Elasticsearch的一些api随记

Health

/_cat/health

/_cluster/health

Indices health

/_cat/indices?health=red&v&s=store.size:desc,index

/_cat/indices?health=yellow&v&s=store.size:desc,index

/_cat/indices?health=green&v&s=store.size:desc,index

Nodes

/_cat/nodes?v

Get master node

/_cat/master?v

Cluster allocation explain related

/_cat/shards/index_name-*?v&s=state,index&h=index,shard,prirep,state,docs,store,ip,node,unassigned.reason

/_cluster/allocation/explain

Shards

/_cat/shards

/_cat/shards?index=index_name

Thread pool related

https://www.elastic.co/guide/en/elasticsearch/reference/current/cat-thread-pool.html

/_cluster/settings?pretty&include_defaults=true | grep processors

get maximum number of threads info

curl "127.1:9200/_cat/thread_pool?v&h=ip,node_name,id,name,max,size,queue_size,queue,active,rejected&pretty"

Cluster settings

/_cluster/settings?include_defaults=true&pretty

/_cluster/settings?include_defaults=true

primaries recovery settings

{
    "transient": {
        "cluster": {
            "routing": {
                "allocation": {
                    "node_initial_primaries_recoveries": 10,
                    "node_concurrent_incoming_recoveries": null,
                    "node_concurrent_outgoing_recoveries": null,
                    "node_concurrent_recoveries": 20
                }
            }
        }
    }
}

{
    "transient": {
        "cluster": {
            "routing": {
                "allocation": {
                    "node_initial_primaries_recoveries": null,
                    "node_concurrent_incoming_recoveries": null,
                    "node_concurrent_recoveries": null
                }
            }
        }
    }
}

{
    "persistent": {
        "cluster": {
            "routing": {
                "allocation": {
                    "node_initial_primaries_recoveries": 30,
                    "node_concurrent_incoming_recoveries": null,
                    "node_concurrent_recoveries": 10
                }
            }
        }
    }
}

- new version shard allocation config

cluster.routing.allocation.node_concurrent_recoveries

# es 6.8.2
# PUT /_cluster/settings
{
    "persistent": {
        "cluster": {
            "routing": {
                "allocation": {
                    "node_initial_primaries_recoveries": 8
                }
            }
        }
    }
}
   

Index settings

modify the number of replicas in bulk

{
  "index" : {
    "number_of_replicas" : 1
  }
}
 

get indices and order by number of replicas

/_cat/indices?health=green&v&s=rep:asc,store.size:desc,index

Demo

对于有大量索引的刚重启的es集群

(主分片在1w-2w)

加快es集群恢复速度

结合es节点资源监控图，观测节点cpu压力，以及cpu IO wait

适当通过update cluster settings接口动态增加node_initial_primaries_recoveries (Defaults to 4)

和 node_concurrent_recoveries

(A shortcut to set both cluster.routing.allocation.node_concurrent_incoming_recoveries and cluster.routing.allocation.node_concurrent_outgoing_recoveries

Defaults to 2)数值

通过使用 cluster settings + include_defaults=true 筛选查到当前配置值

减少集群从red状态到yellow状态的耗时：增加索引副本数量，增加node_initial_primaries_recoveries值

减少集群从yellow状态到green状态的耗时：增加 node_concurrent_recoveries 值

通过访问 /_cluster/allocation/explain 接口查到阻碍集群 to green(yellow)的原因

在es集群恢复期间因节点内存压力大(node was low on resources: memory.)而被k8s Evicted

调整缩小 jvm 配置值，尽量不超配(requests 和 limit尽量一致或提高requests值)