With CSS, when an Elasticsearch cluster's security needs change, you can change its security mode settings.
Configure the security mode based on the security needs of your cluster.
Cluster Type | Key Settings | Description | Applicable Scenario |
|---|---|---|---|
Non-security mode cluster | Security Mode: disabled | Access to such a cluster requires no user authentication, and data will be transmitted in plaintext using HTTP. | Use when creating a cluster for internal testing or workloads that have a low security standard.
Make sure the cluster is deployed in a secure environment. Do not expose the cluster's network interface to the public network. |
Security-mode cluster | Security-mode cluster + HTTP:
| Such a cluster requires user authentication. It supports access control and data encryption, and it uses HTTP to transmit data in plaintext. | Use to balance security and performance.
Make sure the cluster is deployed in a secure environment. Do not expose the cluster's network interface to the public network. |
Security-mode cluster + HTTPS:
| Such a cluster requires user authentication. It supports access control and data encryption, and it uses HTTPS to encrypt communication and enhance data security. | Use when security takes precedence over performance and public network access is required.
|
Table 2 lists the various types of security mode changes supported for CSS clusters.
Action | Scenario | Change Process |
|---|---|---|
Switching from the non-security mode to security mode | Non-security mode → Security mode + HTTP: Change a cluster from non-security mode to security mode + HTTP. |
|
Non-security mode → Security mode + HTTPS: Change a cluster from non-security mode to security mode + HTTPS. | ||
Switching from the security mode to non-security mode | Security mode → Non-security mode:
| |
Switching between HTTP and HTTPS in security mode | HTTP → HTTPS: Change a cluster from security mode + HTTP to security mode + HTTPS. | |
HTTPS → HTTP: Change a cluster from security mode + HTTPS to security mode + HTTP. |
The security mode settings can be changed only for Elasticsearch clusters created after November 2022 and whose version is 6.5.4 or later.
Before changing the security mode for a cluster, it is essential to assess the potential impacts and review operational recommendations. This enables proper scheduling of the change, minimizing service interruptions.
Action | Service Interruption | Authentication Mode | Performance | Public Network Access | Security Account |
|---|---|---|---|---|---|
Non-security mode → Security mode + HTTP | Yes | Authentication required | N/A | Disallowed | N/A |
Non-security mode → Security mode + HTTPS | Yes | Authentication required | Downgraded | Allowed | N/A |
Security mode → Non-security mode | Yes | Authentication not required | Enhanced | Automatically disabled | Permanently deleted |
HTTP → HTTPS | Yes | No change | Downgraded | Allowed | N/A |
HTTPS → HTTP | Yes | No change | Enhanced | Automatically disabled | N/A |
Impact description:
Changing the security mode for a cluster changes its accessibility mode, possibly causing service interruptions. You should perform this operation before services are brought online or when service interruptions can be tolerated.
The following formula can be used to estimate how long it will take to change the security mode for a cluster:
Change duration (min) = 5 (min) x Total number of nodes to change + Data recovery duration (min)
where,
Data recovery duration (min) = Total data size (MB)/[Total number of vCPUs of the data nodes x 32 (MB/s) x 60 (s)]
where,
You can change a non-security mode cluster to a security-mode cluster that uses HTTP or HTTPS. After a cluster's security mode is enabled, user authentication is required for accessing the cluster.
Figure 1 Enabling the security mode

The Task Status of the cluster is Changing security mode. When the cluster status changes to Available, the security mode has been successfully changed.
You can change a security-mode cluster that uses HTTP or HTTPS to a non-security cluster. After a cluster's security mode is disabled, user authentication is no longer required for accessing the cluster.
Figure 2 Disabling the security mode

The Task Status of the cluster is Changing security mode. When the cluster status changes to Available, the security mode has been successfully changed.
You can change the protocol of a security cluster.
If a public IP address has been assigned to a security-mode cluster, unassign it before changing from HTTPS to HTTP.
Figure 3 Configuring the protocol

HTTPS is used to encrypt cluster communication and you can enable public network access for the cluster.
Cluster communication is no longer encrypted and public network access cannot be enabled.
The Task Status of the cluster is Changing security mode. When the cluster status changes to Available, the security mode has been successfully changed.