﻿---
title: Remote clusters on Elastic Cloud on Kubernetes
description: When using remote cluster connections with ECK, the setup process varies depending on how both the local and remote clusters are deployed: When both clusters...
url: https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/eck-remote-clusters-landing
products:
  - Elastic Cloud on Kubernetes
applies_to:
  - Elastic Cloud on Kubernetes: Generally available
---

# Remote clusters on Elastic Cloud on Kubernetes
The [remote clusters feature](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters) in Elasticsearch enables you to establish uni-directional connections to a remote cluster. This functionality is used in [cross-cluster replication (CCR)](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/tools/cross-cluster-replication/set-up-cross-cluster-replication) and [cross-cluster search (CCS)](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/explore-analyze/cross-cluster-search).
<admonition title="Note about terminology">
  In the case of remote clusters, the Elasticsearch cluster or deployment initiating the connection and requests is often referred to as the **local cluster**, while the Elasticsearch cluster or deployment receiving the requests is referred to as the **remote cluster**.
</admonition>

When using remote cluster connections with ECK, the setup process varies depending on how both the local and remote clusters are deployed:
- When both clusters are managed by the same operator, ECK can automate certificate and API-key management, connection configuration, and reconciliation.
- When external clusters are involved, ECK provides limited automation, and additional manual configuration is required on both the local and remote clusters.


## Prerequisites

To use CCS or CCR, your Elasticsearch clusters must meet the following criteria:
- The local and remote clusters must run on compatible versions of Elasticsearch. Review the version compatibility table.
  <dropdown title="Version compatibility table">
  - Any node can communicate with another node on the same major version. For example, 9.0 can talk to any 9.x node.
  - Version compatibility is symmetric, meaning that if 7.16 can communicate with 8.0, 8.0 can also communicate with 7.16. The following table depicts version compatibility between local and remote nodes.

  <note>
  Version 8.19 is the final minor release in the 8.x series. Unlike past releases, 8.18 was launched simultaneously with 9.0, allowing cross-version compatibility between them. Hence, as shown in the compatibility table, 8.18 can search 9.0 clusters, but only 8.19 supports searching 9.1 and later.
  </note>


  |                       |                        |     |     |     |     |     |     |     |     |     |     |      |      |      |      |      |      |      |      |      |      |     |     |     |     |
  |-----------------------|------------------------|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|------|------|------|------|------|------|------|------|------|------|-----|-----|-----|-----|
  |                       | Remote cluster version |     |     |     |     |     |     |     |     |     |     |      |      |      |      |      |      |      |      |      |      |     |     |     |     |
  | Local cluster version | 7.17                   | 8.0 | 8.1 | 8.2 | 8.3 | 8.4 | 8.5 | 8.6 | 8.7 | 8.8 | 8.9 | 8.10 | 8.11 | 8.12 | 8.13 | 8.14 | 8.15 | 8.16 | 8.17 | 8.18 | 8.19 | 9.0 | 9.1 | 9.2 | 9.3 |
  | 7.17                  | ✅                      | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.0                   | ✅                      | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.1                   | ❌                      | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.2                   | ❌                      | ❌   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.3                   | ❌                      | ❌   | ❌   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.4                   | ❌                      | ❌   | ❌   | ❌   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.5                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.6                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ✅   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.7                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ✅   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.8                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ✅   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.9                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ✅   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.10                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ✅   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.11                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.12                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.13                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.14                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.15                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ✅    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.16                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ✅    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.17                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ✅    | ✅    | ✅    | ✅    | ❌   | ❌   | ❌   | ❌   |
  | 8.18                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ✅    | ✅    | ✅    | ✅   | ❌   | ❌   | ❌   |
  | 8.19                  | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ✅    | ✅    | ✅   | ✅   | ✅   | ✅   |
  | 9.0                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ✅    | ❌    | ✅   | ✅   | ✅   | ✅   |
  | 9.1                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ✅   | ✅   | ✅   | ✅   |
  | 9.2                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌   | ✅   | ✅   | ✅   |
  | 9.3                   | ❌                      | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌   | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌    | ❌   | ❌   | ✅   | ✅   |
  </dropdown>
- Network connectivity between the clusters. Review the [connection modes](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/connection-modes) and the [security models](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/security-models) to understand the connectivity requirements for your specific setup. Remote cluster connections can operate through Kubernetes services, load balancers, reverse proxies, or other intermediaries, as long as the local cluster can reach the remote cluster’s endpoint.
- The remote clusters feature on ECK requires a valid Enterprise license or Enterprise trial license. Check [the license documentation](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/license/manage-your-license-in-eck) for more details about managing licenses.


## Set up remote clusters with Elastic Cloud on Kubernetes

Use one of the following guides depending on how the local and remote clusters are deployed.
Connect from ECK-managed clusters:
- [Connect to Elasticsearch clusters in the same ECK environment](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/eck-remote-clusters)
- [Connect to a different ECK environment](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/eck-remote-clusters-to-other-eck)
- [Connect to external clusters or deployments](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/eck-remote-clusters-to-external)

Connect to ECK-managed clusters from other deployment types:
- [Connect Elastic Cloud Hosted deployments to Elastic Cloud on Kubernetes clusters](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/ec-enable-ccs-for-eck)
- [Connect Elastic Cloud Enterprise deployments to Elastic Cloud on Kubernetes clusters](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/ece-enable-ccs-for-eck)
- [Connect self-managed Elasticsearch clusters to ECK](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5072/deploy-manage/remote-clusters/self-remote-cluster-eck)