--- title: Use ES|QL across clusters description: Run a single ES|QL query across multiple Elasticsearch clusters. Covers role and user setup, query syntax, cross-cluster metadata, and enrich and skip-unavailable behavior. url: https://www.elastic.co/elastic/docs-builder/docs/3466/reference/query-languages/esql/esql-cross-clusters products: - Elasticsearch applies_to: - Elastic Cloud Serverless: Unavailable - Elastic Stack: Generally available since 9.1, Preview in 9.0 --- # Use ES|QL across clusters With ES|QL, you can execute a single query across multiple clusters. This page covers remote clusters and cross-cluster search, which are not available in Elastic Cloud Serverless. In Serverless, you can use cross-project search instead. To learn how to query across multiple Serverless projects using CPS, see [Query across Serverless projects with ES|QL](https://www.elastic.co/elastic/docs-builder/docs/3466/reference/query-languages/esql/esql-cross-serverless-projects). ## Prerequisites - ES|QL cross-cluster search requires an [Enterprise subscription](https://www.elastic.co/subscriptions) on both the local (querying) cluster and every remote cluster. - [Remote clusters](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/deploy-manage/remote-clusters) must be configured before running ES|QL across clusters. The destination cluster must be configured as a remote cluster on the local cluster, and the remote cluster connection must be correctly established. For setup instructions, refer to [Set up remote clusters](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/deploy-manage/remote-clusters#setup). - The local node receiving the query must have the [`remote_cluster_client`](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/deploy-manage/distributed-architecture/clusters-nodes-shards/node-roles#remote-node) node role to connect to the remote clusters. - ES|QL across clusters requires the remote cluster connection to use the [API key-based security model](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/deploy-manage/remote-clusters/security-models#api-key). To verify which security model is active, run `GET _remote/info`. When API key authentication is in use, the response includes `"cluster_credentials"`. - For supported version pairings, see [Supported cross-cluster search configurations](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/explore-analyze/cross-cluster-search#ccs-supported-configurations). ## Configure roles and users ES|QL cross-cluster search requires some additional permissions beyond a standard Query DSL search. The following example creates a role that can query remote indices using ES|QL. The final `remote_cluster` privilege is required for remote enrich operations. ```json { "cluster": ["cross_cluster_search"], <1> "indices": [ { "names" : [""], <2> "privileges": ["read"] } ], "remote_indices": [ <3> { "names": [ "logs-*" ], "privileges": [ "read","read_cross_cluster" ], <4> "clusters" : ["my_remote_cluster"] <5> } ], "remote_cluster": [ <6> { "privileges": [ "monitor_enrich" ], "clusters": [ "my_remote_cluster" ] } ] } ``` You then need a user or API key with the permissions you just created. The following example API call creates a user with the `remote1` role. ```json { "password" : "", "roles" : [ "remote1" ] } ``` For the full reference of cross-cluster role privileges across all deployment types, refer to [Configure privileges for cross-cluster search](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/deploy-manage/remote-clusters/remote-clusters-api-key#_configure_privileges_for_ccs). All cross-cluster requests from the local cluster are bound by the cross-cluster API key's privileges, which are controlled by the remote cluster's administrator. Local roles can only further reduce these permissions; they cannot increase access beyond what the API key allows.For example, if the remote cluster's administrator creates a cross-cluster API key that excludes the indices you need, the role you defined on the local cluster cannot grant access to them. ## Query across multiple clusters In the examples that follow, `cluster_one`, `cluster_two`, and `cluster_three` represent remote clusters that you've already configured on the local cluster where the query runs. The cluster name in each `FROM` clause is the alias you assigned during remote cluster setup. In the `FROM` command, specify data streams and indices on remote clusters using the format `:`. For instance, the following ES|QL request queries the `my-index-000001` index on a single remote cluster named `cluster_one`: ```esql FROM cluster_one:my-index-000001 | LIMIT 10 ``` Similarly, this ES|QL request queries the `my-index-000001` index from three clusters: - The local ("querying") cluster - Two remote clusters, `cluster_one` and `cluster_two` ```esql FROM my-index-000001,cluster_one:my-index-000001,cluster_two:my-index-000001 | LIMIT 10 ``` Likewise, this ES|QL request queries the `my-index-000001` index from all remote clusters (`cluster_one`, `cluster_two`, and `cluster_three`): ```esql FROM *:my-index-000001 | LIMIT 10 ``` ## Cross-cluster metadata Using the `"include_ccs_metadata": true` option, you can request that ES|QL cross-cluster search responses include metadata about the search on each cluster (when the response format is JSON). Here we show an example using the async search endpoint. Cross-cluster search metadata is also present in the synchronous search endpoint response when requested. If the search returns partial results and there are partial shard or remote cluster failures, `_clusters` metadata containing the failures is included in the response regardless of the `include_ccs_metadata` parameter. ```json { "query": """ FROM my-index-000001,cluster_one:my-index-000001,cluster_two:my-index* | STATS COUNT(http.response.status_code) BY user.id | LIMIT 2 """, "include_ccs_metadata": true } ``` Which returns: ```json { "is_running": false, "took": 42, "is_partial": false, "columns" : [ { "name" : "COUNT(http.response.status_code)", "type" : "long" }, { "name" : "user.id", "type" : "keyword" } ], "values" : [ [4, "elkbee"], [1, "kimchy"] ], "_clusters": { "total": 3, "successful": 3, "running": 0, "skipped": 0, "partial": 0, "failed": 0, "details": { "(local)": { "status": "successful", "indices": "blogs", "took": 41, "_shards": { "total": 13, "successful": 13, "skipped": 0, "failed": 0 } }, "cluster_one": { "status": "successful", "indices": "cluster_one:my-index-000001", "took": 38, "_shards": { "total": 4, "successful": 4, "skipped": 0, "failed": 0 } }, "cluster_two": { "status": "successful", "indices": "cluster_two:my-index*", "took": 40, "_shards": { "total": 18, "successful": 18, "skipped": 1, "failed": 0 } } } } } ``` You can use the cross-cluster metadata to determine whether any data came back from a cluster. For instance, in the query below, the wildcard expression for `cluster_two` did not resolve to a concrete index (or indices). The cluster is, therefore, marked as *skipped* and the total number of shards searched is set to zero. ```json { "query": """ FROM cluster_one:my-index*,cluster_two:logs* | STATS COUNT(http.response.status_code) BY user.id | LIMIT 2 """, "include_ccs_metadata": true } ``` Which returns: ```json { "is_running": false, "took": 55, "is_partial": true, "columns": [ ... ], "values": [ ... ], "_clusters": { "total": 2, "successful": 1, "running": 0, "skipped": 1, "partial": 0, "failed": 0, "details": { "cluster_one": { "status": "successful", "indices": "cluster_one:my-index*", "took": 38, "_shards": { "total": 4, "successful": 4, "skipped": 0, "failed": 0 } }, "cluster_two": { "status": "skipped", "indices": "cluster_two:logs*", "took": 0, "_shards": { "total": 0, "successful": 0, "skipped": 0, "failed": 0 } } } } } ``` For more on partial results and how cluster status is determined when failures occur, see [Cross-cluster search failures](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/explore-analyze/cross-cluster-search#cross-cluster-search-failures). ## Enrich across clusters Enrich in ES|QL across clusters operates similarly to [local enrich](https://www.elastic.co/elastic/docs-builder/docs/3466/reference/query-languages/esql/commands/enrich). If the enrich policy and its enrich indices are consistent across all clusters, write the enrich command as you would without remote clusters. In this default mode, ES|QL can execute the enrich command on either the local cluster or the remote clusters, aiming to minimize computation or inter-cluster data transfer. Ensuring that the policy exists with consistent data on both the local cluster and the remote clusters is critical for ES|QL to produce a consistent query result. Cross-cluster API keys created in versions prior to 8.15 must be replaced or updated to use the new required permissions for ES|QL cross-cluster enrich with the API key-based security model. Refer to the example in the [Use ES|QL across clusters > Configure roles and users](#esql-ccs-security-model-api-key) section. In the following example, the enrich with `hosts` policy can be executed on either the local cluster or the remote cluster `cluster_one`. ```esql FROM my-index-000001,cluster_one:my-index-000001 | ENRICH hosts ON ip | LIMIT 10 ``` Enrich with an ES|QL query against remote clusters only can also happen on the local cluster. This means the following query requires the `hosts` enrich policy to exist on the local cluster as well. ```esql FROM cluster_one:my-index-000001,cluster_two:my-index-000001 | LIMIT 10 | ENRICH hosts ON ip ``` ### Enrich with coordinator mode ES|QL provides the enrich `_coordinator` mode to force ES|QL to execute the enrich command on the local cluster. Use this mode when the enrich policy is not available on the remote clusters or maintaining consistency of enrich indices across clusters is challenging. ```esql FROM my-index-000001,cluster_one:my-index-000001 | ENRICH _coordinator:hosts ON ip | SORT host_name | LIMIT 10 ``` Enrich with the `_coordinator` mode usually increases inter-cluster data transfer and workload on the local cluster. ### Enrich with remote mode ES|QL also provides the enrich `_remote` mode to force ES|QL to execute the enrich command independently on each remote cluster where the target indices reside. This mode is useful for managing different enrich data on each cluster, such as detailed information of hosts for each region where the target (main) indices contain log events from these hosts. In the following example, the `hosts` enrich policy is required to exist on all remote clusters: the "querying" cluster (as local indices are included), the remote cluster `cluster_one`, and `cluster_two`. ```esql FROM my-index-000001,cluster_one:my-index-000001,cluster_two:my-index-000001 | ENRICH _remote:hosts ON ip | SORT host_name | LIMIT 10 ``` A `_remote` enrich cannot be executed after a [`STATS`](https://www.elastic.co/elastic/docs-builder/docs/3466/reference/query-languages/esql/commands/stats-by) command. The following example would result in an error: ```esql FROM my-index-000001,cluster_one:my-index-000001,cluster_two:my-index-000001 | STATS COUNT(*) BY ip | ENRICH _remote:hosts ON ip | SORT host_name | LIMIT 10 ``` ### Multiple enrich commands You can include multiple enrich commands in the same query with different modes. ES|QL attempts to execute them accordingly. For example, this query performs two enrich commands, first with the `hosts` policy on any cluster and then with the `vendors` policy on the local cluster. ```esql FROM my-index-000001,cluster_one:my-index-000001,cluster_two:my-index-000001 | ENRICH hosts ON ip | ENRICH _coordinator:vendors ON os | LIMIT 10 ``` A `_remote` enrich command can't be executed after a `_coordinator` enrich command. The following example would result in an error. ```esql FROM my-index-000001,cluster_one:my-index-000001,cluster_two:my-index-000001 | ENRICH _coordinator:hosts ON ip | ENRICH _remote:vendors ON os | LIMIT 10 ``` ## Excluding clusters or indices from ES|QL query To exclude an entire cluster, prefix the cluster alias with a minus sign in the `FROM` command, for example: `-my_cluster:*`: ```esql FROM my-index-000001,cluster*:my-index-000001,-cluster_three:* | LIMIT 10 ``` To exclude a specific remote index, prefix the index with a minus sign in the `FROM` command, such as `my_cluster:-my_index`: ```esql FROM my-index-000001,cluster*:my-index-*,cluster_three:-my-index-000001 | LIMIT 10 ``` Elastic Stack: Planned The form `-my_cluster:my_index` is also accepted as an alternative for `my_cluster:-my_index`. For example, the following query is equivalent to the one above: ```esql FROM my-index-000001,cluster*:my-index-*,-cluster_three:my-index-000001 | LIMIT 10 ``` The two forms have different semantics: `-my_cluster:*` is a *cluster-level* exclusion that requires the cluster to have been included by a preceding expression (`-cluster_three:*` on its own is rejected), while `-my_cluster:` is an *index-level* exclusion equivalent to `my_cluster:-` and may appear standalone. ## Skipping problematic remote clusters Cross-cluster search for ES|QL behavior when there are problems connecting to or running a query on remote clusters differs between versions. Remote clusters are configured with the `skip_unavailable: true` setting by default. With this setting, clusters are marked as `skipped` or `partial` rather than causing queries to fail in the following scenarios: - The remote cluster is disconnected from the querying cluster, either before or during the query execution. - The remote cluster does not have the requested index, or it is not accessible due to security settings. - An error happened while processing the query on the remote cluster. The `partial` status means the remote query either has errors or was interrupted by an explicit user action, but some data can be returned.Even when `skip_unavailable` is set to `true`, queries fail if none of the specified indices exist. For example, the following queries fail: ```esql FROM cluster_one:missing-index | LIMIT 10 FROM cluster_one:missing-index* | LIMIT 10 FROM cluster_one:missing-index*,cluster_two:missing-index | LIMIT 10 ``` If a remote cluster disconnects from the querying cluster, cross-cluster search for ES|QL sets it to `skipped` and continues the query with other clusters, unless the remote cluster's `skip_unavailable` setting is set to `false`, in which case the query fails. For broader context on the `skip_unavailable` setting, including how it interacts with `allow_no_indices` and `ignore_unavailable`, see [Optional remote clusters](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/explore-analyze/cross-cluster-search#skip-unavailable-clusters). ## Query across clusters during an upgrade You can still search a remote cluster while performing a rolling upgrade on the local cluster. However, the local node receiving the query must have an "upgrade from" and "upgrade to" version that is compatible with the remote cluster's gateway node. Running multiple versions of Elasticsearch in the same cluster beyond the duration of an upgrade is not supported. For more information about upgrades, see [Upgrading Elasticsearch](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3466/deploy-manage/upgrade/deployment-or-cluster). ## Query across Serverless projects - Elastic Cloud Serverless: Preview You can use cross-project search (CPS) to query across multiple linked serverless projects. To learn more, refer to [Query across Serverless projects](https://www.elastic.co/elastic/docs-builder/docs/3466/reference/query-languages/esql/esql-cross-serverless-projects).