/_cat

/_cat/allocation      # 查看单节点的shard分配情况
/_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         # 查看所有index的详细信息
/_cat/indices/{index} # 查看指定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 
/_cat/recovery/{index}# 查看指定索引shard的recovery过程
/_cat/health          # 集群当前状态：红、黄、绿
/_cat/pending_tasks   # 查看集群的pending task
/_cat/aliases         # 查看所有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 
/_cat/nodeattrs              # 查看单节点的自定义属性
/_cat/repositories           # 注册快照存储库
/_cat/templates              # 模板信息



v参数 显示表头


节点信息
/_cat/nodes?v
ip          heap.percent ram.percent cpu load_1m load_5m load_15m node.role master name
xx.xx.xx.xx           31          31   0    0.16    0.15     0.09 mdi       -      esnode3
xx.xx.xx.xx           44          31   0    0.16    0.15     0.09 mdi       *      esnode1
xx.xx.xx.xx           31          31   0    0.16    0.15     0.09 mdi       -      esnode2

top -p 2532833,2533097,2533408

top - 09:07:34 up 350 days, 18:47,  3 users,  load average: 0.15, 0.14, 0.10
Tasks:   3 total,   0 running,   3 sleeping,   0 stopped,   0 zombie
%Cpu(s):  0.2 us,  0.1 sy,  0.0 ni, 99.6 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem : 26353670+total, 18188374+free, 69879832 used, 11773140 buff/cache
KiB Swap:        0 total,        0 free,        0 used. 18404155+avail Mem 

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND                             
2532833 admin     20   0   20.1g   2.7g  16604 S   0.7  1.1  16:01.27 java                                
2533097 admin     20   0   16.0g   2.6g  16520 S   0.3  1.0  10:25.33 java                                
2533408 admin     20   0   15.1g   2.6g  16512 S   0.3  1.1  10:02.77 java                                


free -h
              total        used        free      shared  buff/cache   available
Mem:           251G         66G        173G        3.9G         11G        175G
Swap:            0B          0B          0B

heap.percent ram.percent 数据感觉不太对


分片信息
/_cat/shards?v
index shard prirep state   docs   store ip          node
bank  3     r      STARTED  200 128.1kb xx.xx.xx.xx esnode3
bank  3     p      STARTED  200 128.1kb xx.xx.xx.xx esnode1
bank  1     p      STARTED  191 122.8kb xx.xx.xx.xx esnode1
bank  1     r      STARTED  191 122.8kb xx.xx.xx.xx esnode2
bank  4     p      STARTED  201 128.8kb xx.xx.xx.xx esnode3
bank  4     r      STARTED  201 128.8kb xx.xx.xx.xx esnode2
bank  2     r      STARTED  211 134.4kb xx.xx.xx.xx esnode1
bank  2     p      STARTED  211 134.4kb xx.xx.xx.xx esnode2
bank  0     r      STARTED  196 125.9kb xx.xx.xx.xx esnode3
bank  0     p      STARTED  196 125.9kb xx.xx.xx.xx esnode1


index 索引名
shard 分片序号
prirep p 主分片, r 复制分片
store 分片占用存储空间
node  节点名
docs 文档数



索引信息
/_cat/indices?v

health status index uuid                   pri rep docs.count docs.deleted store.size pri.store.size
green  open   pets  ai5NF914RV6d20O1Ef2z8g   5   1          1            0      8.6kb          4.3kb
green  open   bank  UFz7EVmqS4m72H3IUDxcBA   5   1        999            0      1.2mb        640.2kb
green  open   blogs v_s4imPNQbKem1gThEMvHA   5   1          2            0     14.9kb          7.4kb


health           索引的健康状态
index            索引名
pri              索引主分片数量
rep              索引复制分片数
store.size       索引主分片 复制分片 总占用存储空间
pri.store.size   索引总占用空间, 不计算复制分片 占用空间


green yellow  red
  
  Green means everything is good (cluster is fully functional), 
  yellow means all data is available but some replicas are not yet allocated (cluster is fully functional), 
  and red means some data is not available for whatever reason. 
  
  Note that even if a cluster is red, it still is partially functional 
  (it will continue to serve search requests from the available shards) 
  but you will likely need to fix it ASAP since you have missing data.
  
  yellow  一些副本没有分配
  red 一些数据不可用 (主分片丢失)