01-28T22:11:07,163][INFO ][o.e.n.Node               ] version[6.1.2], pid[7200], build[5b1fea5/2018-01-10T02:35:59.208Z], OS[Linux/3.10.0-514.el7.x86_64/amd64], JVM[Oracle Corporation/Java HotSpot(TM) 64-Bit Server VM/1.8.0_141/25.141-b15]
[2018-01-28T22:11:07,163][INFO ][o.e.n.Node               ] JVM arguments [-Xms1g, -Xmx1g, -XX:+UseConcMarkSweepGC, -XX:CMSInitiatingOccupancyFraction=75, -XX:+UseCMSInitiatingOccupancyOnly, -XX:+AlwaysPreTouch, -Xss1m, -Djava.awt.headless=true, -Dfile.encoding=UTF-8, -Djna.nosys=true, -XX:-OmitStackTraceInFastThrow, -Dio.netty.noUnsafe=true, -Dio.netty.noKeySetOptimization=true, -Dio.netty.recycler.maxCapacityPerThread=0, -Dlog4j.shutdownHookEnabled=false, -Dlog4j2.disable.jmx=true, -XX:+HeapDumpOnOutOfMemoryError, -Des.path.home=/home/elasticsearch/elasticsearch-6.1.2, -Des.path.conf=/home/elasticsearch/elasticsearch-6.1.2/config]
[2018-01-28T22:11:09,295][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [aggs-matrix-stats]
[2018-01-28T22:11:09,295][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [analysis-common]
[2018-01-28T22:11:09,295][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [ingest-common]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [lang-expression]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [lang-mustache]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [lang-painless]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [mapper-extras]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [parent-join]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [percolator]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [reindex]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [repository-url]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [transport-netty4]
[2018-01-28T22:11:09,296][INFO ][o.e.p.PluginsService     ] [qR5cyzh] loaded module [tribe]
[2018-01-28T22:11:09,297][INFO ][o.e.p.PluginsService     ] [qR5cyzh] no plugins loaded
[2018-01-28T22:11:13,791][INFO ][o.e.d.DiscoveryModule    ] [qR5cyzh] using discovery type [zen]
[2018-01-28T22:11:14,926][INFO ][o.e.n.Node               ] initialized
[2018-01-28T22:11:14,927][INFO ][o.e.n.Node               ] [qR5cyzh] starting ...
[2018-01-28T22:11:15,582][INFO ][o.e.t.TransportService   ] [qR5cyzh] publish_address {127.0.0.1:9300}, bound_addresses {[::1]:9300}, {127.0.0.1:9300}
[2018-01-28T22:11:15,598][WARN ][o.e.b.BootstrapChecks    ] [qR5cyzh] max file descriptors [4096] for elasticsearch process is too low, increase to at least [65536]
[2018-01-28T22:11:15,598][WARN ][o.e.b.BootstrapChecks    ] [qR5cyzh] max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
[2018-01-28T22:11:18,915][INFO ][o.e.c.s.MasterService    ] [qR5cyzh] zen-disco-elected-as-master ([0] nodes joined), reason: new_master {qR5cyzh}{qR5cyzhRQUix7PbCNFViTw}{wRzc-CVaRmmdLNnPfT_LTA}{127.0.0.1}{127.0.0.1:9300}
[2018-01-28T22:11:18,920][INFO ][o.e.c.s.ClusterApplierService] [qR5cyzh] new_master {qR5cyzh}{qR5cyzhRQUix7PbCNFViTw}{wRzc-CVaRmmdLNnPfT_LTA}{127.0.0.1}{127.0.0.1:9300}, reason: apply cluster state (from master [master {qR5cyzh}{qR5cyzhRQUix7PbCNFViTw}{wRzc-CVaRmmdLNnPfT_LTA}{127.0.0.1}{127.0.0.1:9300} committed version [1] source [zen-disco-elected-as-master ([0] nodes joined)]])
[2018-01-28T22:11:19,028][INFO ][o.e.g.GatewayService     ] [qR5cyzh] recovered [0] indices into cluster_state
[2018-01-28T22:11:19,097][INFO ][o.e.h.n.Netty4HttpServerTransport] [qR5cyzh] publish_address {127.0.0.1:9200}, bound_addresses {[::1]:9200}, {127.0.0.1:9200}
[2018-01-28T22:11:19,097][INFO ][o.e.n.Node               ] [qR5cyzh] started

很顺利，启动成功了，我们curl来试一下

[yun@localhost ~]$ curl "127.0.0.1:9200"
{
  "name" : "qR5cyzh",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "I52THkAwTU-oB8GQs_7jhQ",
  "version" : {
    "number" : "6.1.2",
    "build_hash" : "5b1fea5",
    "build_date" : "2018-01-10T02:35:59.208Z",
    "build_snapshot" : false,
    "lucene_version" : "7.1.0",
    "minimum_wire_compatibility_version" : "5.6.0",
    "minimum_index_compatibility_version" : "5.0.0"
  },
  "tagline" : "You Know, for Search"
}

默认情况下，Elastic 只允许本机访问，如果需要远程访问，可以修改 Elastic 安装目录的config/elasticsearch.yml文件，去掉network.host的注释，将它的值改成0.0.0.0，然后重新启动 Elastic。

network.host: 0.0.0.0

常用指令

service elasticsearch start
service elasticsearch stop
service elasticsearch restart
service elasticsearch status

配置

elasticsearch 中的JVM配置文件

-Xms2g
-Xmx2g

① 将最小堆大小（Xms）和最大堆大小（Xmx）设置为彼此相等。
② Elasticsearch可用的堆越多，可用于缓存的内存就越多。但请注意，太多的堆可能会使您长时间垃圾收集暂停。
③ 设置Xmx为不超过物理RAM的50％，以确保有足够的物理内存留给内核文件系统缓存。
④ 不要设置Xmx为JVM用于压缩对象指针的临界值以上；确切的截止值有所不同，但接近32 GB。不要超过32G，如果空间大，多跑几个实例，不要让一个实例太大内存

** 参考文章**

• https://my.oschina.net/codingcloud/blog/1615013
• http://www.cnblogs.com/along21/p/8613115.html