cat nodes API

edit

cat APIs are only intended for human consumption using the command line or Kibana console. They are not intended for use by applications. For application consumption, use the nodes info API.

Returns information about a cluster’s nodes.

Request

edit

GET /_cat/nodes

Prerequisites

edit
  • If the Elasticsearch security features are enabled, you must have the monitor or manage cluster privilege to use this API.

Query parameters

edit
bytes
(Optional, byte size units) Unit used to display byte values.
format
(Optional, string) Short version of the HTTP accept header. Valid values include JSON, YAML, etc.
full_id
(Optional, Boolean) If true, return the full node ID. If false, return the shortened node ID. Defaults to false.
h

(Optional, string) Comma-separated list of column names to display.

If you do not specify which columns to include, the API returns the default columns in the order listed below. If you explicitly specify one or more columns, it only returns the specified columns.

Valid columns are:

ip, i
(Default) IP address, such as 127.0.1.1.
heap.percent, hp, heapPercent
(Default) Maximum configured heap, such as 7.
heap.max, hm, heapMax
(Default) Total heap, such as 4gb.
ram.percent, rp, ramPercent
(Default) Used total memory percentage, such as 47.
file_desc.percent, fdp, fileDescriptorPercent
(Default) Used file descriptors percentage, such as 1.
node.role, r, role, nodeRole

(Default) Roles of the node. Returned values include c (cold node), d (data node), f (frozen node), h (hot node), i (ingest node), l (machine learning node), m (master-eligible node), r (remote cluster client node), s (content node), t (transform node), v (voting-only node), w (warm node), and - (coordinating node only).

For example, dim indicates a master-eligible data and ingest node. See Nodes.

master, m
(Default) Indicates whether the node is the elected master node. Returned values include * (elected master) and - (not elected master).
name, n
(Default) Node name, such as I8hydUG.
id, nodeId
ID of the node, such as k0zy.
pid, p
Process ID, such as 13061.
port, po
Bound transport port, such as 9300.
http_address, http
Bound http address, such as 127.0.0.1:9200.
version, v
Elasticsearch version, such as 8.14.3.
build, b
Elasticsearch build hash, such as 5c03844.
jdk, j
Java version, such as 1.8.0.
disk.total, dt, diskTotal
Total disk space, such as 458.3gb.
disk.used, du, diskUsed
Used disk space, such as 259.8gb.
disk.avail, d, disk, diskAvail
Available disk space, such as 198.4gb.
disk.used_percent, dup, diskUsedPercent
Used disk space percentage, such as 47.
heap.current, hc, heapCurrent
Used heap, such as 311.2mb.
ram.current,rc, ramCurrent
Used total memory, such as 513.4mb.
ram.max, rm, ramMax
Total memory, such as 2.9gb.
file_desc.current, fdc, fileDescriptorCurrent
Used file descriptors, such as 123.
file_desc.max, fdm, fileDescriptorMax
Maximum number of file descriptors, such as 1024.
cpu
Recent system CPU usage as percent, such as 12.
load_1m, l
Most recent load average, such as 0.22.
load_5m, l
Load average for the last five minutes, such as 0.78.
load_15m, l
Load average for the last fifteen minutes, such as 1.24.
uptime, u
Node uptime, such as 17.3m.
completion.size, cs, completionSize
Size of completion, such as 0b.
dense_vector.value_count, dvc, denseVectorCount
Number of indexed dense vector.
fielddata.memory_size, fm, fielddataMemory
Used fielddata cache memory, such as 0b.
fielddata.evictions, fe, fielddataEvictions
Fielddata cache evictions, such as 0.
query_cache.memory_size, qcm, queryCacheMemory
Used query cache memory, such as 0b.
query_cache.evictions, qce, queryCacheEvictions
Query cache evictions, such as 0.
query_cache.hit_count, qchc, queryCacheHitCount
Query cache hit count, such as 0.
query_cache.miss_count, qcmc, queryCacheMissCount
Query cache miss count, such as 0.
request_cache.memory_size, rcm, requestCacheMemory
Used request cache memory, such as 0b.
request_cache.evictions, rce, requestCacheEvictions
Request cache evictions, such as 0.
request_cache.hit_count, rchc, requestCacheHitCount
Request cache hit count, such as 0.
request_cache.miss_count, rcmc, requestCacheMissCount
Request cache miss count, such as 0.
flush.total, ft, flushTotal
Number of flushes, such as 1.
flush.total_time, ftt, flushTotalTime
Time spent in flush, such as 1.
get.current, gc, getCurrent
Number of current get operations, such as 0.
get.time, gti, getTime
Time spent in get, such as 14ms.
get.total, gto, getTotal
Number of get operations, such as 2.
get.exists_time, geti, getExistsTime
Time spent in successful gets, such as 14ms.
get.exists_total, geto, getExistsTotal
Number of successful get operations, such as 2.
get.missing_time, gmti, getMissingTime
Time spent in failed gets, such as 0s.
get.missing_total, gmto, getMissingTotal
Number of failed get operations, such as 1.
indexing.delete_current, idc, indexingDeleteCurrent
Number of current deletion operations, such as 0.
indexing.delete_time, idti, indexingDeleteTime
Time spent in deletions, such as 2ms.
indexing.delete_total, idto, indexingDeleteTotal
Number of deletion operations, such as 2.
indexing.index_current, iic, indexingIndexCurrent
Number of current indexing operations, such as 0.
indexing.index_time, iiti, indexingIndexTime
Time spent in indexing, such as 134ms.
indexing.index_total, iito, indexingIndexTotal
Number of indexing operations, such as 1.
indexing.index_failed, iif, indexingIndexFailed
Number of failed indexing operations, such as 0.
merges.current, mc, mergesCurrent
Number of current merge operations, such as 0.
merges.current_docs, mcd, mergesCurrentDocs
Number of current merging documents, such as 0.
merges.current_size, mcs, mergesCurrentSize
Size of current merges, such as 0b.
merges.total, mt, mergesTotal
Number of completed merge operations, such as 0.
merges.total_docs, mtd, mergesTotalDocs
Number of merged documents, such as 0.
merges.total_size, mts, mergesTotalSize
Size of current merges, such as 0b.
merges.total_time, mtt, mergesTotalTime
Time spent merging documents, such as 0s.
refresh.total, rto, refreshTotal
Number of refreshes, such as 16.
refresh.time, rti, refreshTime
Time spent in refreshes, such as 91ms.
script.compilations, scrcc, scriptCompilations
Total script compilations, such as 17.
script.cache_evictions, scrce, scriptCacheEvictions
Total compiled scripts evicted from cache, such as 6.
search.fetch_current, sfc, searchFetchCurrent
Current fetch phase operations, such as 0.
search.fetch_time, sfti, searchFetchTime
Time spent in fetch phase, such as 37ms.
search.fetch_total, sfto, searchFetchTotal
Number of fetch operations, such as 7.
search.open_contexts, so, searchOpenContexts
Open search contexts, such as 0.
search.query_current, sqc, searchQueryCurrent
Current query phase operations, such as 0.
search.query_time, sqti, searchQueryTime
Time spent in query phase, such as 43ms.
search.query_total, sqto, searchQueryTotal
Number of query operations, such as 9.
search.scroll_current, scc, searchScrollCurrent
Open scroll contexts, such as 2.
search.scroll_time, scti, searchScrollTime
Time scroll contexts held open, such as 2m.
search.scroll_total, scto, searchScrollTotal
Completed scroll contexts, such as 1.
segments.count, sc, segmentsCount
Number of segments, such as 4.
segments.memory, sm, segmentsMemory
Memory used by segments, such as 1.4kb.
segments.index_writer_memory, siwm, segmentsIndexWriterMemory
Memory used by index writer, such as 18mb.
segments.version_map_memory, svmm, segmentsVersionMapMemory
Memory used by version map, such as 1.0kb.
segments.fixed_bitset_memory, sfbm, fixedBitsetMemory
Memory used by fixed bit sets for nested object field types and type filters for types referred in join fields, such as 1.0kb.
suggest.current, suc, suggestCurrent
Number of current suggest operations, such as 0.
suggest.time, suti, suggestTime
Time spent in suggest, such as 0.
suggest.total, suto, suggestTotal
Number of suggest operations, such as 0.
shard_stats.total_count, sstc, shards, shardStatsTotalCount
Number of shards assigned.
mappings.total_count, mtc, mappingsTotalCount
Number of mappings, including runtime and object fields.
mappings.total_estimated_overhead_in_bytes, mteo, mappingsTotalEstimatedOverheadInBytes
Estimated heap overhead, in bytes, of mappings on this node, which allows for 1KiB of heap for every mapped field.
help
(Optional, Boolean) If true, the response includes help information. Defaults to false.
master_timeout
(Optional, time units) Period to wait for the master node. If the master node is not available before the timeout expires, the request fails and returns an error. Defaults to 30s. Can also be set to -1 to indicate that the request should never timeout.
s
(Optional, string) Comma-separated list of column names or column aliases used to sort the response.
time
(Optional, time units) Unit used to display time values.
v
(Optional, Boolean) If true, the response includes column headings. Defaults to false.
include_unloaded_segments
(Optional, Boolean) If true, the response includes information from segments that are not loaded into memory. Defaults to false.

Examples

edit

Example with default columns

edit
response = client.cat.nodes(
  v: true
)
puts response
GET /_cat/nodes?v=true

The API returns the following response:

ip        heap.percent ram.percent cpu load_1m load_5m load_15m node.role master name
127.0.0.1           65          99  42    3.07                  dim       *      mJw06l1

The ip, heap.percent, ram.percent, cpu, and load_* columns provide the IP addresses and performance information of each node.

The node.role, master, and name columns provide information useful for monitoring an entire cluster, particularly large ones.

Example with explicit columns

edit

The following API request returns the id, ip, port, v (version), and m (master) columns.

response = client.cat.nodes(
  v: true,
  h: 'id,ip,port,v,m'
)
puts response
GET /_cat/nodes?v=true&h=id,ip,port,v,m

The API returns the following response:

id   ip        port  v         m
veJR 127.0.0.1 59938 8.14.3 *