Elasticsearch Authentication
Authenticate to an Elasticsearch cluster using any supported authentication realm that is already configured. This skill
covers all built-in realms, credential verification, and the full API key lifecycle.
For roles, users, role assignment, and role mappings, see the elasticsearch-authz skill.
For detailed API endpoints, see references/api-reference.md.
Deployment note: Not all realms are available on every deployment type. See
Deployment Compatibility for self-managed vs. ECH vs. Serverless details.
Critical principles
- Never ask for credentials in chat. Do not ask the user to paste passwords, API keys, tokens, or any secret into
the conversation. Secrets must not appear in conversation history.
- Always use environment variables. All code examples in this skill reference environment variables (e.g.
ELASTICSEARCH_PASSWORD, ELASTICSEARCH_API_KEY). When a required variable is missing, instruct the user to set it
in a .env file in the project root — never prompt for the value directly.
- Prefer
.env over terminal exports. Agents may run commands in a sandboxed shell session that does not inherit
the user's terminal environment. A .env file in the working directory is reliable across all execution contexts.
Only suggest export as a fallback when the user explicitly prefers it.
Jobs to Be Done
- Authenticate to a cluster using username and password (native realm)
- Connect using an API key (bearer token)
- Verify who is currently authenticated (
_authenticate)
- Choose the right authentication realm for a deployment
- Create an API key with scoped privileges for automation or service access
- Rotate or invalidate an existing API key
- Set up service account tokens for Elastic stack components
- Authenticate with PKI / mutual TLS certificate-based authentication after PKI/TLS setup
- Authenticate with configured external identity providers (SAML, OIDC, LDAP, AD, Kerberos)
- Grant API keys on behalf of other users
Prerequisites
| Item |
Description |
| Elasticsearch URL |
Cluster endpoint (e.g. https://localhost:9200 or a Cloud deployment URL) |
| Credentials |
Depends on the realm — see the methods below |
| Realms configured |
Authentication realms and their identity backends must already be configured (realm chain, IdP, LDAP/AD, Kerberos, PKI/TLS) |
If any required value is missing, instruct the user to add it to a .env file in the project root. Terminal exports may
not be visible to agents running in a separate shell session — the .env file is the reliable default. Never ask the
user to paste credentials into the chat — secrets must not appear in conversation history.
Authentication Realms
Elasticsearch evaluates realms in a configured order (the realm chain). The first realm that can authenticate the
request wins. Internal realms are managed by Elasticsearch; external realms delegate to enterprise identity systems.
Internal realms
Native (username and password)
Users stored in a dedicated Elasticsearch index. Simplest method for interactive use. Managed via Kibana or the user
management APIs (see the elasticsearch-authz skill).
curl -u "${ELASTICSEARCH_USERNAME}:${ELASTICSEARCH_PASSWORD}" "${ELASTICSEARCH_URL}/_security/_authenticate"
File
Users defined in flat files on each cluster node (elasticsearch-users CLI). Always active regardless of license state,
making it the fallback for disaster recovery when paid realms are disabled. Only available on self-managed deployments.
curl -u "${FILE_USER}:${FILE_PASSWORD}" "${ELASTICSEARCH_URL}/_security/_authenticate"
External realms
LDAP
Authenticates against an external LDAP directory using username and password. Self-managed only — not available on ECH
or Serverless. Typically combined with role mappings to translate LDAP groups to Elasticsearch roles.
curl -u "${LDAP_USER}:${LDAP_PASSWORD}" "${ELASTICSEARCH_URL}/_security/_authenticate"
The request is identical to native — Elasticsearch routes it to the LDAP realm via the realm chain.
Active Directory
Authenticates against an Active Directory domain. Self-managed only — not available on ECH or Serverless. Similar to
LDAP but uses AD-specific defaults (user principal name, sAMAccountName). Typically combined with role mappings for AD
group-to-role translation.
curl -u "${AD_USER}:${AD_PASSWORD}" "${ELASTICSEARCH_URL}/_security/_authenticate"
PKI (TLS client certificates)
Authenticates using X.509 client certificates presented during the TLS handshake. Requires a PKI realm and TLS on the
HTTP layer. On ECH, PKI support is limited — check deployment settings. Not available on Serverless. Best for
service-to-service communication in mutual TLS environments.
curl --cert "${CLIENT_CERT}" --key "${CLIENT_KEY}" --cacert "${CA_CERT}" \
"${ELASTICSEARCH_URL}/_security/_authenticate"
SAML
Enables SAML 2.0 Web Browser SSO, primarily for Kibana authentication. On self-managed, configure in
elasticsearch.yml. On ECH, configure through the Cloud deployment settings UI. On Serverless, SAML is handled at the
organization level and not configurable per project. Not usable by standard REST clients — the browser-based redirect
flow is handled by Kibana. Configure another realm (e.g. native or API keys) alongside SAML for programmatic API access.
OIDC (OpenID Connect)
Enables OpenID Connect SSO, primarily for Kibana authentication. On self-managed, configure in elasticsearch.yml. On
ECH, configure through the Cloud deployment settings UI. Not available on Serverless. Like SAML, it relies on browser
redirects and is not suited for direct REST client use. For programmatic access alongside OIDC, use API keys or native
users.
Custom applications can exchange OIDC tokens for Elasticsearch access tokens via POST /_security/oidc/authenticate,
but this requires implementing the full OIDC redirect flow.
JWT (JSON Web Tokens)
Accepts JWTs issued by an external identity provider as bearer tokens. On self-managed, configure in
elasticsearch.yml. On ECH, configure through the Cloud deployment settings UI. Not available on Serverless. Supports
two token types:
id_token (default) — OpenID Connect ID tokens for user-on-behalf-of flows.access_token — OAuth2 client credentials for application identity flows.
curl -H "Authorization: Bearer ${JWT_TOKEN}" "${ELASTICSEARCH_URL}/_security/_authenticate"
Each JWT realm handles one token type. Configure separate realms for id_token and access_token if both are needed.
Kerberos
Authenticates using Kerberos tickets via the SPNEGO mechanism. Self-managed only — not available on ECH or Serverless.
Requires a working KDC infrastructure, proper DNS, and time synchronization.
kinit "${KERBEROS_PRINCIPAL}"
curl --negotiate -u : "${ELASTICSEARCH_URL}/_security/_authenticate"
The --negotiate flag enables SPNEGO. The -u : is required by curl but the username is ignored — the principal from
kinit is used. Requires curl 7.49+ with GSS-API/SPNEGO support.
API keys
Not a realm, but a distinct authentication mechanism. Pass a Base64-encoded API key in the Authorization header.
Preferred for programmatic and automated access.
curl -H "Authorization: ApiKey ${ELASTICSEARCH_API_KEY}" "${ELASTICSEARCH_URL}/_security/_authenticate"
ELASTICSEARCH_API_KEY is the encoded value (Base64 of id:api_key) returned when the key was created.
Verify authentication
Always verify credentials before proceeding:
curl <auth_flags> "${ELASTICSEARCH_URL}/_security/_authenticate"
Check username, roles, and authentication_realm.type to confirm identity and method:
authentication_realm.type |
Realm |
native |
Native |
file |
File |
ldap |
LDAP |
active_directory |
Active Directory |
pki |
PKI |
saml |
SAML |
oidc |
OpenID Connect |
jwt |
JWT |
kerberos |
Kerberos |
For API keys, authentication_type is "api_key" (not a realm type).
Manage API Keys
Create an API key
curl -X POST "${ELASTICSEARCH_URL}/_security/api_key" \
<auth_flags> \
-H "Content-Type: application/json" \
-d '{
"name": "'"${KEY_NAME}"'",
"expiration": "30d",
"role_descriptors": {
"'"${ROLE_NAME}"'": {
"cluster": [],
"indices": [
{
"names": ["'"${INDEX_PATTERN}"'"],
"privileges": ["read"]
}
]
}
}
}'
The response contains id, api_key, and encoded. Store encoded securely — it cannot be retrieved again.
Omit role_descriptors to inherit a snapshot of the authenticated user's current privileges.
Limitation: An API key cannot create another API key with privileges. The derived key is created with no
effective access. Use POST /_security/api_key/grant with user credentials instead.
Get and invalidate API keys
curl "${ELASTICSEARCH_URL}/_security/api_key?name=${KEY_NAME}" <auth_flags>
curl -X DELETE "${ELASTICSEARCH_URL}/_security/api_key" \
<auth_flags> \
-H "Content-Type: application/json" \
-d '{"name": "'"${KEY_NAME}"'"}'
Examples
Create a scoped API key
Request: "Create an API key that can only read from metrics-*."
POST /_security/api_key
{
"name": "metrics-reader-key",
"expiration": "90d",
"role_descriptors": {
"metrics-reader": {
"indices": [
{
"names": ["metrics-*"],
"privileges": ["read", "view_index_metadata"]
}
]
}
}
}
Verify which realm authenticated the user
GET /_security/_authenticate
{
"username": "joe",
"authentication_realm": { "name": "ldap1", "type": "ldap" },
"authentication_type": "realm"
}
Authenticate with a JWT bearer token
curl -H "Authorization: Bearer ${JWT_TOKEN}" "https://my-cluster:9200/_security/_authenticate"
Confirm the response shows authentication_realm.type as "jwt".
Guidelines
Choosing an authentication method
| Method |
Best for |
Trade-offs |
| Native user |
Interactive use, simple setups |
Password must be stored or prompted |
| File user |
Disaster recovery, bootstrap |
Must be configured on every node |
| API key |
Programmatic access, CI/CD, scoped access |
Cannot be retrieved after creation |
| LDAP / AD |
Enterprise directory integration |
Requires network access to directory server |
| PKI certificate |
Service-to-service, mutual TLS environments |
Requires PKI infrastructure and PKI realm |
| SAML |
Kibana SSO via enterprise IdP |
Browser-only; not for REST clients |
| OIDC |
Kibana SSO via OpenID Connect provider |
Browser-only; not for REST clients |
| JWT |
Token-based service and user authentication |
Requires external token issuer and realm config |
| Kerberos |
Windows/enterprise Kerberos environments |
Requires KDC, DNS, time sync infrastructure |
Prefer API keys for automated workflows — they support fine-grained scoping and independent expiration. For Kibana SSO,
use SAML or OIDC. For enterprise directory integration, use LDAP or AD with role mappings (see elasticsearch-au
