在之前 ElasticSearch 搭建好之后，我们通过 elasticsearch-header 插件在查看 ES 服务的时候，发现 cluster-health 显示的是 YELLOW。
Why？ 首先，我们需要知道的是：颜色代表集群的健康状态。现在的颜色状态有：
* RED(红): 代表具体的分片还没有在集群中分配好； * YELLOW(黄): 代表主分片已经分配好，但是副本尚未分配； * GREEN(绿)：表示所有的分片都已分配好，群集正常运行；有了以上的简介之后，笔者觉得，单节点导致显示的 YELLOW 还可以完善，所以开始搭建 ** ES Cluster **。 首先，我们需要更新之前的配置。进入之前的解压目录，打开配置文件：
vim elasticsearch.yml我们需要更新这样几个参数：
node.name： 指定当前节点的名称。我现在有两台机子，可以设置两个节点，所以，这里一个起名为 master，一个为 node1;node.master: 指定主节点。值一个设置为 true，另一个为 false；discovery.zen.ping.unicast.hosts：这里设置的是节点的 ip，或者自己配置 hosts 文件，指定 ip映射关系，直接写ip对应的名称；discovery.zen.minimum_master_nodes：这里，我的主节点是1个，所以我在这配置的是 1；具体的可以参考discovery.zen.minimum_master_nodes在主节点配置好后，通过 scp 传输到 node1 节点上面，参数也做相应的改变即可。比如 node.name 更新成 node1， node.master: false。其他的保持一致。 我目前的主节点配置如下：
# ======================== Elasticsearch Configuration ========================= # # NOTE: Elasticsearch comes with reasonable defaults for most settings. # Before you set out to tweak and tune the configuration, make sure you # understand what are you trying to accomplish and the consequences. # # The primary way of configuring a node is via this file. This template lists # the most important settings you may want to configure for a production cluster. # # Please consult the documentation for further information on configuration options: # https://www.elastic.co/guide/en/elasticsearch/reference/index.html # # ---------------------------------- Cluster ----------------------------------- # # Use a descriptive name for your cluster: # #cluster.name: my-application cluster.name: es-demo # # ------------------------------------ Node ------------------------------------ # # Use a descriptive name for the node: # #node.name: node-1 node.name: master node.master: true # # Add custom attributes to the node: # #node.attr.rack: r1 node.attr.rack: r1 # # ----------------------------------- Paths ------------------------------------ # # Path to directory where to store the data (separate multiple locations by comma): # #path.data: /path/to/data path.data: /data/elasticsearch # # Path to log files: # #path.logs: /path/to/logs path.logs: /data/logs/elasticsearch # # ----------------------------------- Memory ----------------------------------- # # Lock the memory on startup: # # bootstrap.memory_lock: true # # Make sure that the heap size is set to about half the memory available # on the system and that the owner of the process is allowed to use this # limit. # # Elasticsearch performs poorly when the system is swapping the memory. # # ---------------------------------- Network ----------------------------------- # # Set the bind address to a specific IP (IPv4 or IPv6): # network.host: 192.168.1.58 # 从节点成对应的 ip # # Set a custom port for HTTP: # http.port: 9200 # # For more information, consult the network module documentation. # # --------------------------------- Discovery ---------------------------------- # # Pass an initial list of hosts to perform discovery when new node is started: # The default list of hosts is ["127.0.0.1", "[::1]"] # discovery.zen.ping.unicast.hosts: ["192.168.1.58", "192.168.1.54"] # # Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1): # discovery.zen.minimum_master_nodes: 1 # # For more information, consult the zen discovery module documentation. # # ---------------------------------- Gateway ----------------------------------- # # Block initial recovery after a full cluster restart until N nodes are started: # #gateway.recover_after_nodes: 3 # # For more information, consult the gateway module documentation. # # ---------------------------------- Various ----------------------------------- # # Require explicit names when deleting indices: # #action.destructive_requires_name: true # --------------------------------- 其他配置 ----------------------------------- http.cors.enabled: true http.cors.allow-origin: "*"更新好配置之后呢，我们开始启动 ElasticSearch 服务。我启动 master 和 node1，发现出现了下面的错误：
max virtual memory areas vm.max_map_count [65530] likely too low, increase to at least [262144]查询发现，导致这种错误，是因为系统默认的 max_map_count 过低所致，我们需要设置大一点（按报错直接翻译也可知哦^(^）。我们需要设置一下这个参数：
sudo vim /etc/sysctl.conf在最末尾添加：
vm.max_map_count=262144两台机子配置好之后，我们重新启动下 elasticsearch。这时候 log 也已经提示了：
Cluster health status changed from [YELLOW] to [GREEN] (reason: [shards started [[movies][0]] ...])好了。刷新下 elasticsearch-head，发现如下图所示：
至此，集群环境算是配置好了，集群状态也从 YELLOW 转到 GREEN 了。 原文网址 http://www.cnblogs.com/scharfsinnig/p/6759630.html
参考：
discovery.zen.minimum_master_nodes 参数说明vm_map_count 设置
转载于:https://www.cnblogs.com/scharfsinnig/p/6759630.html
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