elasticsearch _cat命令详解 （秒懂+史上最全）
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ES-cat相关命令汇总
_cat/allocation #查看单节点的shard分配整体情况
_cat/shards #查看各shard的详细情况
_cat/shards/{index} #查看指定分片的详细情况
_cat/master #查看master节点信息
_cat/nodes #查看所有节点信息
_cat/indices #查看集群中所有index的详细信息
_cat/indices/{index} #查看集群中指定index的详细信息
_cat/segments #查看各index的segment详细信息,包括segment名, 所属shard, 内存(磁盘)占用大小, 是否刷盘
_cat/segments/{index}#查看指定index的segment详细信息
_cat/count #查看当前集群的doc数量
_cat/count/{index} #查看指定索引的doc数量
_cat/recovery #查看集群内每个shard的recovery过程.调整replica。
_cat/recovery/{index}#查看指定索引shard的recovery过程
_cat/health #查看集群当前状态：红、黄、绿
_cat/pending_tasks #查看当前集群的pending task
_cat/aliases #查看集群中所有alias信息,路由配置等
_cat/aliases/{alias} #查看指定索引的alias信息
_cat/thread_pool #查看集群各节点内部不同类型的threadpool的统计信息,
_cat/plugins #查看集群各个节点上的plugin信息
_cat/fielddata #查看当前集群各个节点的fielddata内存使用情况
_cat/fielddata/{fields} #查看指定field的内存使用情况,里面传field属性对应的值
_cat/nodeattrs #查看单节点的自定义属性
_cat/repositories #输出集群中注册快照存储库
_cat/templates #输出当前正在存在的模板信息
Cat 命令公共参数
- Help 查看帮助
GET _cat/master?help
id | | node id
host | h | host name
ip | | ip address
node | n | node name
- Verbose 显示列名
GET _cat/master?v
id host ip node
AhlyPtZYTta1AVH_7mUSbQ node1 192.168.113.101 master-1
- Headers 只显示特定列
GET _cat/master?v&h=host,ip,node
host ip node
node1 192.168.113.101 master-1
- 数字格式化
bytes=kb store.size以kb输出
GET _cat/indices?v&h=index,docs.count,store.size&bytes=kb
index docs.count store.size
.monitoring-es-6-2018.08.25 441 721
.monitoring-kibana-6-2018.08.25 18 205
.kibana 1 7
.security-6 3 19
- Format 输出格式
##支持的输出格式有json,test,yaml等
##默认以text格式输出
##以json格式输出 format=json&pretty
GET _cat/indices?v&h=index,docs.count,store.size&bytes=kb&format=json&pretty
[
{
"index": ".monitoring-es-6-2018.08.25",
"docs.count": "476",
"store.size": "1114"
},
{
"index": ".monitoring-kibana-6-2018.08.25",
"docs.count": "21",
"store.size": "72"
},
{
"index": ".kibana",
"docs.count": "1",
"store.size": "7"
},
{
"index": ".security-6",
"docs.count": "3",
"store.size": "19"
}
]
##以yaml格式输出 format=yaml&pretty
GET _cat/indices?v&h=index,docs.count,store.size&bytes=kb&format=yaml&pretty
---
- index: ".monitoring-es-6-2018.08.25"
docs.count: "509"
store.size: "979"
- index: ".monitoring-kibana-6-2018.08.25"
docs.count: "24"
store.size: "142"
- index: ".kibana"
docs.count: "1"
store.size: "7"
- index: ".security-6"
docs.count: "3"
store.size: "19"
- Sort 排序
##按index升序，docs.count降序
GET _cat/indices?v&h=index,docs.count,store.size&bytes=kb&format=json&pretty&s=index,docs.count:desc
[
{
"index": ".kibana",
"docs.count": "1",
"store.size": "7"
},
{
"index": ".monitoring-es-6-2018.08.25",
"docs.count": "608",
"store.size": "1068"
},
{
"index": ".monitoring-kibana-6-2018.08.25",
"docs.count": "33",
"store.size": "163"
},
{
"index": ".security-6",
"docs.count": "3",
"store.size": "19"
}
]
查看集群健康状态
GET _cat/health?v&h=cluster,status
cluster status
my-elk green
查看集群节点和磁盘剩余
##集群节点
GET _cat/nodes?v
ip heap.percent ram.percent cpu load_1m load_5m load_15m node.role master name
192.168.113.103 60 93 5 0.54 0.53 0.55 di - data-2
192.168.113.104 12 87 7 0.72 0.77 0.94 - - client-1
192.168.113.101 13 90 4 0.35 0.32 0.37 m * master-1
192.168.113.102 46 91 100 2.81 2.84 3.44 di - data-1
##磁盘剩余
GET _cat/nodes?v&h=ip,node.role,name,disk.avail
ip node.role name disk.avail
192.168.113.102 di data-1 2.4gb
192.168.113.103 di data-2 6.5gb
192.168.113.104 - client-1 5gb
192.168.113.101 m master-1 6.5gb
查看集群master节点
GET _cat/master?v
id host ip node
AhlyPtZYTta1AVH_7mUSbQ node1 192.168.113.101 master-1
查看分配
##查看每个数据节点上的分片数(shards)，以及每个数据节点磁盘剩余
GET _cat/allocation?v
shards disk.indices disk.used disk.avail disk.total disk.percent host ip node
4 8.2mb 14gb 3.2gb 17.2gb 81 node2 192.168.113.102 data-1
4 5.7mb 9.9gb 7.3gb 17.2gb 57 node3 192.168.113.103 data-2
查看被挂起任务
GET _cat/pending_tasks?v
insertOrder timeInQueue priority source
查看每个节点正在运行的插件
GET _cat/plugins?v
name component version
data-2 x-pack-core 6.2.4
data-2 x-pack-deprecation 6.2.4
data-2 x-pack-graph 6.2.4
data-2 x-pack-logstash 6.2.4
data-2 x-pack-ml 6.2.4
data-2 x-pack-monitoring 6.2.4
data-2 x-pack-security 6.2.4
data-2 x-pack-upgrade 6.2.4
data-2 x-pack-watcher 6.2.4
client-1 x-pack-core 6.2.4
client-1 x-pack-deprecation 6.2.4
client-1 x-pack-graph 6.2.4
client-1 x-pack-logstash 6.2.4
client-1 x-pack-ml 6.2.4
client-1 x-pack-monitoring 6.2.4
client-1 x-pack-security 6.2.4
client-1 x-pack-upgrade 6.2.4
client-1 x-pack-watcher 6.2.4
master-1 x-pack-core 6.2.4
master-1 x-pack-deprecation 6.2.4
master-1 x-pack-graph 6.2.4
master-1 x-pack-logstash 6.2.4
master-1 x-pack-ml 6.2.4
master-1 x-pack-monitoring 6.2.4
master-1 x-pack-security 6.2.4
master-1 x-pack-upgrade 6.2.4
master-1 x-pack-watcher 6.2.4
data-1 x-pack-core 6.2.4
data-1 x-pack-deprecation 6.2.4
data-1 x-pack-graph 6.2.4
data-1 x-pack-logstash 6.2.4
data-1 x-pack-ml 6.2.4
data-1 x-pack-monitoring 6.2.4
data-1 x-pack-security 6.2.4
data-1 x-pack-upgrade 6.2.4
data-1 x-pack-watcher 6.2.4
查看每个节点的自定义属性
GET /_cat/nodeattrs?v
node host ip attr value
data-2 node3 192.168.113.103 ml.machine_memory 1028517888
data-2 node3 192.168.113.103 ml.max_open_jobs 20
data-2 node3 192.168.113.103 ml.enabled true
client-1 node4 192.168.113.104 ml.machine_memory 1856888832
client-1 node4 192.168.113.104 ml.max_open_jobs 20
client-1 node4 192.168.113.104 ml.enabled true
master-1 node1 192.168.113.101 ml.machine_memory 1028517888
master-1 node1 192.168.113.101 ml.max_open_jobs 20
master-1 node1 192.168.113.101 ml.enabled true
data-1 node2 192.168.113.102 ml.machine_memory 1028517888
data-1 node2 192.168.113.102 ml.max_open_jobs 20
data-1 node2 192.168.113.102 ml.enabled true
查看索引分片的恢复视图
##索引分片的恢复视图,包括正在进行和先前已完成的恢复
##只要索引分片移动到群集中的其他节点，就会发生恢复事件
GET _cat/recovery/.kibana?v&format=json&pretty
[
{
"index": ".kibana",
"shard": "0",
"time": "446ms",
"type": "empty_store",
"stage": "done",
"source_host": "n/a",
"source_node": "n/a",
"target_host": "node2",
"target_node": "data-1",
"repository": "n/a",
"snapshot": "n/a",
"files": "0",
"files_recovered": "0",
"files_percent": "0.0%",
"files_total": "0",
"bytes": "0",
"bytes_recovered": "0",
"bytes_percent": "0.0%",
"bytes_total": "0",
"translog_ops": "0",
"translog_ops_recovered": "0",
"translog_ops_percent": "100.0%"
},
{
"index": ".kibana",
"shard": "0",
"time": "2s",
"type": "peer",
"stage": "done",
"source_host": "node2",
"source_node": "data-1",
"target_host": "node3",
"target_node": "data-2",
"repository": "n/a",
"snapshot": "n/a",
"files": "1",
"files_recovered": "1",
"files_percent": "100.0%",
"files_total": "1",
"bytes": "230",
"bytes_recovered": "230",
"bytes_percent": "100.0%",
"bytes_total": "230",
"translog_ops": "0",
"translog_ops_recovered": "0",
"translog_ops_percent": "100.0%"
}
]
查看每个数据节点上fielddata当前占用的堆内存
全文检索用倒排索引非常合适;但过滤、分组聚合、排序这些操作，正排索引更合适。
ES中引入了fielddata的数据结构用来做正排索引。如果需要对某一个字段排序、分组聚合、过滤，则可将字段设置成fielddata。
默认情况下:
text类型的字段是不能分组及排序的，如需要则需要开启该字段的fielddata=true,但是这样耗费大量的内存，不建议这么使用。
keyword类型默认可分组及排序。
fielddata默认是采用懒加载的机制加载到堆内存中。当某个字段基数特别大，可能会出现OOM。
GET _cat/fielddata?v&h=node,field,size
node field size
data-1 kibana_stats.kibana.uuid 0b
data-1 kibana_stats.kibana.status 0b
data-2 kibana_stats.kibana.uuid 0b
data-2 kibana_stats.kibana.status 0b
##对某一字段进行查看
GET _cat/fielddata?v&h=node,field,size&fields=kibana_stats.kibana.uuid
node field size
data-2 kibana_stats.kibana.uuid 0b
data-1 kibana_stats.kibana.uuid 0b
查看注册的快照仓库
GET _cat/repositories?v
id type
查看快照仓库下的快照
##可将ES中的一个或多个索引定期备份到如HDFS、S3等更可靠的文件系统，以应对灾难性的故障
##第一次快照是一个完整拷贝，所有后续快照则保留的是已存快照和新数据之间的差异
##当出现灾难性故障时，可基于快照恢复
GET _cat/snapshots/repo1?v
查看每个节点线程池的统计信息
##查看每个节点bulk线程池的统计信息
## actinve（活跃的），queue（队列中的）和 reject（拒绝的）
GET _cat/thread_pool/bulk?v&format=json&pretty
[
{
"node_name": "data-2",
"name": "bulk",
"active": "0",
"queue": "0",
"rejected": "0"
},
{
"node_name": "client-1",
"name": "bulk",
"active": "0",
"queue": "0",
"rejected": "0"
},
{
"node_name": "master-1",
"name": "bulk",
"active": "0",
"queue": "0",
"rejected": "0"
},
{
"node_name": "data-1",
"name": "bulk",
"active": "0",
"queue": "0",
"rejected": "0"
}
]
查看索引
GET _cat/indices/.monitoring*?v&h=index,health
index health
.monitoring-es-6-2018.08.25 green
.monitoring-kibana-6-2018.08.25 green
查看别名
GET _cat/aliases?v&h=alias,index
alias index
.security .security-6
查看索引模板
GET _cat/templates?v&format=json&pretty
[
{
"name": "logstash-index-template",
"index_patterns": "[.logstash]",
"order": "0",
"version": null
},
{
"name": "security_audit_log",
"index_patterns": "[.security_audit_log*]",
"order": "2147483647",
"version": null
},
{
"name": ".monitoring-kibana",
"index_patterns": "[.monitoring-kibana-6-*]",
"order": "0",
"version": "6020099"
},
{
"name": ".watches",
"index_patterns": "[.watches*]",
"order": "2147483647",
"version": null
},
{
"name": ".monitoring-beats",
"index_patterns": "[.monitoring-beats-6-*]",
"order": "0",
"version": "6020099"
},
{
"name": ".ml-notifications",
"index_patterns": "[.ml-notifications]",
"order": "0",
"version": "6020499"
},
{
"name": ".ml-anomalies-",
"index_patterns": "[.ml-anomalies-*]",
"order": "0",
"version": "6020499"
},
{
"name": ".ml-state",
"index_patterns": "[.ml-state]",
"order": "0",
"version": "6020499"
},
{
"name": "security-index-template",
"index_patterns": "[.security-*]",
"order": "1000",
"version": null
},
{
"name": ".watch-history-7",
"index_patterns": "[.watcher-history-7*]",
"order": "2147483647",
"version": null
},
{
"name": ".ml-meta",
"index_patterns": "[.ml-meta]",
"order": "0",
"version": "6020499"
},
{
"name": ".monitoring-alerts",
"index_patterns": "[.monitoring-alerts-6]",
"order": "0",
"version": "6020099"
},
{
"name": ".monitoring-logstash",
"index_patterns": "[.monitoring-logstash-6-*]",
"order": "0",
"version": "6020099"
},
{
"name": ".triggered_watches",
"index_patterns": "[.triggered_watches*]",
"order": "2147483647",
"version": null
},
{
"name": ".monitoring-es",
"index_patterns": "[.monitoring-es-6-*]",
"order": "0",
"version": "6020099"
},
{
"name": "kibana_index_template:.kibana",
"index_patterns": "[.kibana]",
"order": "0",
"version": null
}
]
查看单个或某类或整个集群文档数
##整个集群文档数
GET _cat/count?v
epoch timestamp count
1535185950 16:32:30 3008
##某类索引文档数
GET _cat/count/.monitoring*?v
epoch timestamp count
1535186185 16:36:25 2162
注意:只包含实际文档数，不包括尚未清除的已删除文档。
查看每个索引的分片
GET _cat/shards?v&format=json&pretty&s=index
[
{
"index": ".kibana",
"shard": "0",
"prirep": "p",
"state": "STARTED",
"docs": "1",
"store": "4kb",
"ip": "192.168.113.102",
"node": "data-1"
},
{
"index": ".kibana",
"shard": "0",
"prirep": "r",
"state": "STARTED",
"docs": "1",
"store": "4kb",
"ip": "192.168.113.103",
"node": "data-2"
},
{
"index": ".monitoring-es-6-2018.08.25",
"shard": "0",
"prirep": "p",
"state": "STARTED",
"docs": "2557",
"store": "1.6mb",
"ip": "192.168.113.102",
"node": "data-1"
},
{
"index": ".monitoring-es-6-2018.08.25",
"shard": "0",
"prirep": "r",
"state": "STARTED",
"docs": "2557",
"store": "1.5mb",
"ip": "192.168.113.103",
"node": "data-2"
},
{
"index": ".monitoring-kibana-6-2018.08.25",
"shard": "0",
"prirep": "p",
"state": "STARTED",
"docs": "211",
"store": "110.1kb",
"ip": "192.168.113.102",
"node": "data-1"
},
{
"index": ".monitoring-kibana-6-2018.08.25",
"shard": "0",
"prirep": "r",
"state": "STARTED",
"docs": "211",
"store": "110.1kb",
"ip": "192.168.113.103",
"node": "data-2"
},
{
"index": ".security-6",
"shard": "0",
"prirep": "p",
"state": "STARTED",
"docs": "3",
"store": "9.8kb",
"ip": "192.168.113.102",
"node": "data-1"
},
{
"index": ".security-6",
"shard": "0",
"prirep": "r",
"state": "STARTED",
"docs": "3",
"store": "9.8kb",
"ip": "192.168.113.103",
"node": "data-2"
}
]
查看每个索引的segment
GET _cat/segments/.kibana?v&format=json&pretty
[
{
"index": ".kibana",
"shard": "0",
"prirep": "p",
"ip": "192.168.113.102",
"segment": "_2",
"generation": "2",
"docs.count": "1",
"docs.deleted": "0",
"size": "3.7kb",
"size.memory": "1346",
"committed": "true",
"searchable": "true",
"version": "7.2.1",
"compound": "true"
},
{
"index": ".kibana",
"shard": "0",
"prirep": "r",
"ip": "192.168.113.103",
"segment": "_2",
"generation": "2",
"docs.count": "1",
"docs.deleted": "0",
"size": "3.7kb",
"size.memory": "1346",
"committed": "true",
"searchable": "true",
"version": "7.2.1",
"compound": "true"
}
]
