Elasticsearch的功能，主要用在搜索领域，这里，我来研究这个，也是项目需要，为公司开发了一款CMS系统，网站上的搜索栏功能，我打算采用Elasticsearch来实现。 Elasticsearch的高性能，低延时是最大的吸引力。
系统环境：
CentOS6.8， X86_64。
Elasticsearch的版本： 2.3.5，下载地址来自官网，选择的是RPM包。
es安装完毕后，默认安装的路径是/usr/share/elasticsearch, 配置文件，默认是在/etc/elasticsearch目录。这里要重点说说配置文件的信息：
1 [root@CloudGame bin]# cd /etc/elasticsearch/ 2 [root@CloudGame elasticsearch]# ll 3 total 12 4 -rwxr-x---. 1 root elasticsearch 3189 Jul 27 18:34 elasticsearch.yml 5 -rwxr-x---. 1 root elasticsearch 2571 Jul 27 18:34 logging.yml 6 drwxr-x---. 2 root elasticsearch 4096 Jul 27 18:44 scripts 7 [root@CloudGame elasticsearch]# tree 8 . 9 ├── elasticsearch.yml #es的系统配置文件 10 ├── logging.yml #es的日志配置文件 11 └── scripts 12 13 1 directory, 2 files
单实例的启动很简单，安装完成后，直接service elasticsearch start即可启动，日志在/var/log/elasticsearch目录，数据在/var/lib/elasticsearch目录。
这里重点放在如何配置单机多实例上面。为了简单起见，多实例就选择启动2个实例，更多的实例，和2个实例是一样的配置，只是简单的相应改改参数即可。
1. 在/etc目录下创建esconf目录，然后在esconf下面创建esins1以及esins2目录。将原本/etc/elasticsearch目录的内容copy到esins1以及esins2目录下。
1 [root@CloudGame esconf]# pwd 2 /etc/esconf 3 [root@CloudGame esconf]# tree 4 . 5 ├── esins1 6 │ ├── elasticsearch.yml 7 │ ├── logging.yml 8 │ └── scripts 9 ├── esins2 10 ├── elasticsearch.yml 11 ├── logging.yml 12 └── scripts 13 14 15 4 directories, 6 files
2. 修改配置文件elasticsearch.yml,对esins1以及esins2下面的这个文件都做修改。主要是修改其节点信息，网络链接信息，以及日志数据路径信息。下面直接上修改好的配置文件内容。
实例1： esins1目录下的elasticsearch.yml内容
1 [root@CloudGame esins1]# cat elasticsearch.yml 2 # ======================== Elasticsearch Configuration ========================= 3 # 4 # NOTE: Elasticsearch comes with reasonable defaults for most settings. 5 # Before you set out to tweak and tune the configuration, make sure you 6 # understand what are you trying to accomplish and the consequences. 7 # 8 # The primary way of configuring a node is via this file. This template lists 9 # the most important settings you may want to configure for a production cluster. 10 # 11 # Please see the documentation for further information on configuration options: 12 # <http://> 13 # 14 # ---------------------------------- Cluster ----------------------------------- 15 # 16 # Use a descriptive name for your cluster: 17 # 18 cluster.name: tksearch #es默认的集群名称是elasticsearch，注意，集群中是以name来区分节点属于那个集群的。 19 # 20 # ------------------------------------ Node ------------------------------------ 21 # 22 # Use a descriptive name for the node: 23 # 24 node.name: node1 #节点的名称 25 # 26 # Add custom attributes to the node: 27 # 28 # node.rack: r1 29 # 30 node.master: true #是否让这个节点作为默认的master，若不是，默认会选择集群里面的第一个作为master，es有一套选择那个节点作为master的机制 31 # ----------------------------------- Paths ------------------------------------ 32 # 33 # Path to directory where to store the data (separate multiple locations by comma): 34 # 35 path.data: /home/AppData/es/esins1/data #配置节点数据存放的目录 36 # 37 # Path to log files: 38 # 39 path.logs: /home/AppData/es/esins1/logs #配置节点日志存放的目录 40 # 41 # ----------------------------------- Memory ----------------------------------- 42 # 43 # Lock the memory on startup: 44 # 45 # bootstrap.mlockall: true 46 # 47 # Make sure that the `ES_HEAP_SIZE` environment variable is set to about half the memory 48 # available on the system and that the owner of the process is allowed to use this limit. 49 # 50 # Elasticsearch performs poorly when the system is swapping the memory. 51 # 52 # ---------------------------------- Network ----------------------------------- 53 # 54 # Set the bind address to a specific IP (IPv4 or IPv6): 55 # 56 network.host: 0.0.0.0 #配置节点绑定的地址，全0表示可以绑定任何地址，当然这里，本机可以是127.0.0.1回还地址，也可以是ifconfig看到的eth1的地址。 57 # 58 # Set a custom port for HTTP: 59 # 60 http.port: 9200 #配置当前节点对外http访问的端口号，默认是9200，不配的话，es会从9200-9299当中找一个未用过的。 61 # 62 # For more information, see the documentation at: 63 # <http://> 64 # 65 transport.tcp.port: 9300 #es集群节点之间的通信端口号。默认9300. 66 # --------------------------------- Discovery ---------------------------------- 67 # 68 # Pass an initial list of hosts to perform discovery when new node is started: 69 # The default list of hosts is ["127.0.0.1", "[::1]"] 70 # 71 discovery.zen.ping.unicast.hosts: ["127.0.0.1:9300"] #集群多播时发现其他节点的主机列表， 真实多机集群环境下，这里会是多个主机的IP列表，默认格式“host：port”的数组 72 # 73 # Prevent the "split brain" by configuring the majority of nodes (total number of nodes / 2 + 1): 74 # 75 # discovery.zen.minimum_master_nodes: 3 76 # 77 # For more information, see the documentation at: 78 # <http://> 79 # 80 # ---------------------------------- Gateway ----------------------------------- 81 # 82 # Block initial recovery after a full cluster restart until N nodes are started: 83 # 84 # gateway.recover_after_nodes: 3 85 # 86 # For more information, see the documentation at: 87 # <http://> 88 # 89 # ---------------------------------- Various ----------------------------------- 90 # 91 # Disable starting multiple nodes on a single system: 92 # 93 node.max_local_storage_nodes: 2 #默认情况下，是不建议单机启动多个node的，这里这个参数，就是告知es单机上启动了几个实例，这里我们配置2个，若是要配置3个或者更多实例，修改这个数字即可 94 # 95 # Require explicit names when deleting indices: 96 # 97 # action.destructive_requires_name: true
实例2： esins2目录下的elasticsearch.yml内容，配置和esins1几乎一样。