> For the complete documentation index, see [llms.txt](https://vaansun.gitbook.io/elk-old-version/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://vaansun.gitbook.io/elk-old-version/elasticsearch/monitor/jian-kong-xiang-guan-jie-kou/cat-cmd.md). # cat 接口的命令行使用 之前介绍的各种接口数据，其响应数据都是 JSON 格式，更适用于程序处理。对于我们日常运维，在 Linux 命令行终端环境来说，简单的分行和分列表格才是更方便的样式。为此，Elasticsearch 提供了 cat 接口。 cat 接口可以读取各种监控数据，可用接口列表如下： * /\_cat/allocation * /\_cat/shards * /\_cat/shards/{index} * /\_cat/master * /\_cat/nodes * /\_cat/indices * /\_cat/indices/{index} * /\_cat/segments * /\_cat/segments/{index} * /\_cat/count * /\_cat/count/{index} * /\_cat/recovery * /\_cat/recovery/{index} * /\_cat/health * /\_cat/pending\_tasks * /\_cat/aliases * /\_cat/aliases/{alias} * /\_cat/thread\_pool * /\_cat/plugins * /\_cat/fielddata * /\_cat/fielddata/{fields} ## 集群状态 还是以最基础的集群状态为例，采用 cat 接口查询集群状态的命令如下： ``` # curl -XGET http://127.0.0.1:9200/_cat/health 1434300299 00:44:59 es1003 red 39 27 2589 1505 4 1 0 0 ``` 如果单看这行输出，或许不熟悉的用户会有些茫然。可以通过添加 `?v` 参数，输出表头： ``` # curl -XGET http://127.0.0.1:9200/_cat/health?v epoch timestamp cluster status node.total node.data shards pri relo init unassign pending_tasks 1434300334 00:45:34 es1003 green 39 27 2590 1506 5 0 0 0 ``` ## 节点状态 ``` # curl -XGET http://127.0.0.1:9200/_cat/nodes?v host ip heap.percent ram.percent load node.role master name esnode109 10.19.0.109 62 69 6.37 d - 10.19.0.109 esnode096 10.19.0.96 63 69 0.29 - - 10.19.0.96 esnode100 10.19.0.100 56 79 0.07 - m 10.19.0.100 ``` 跟集群状态不一样的是，节点状态数据太多，cat 接口不方便在一行表格中放下所有数据。所以默认的返回，只是最基本的内存和负载数据。具体想看某方面的数据，也是通过请求参数的方式额外指明。比如想看 heap 百分比和最大值： ``` # curl -XGET 'http://127.0.0.1:9200/_cat/nodes?v&h=ip,port,heapPercent,heapMax' ip port heapPercent heapMax 192.168.1.131 9300 66 25gb ``` `h` 请求参数可用的值，可以通过 `?help` 请求参数来查询： ``` # curl -XGET http://127.0.0.1:9200/_cat/nodes?help id | id,nodeId | unique node id host | h | host name ip | i | ip address port | po | bound transport port heap.percent | hp,heapPercent | used heap ratio heap.max | hm,heapMax | max configured heap ram.percent | rp,ramPercent | used machine memory ratio ram.max | rm,ramMax | total machine memory load | l | most recent load avg node.role | r,role,dc,nodeRole | d:data node, c:client node ... ``` 中间第二列就是对应的请求参数的值及其缩写。也就是说上面示例还可以写成： ``` # curl -XGET http://127.0.0.1:9200/_cat/nodes?v&h=i,po,hp,hm ``` ## 索引状态 查询索引列表和存储的数据状态是也是 cat 接口最常用的功能之一。为了方便阅读，默认输出时会把数据大小以更可读的方式自动换算成合适的单位，比如 *3.2tb* 这样。 如果你打算通过 shell 管道做后续处理，那么可以加上 `?bytes` 参数，指明统一采用字节数输出，这样保证在同一个级别上排序： ``` # curl -XGET http://127.0.0.1:9200/_cat/indices?bytes=b | sort -rnk8 green open logstash-mweibo-2015.06.12 26 1 754641614 0 2534955821580 1256680767317 green open logstash-mweibo-2015.06.14 27 1 855516794 0 2419569433696 1222355996673 ``` ## 分片状态 ``` # curl -XGET http://127.0.0.1:9200/_cat/shards?v index shard prirep state docs store ip node logstash-mweibo-h5view-2015.06.10 20 p STARTED 4690968 679.2mb 127.0.0.1 10.19.0.108 logstash-mweibo-h5view-2015.06.10 20 r STARTED 4690968 679.4mb 127.0.0.1 10.19.0.39 logstash-mweibo-h5view-2015.06.10 2 p STARTED 4725961 684.3mb 127.0.0.1 10.19.0.53 logstash-mweibo-h5view-2015.06.10 2 r STARTED 4725961 684.3mb 127.0.0.1 10.19.0.102 ``` 同样，可以用 `?help` 查询其他可用数据细节。比如每个分片的 *segment.count*： ``` # curl -XGET 'http://127.0.0.1:9200/_cat/shards/logstash-mweibo-nginx-2015.06.14?v\&h=n,iic,sc' n iic sc 10.19.0.72 0 42 10.19.0.41 0 36 10.19.0.104 0 32 10.19.0.102 0 40 ``` ## 恢复状态 在出现集群状态波动时，通过这个接口查看数据迁移和恢复速度也是一个非常有用的功能。不过默认输出是把集群历史上所有发生的 recovery 记录都返回出来，所以一般会加上 `?active_only` 参数，仅列出当前还在运行的恢复状态： ``` # curl -XGET 'http://127.0.0.1:9200/_cat/recovery?active_only&v&h=i,s,shost,thost,fp,bp,tr,trp,trt' i s shost thost fp bp tr trp trt logstash-mweibo-2015.06.12 10 esnode041 esnode080 87.6% 35.3% 0 100.0% 0 logstash-mweibo-2015.06.13 10 esnode108 esnode080 95.5% 88.3% 0 100.0% 0 logstash-mweibo-2015.06.14 17 esnode102 esnode080 96.3% 92.5% 0 0.0% 118758 ``` ## 线程池状态 ``` curl -s -XGET http://127.0.0.1:9200/_cat/thread_pool?v host ip bulk.active bulk.queue bulk.rejected index.active index.queue index.rejected search.active search.queue search.rejected esnode073 127.0.0.1 1 0 20669 0 0 50 4 0 0 ``` 包括 merge，optimize，flush，refresh 等其他线程池状态，也可以通过 `?h` 参数指明获取。 --- # Agent Instructions This documentation is published with GitBook. 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