两个elasticsearch节点只保留一个(移除节点）

GET _cat/nodes?v
GET _cluster/health?pretty
现在有两个节点node1/node2

1.副本数设置为0

PUT _all/_settings
{
  "index.number_of_replicas": 0
}

2.排除不需要的节点

PUT _cluster/settings
{
  "persistent": {
    "cluster.routing.allocation.exclude._name": "node2"
  }
}

3. 监控迁移进度（可反复执行，直到完成）

确认 niewj2 不再出现在结果里，或者它对应的分片 state 都是 STARTED 且 node 已经变成 niewj
GET _cat/shards?v&h=index,shard,prirep,state,node

index                                                              shard prirep state   node
kibana_sample_data_flights-new                                     0     p      STARTED node1
recruit_wutong_application_index                                   0     p      STARTED node1
.ds-.logs-deprecation.elasticsearch-default-2025.09.24-000007      0     p      STARTED node1
.ds-kibana_sample_data_logs-2025.02.25-000001                      0     p      STARTED node1
kibana_sample_data_ecommerce                                       0     p      STARTED node1
.internal.alerts-ml.anomaly-detection-health.alerts-default-000001 0     p      STARTED node1
movies                                                             0     p      STARTED node1
books                                                              0     p      STARTED node1
.kibana-observability-ai-assistant-conversations-000001            0     p      STARTED node1
my_index                                                           0     p      STARTED node1
.ds-.kibana-event-log-ds-2025.03.01-000002                         0     p      STARTED node1
.internal.alerts-observability.logs.alerts-default-000001          0     p      STARTED node1
.async-search                                                      0     p      STARTED node1
movies-new                                                         0     p      STARTED node1

4.查看集群状态

GET _cluster/health

{
  "cluster_name": "clusternie",
  "status": "green",
  "timed_out": false,
  "number_of_nodes": 2,
  "number_of_data_nodes": 2,
  "active_primary_shards": 57,
  "active_shards": 57,
  "relocating_shards": 0,
  "initializing_shards": 0,
  "unassigned_shards": 0,
  "delayed_unassigned_shards": 0,
  "number_of_pending_tasks": 0,
  "number_of_in_flight_fetch": 0,
  "task_max_waiting_in_queue_millis": 0,
  "active_shards_percent_as_number": 100
}

5. 停止并禁用 node2 服务（需要在服务器终端执行）

sudo systemctl stop es2.service
sudo systemctl disable es2.service

6.修改node1的配置文件elasticsearch.yml

discovery.seed_hosts: ["127.0.0.1:9300"]   # 只保留 node1 的 transport 端口
cluster.initial_master_nodes: ["node1"]   # 只保留 node1

7. 重启node1

sudo systemctl restart elasticsearch

8.最后确认单节点 Green 状态

GET _cluster/health

"status" : "green"，"number_of_nodes" : 1