(Optional) Add a realm configuration of type file to elasticsearch.yml under the xpack.security.authc.realms namespace. At a minimum, you must set the realm type to file. If you are configuring multiple realms, you should also explicitly set the order attribute.

For example, the following snippet shows a file realm configuration that sets the order to zero so the realm is checked first:

xpack:
  security:
    authc:
      realms:
        file1:
          type: file
          order: 0

Add user information to the ES_PATH_CONF/users file on each node in the cluster.

The users file stores all the users and their passwords. Each line in the file represents a single user entry consisting of the username and hashed and salted password.

rdeniro:$2a$10$BBJ/ILiyJ1eBTYoRKxkqbuDEdYECplvxnqQ47uiowE7yGqvCEgj9W
alpacino:$2a$10$cNwHnElYiMYZ/T3K4PvzGeJ1KbpXZp2PfoQD.gfaVdImnHOwIuBKS
jacknich:{PBKDF2}50000$z1CLJt0MEFjkIK5iEfgvfnA6xq7lF25uasspsTKSo5Q=$XxCVLbaKDimOdyWgLCLJiyoiWpA/XDMe/xtVgn1r5Sg=

To limit exposure to credential theft and mitigate credential compromise, the file realm stores passwords and caches user credentials according to security best practices. By default, a hashed version of user credentials is stored in memory, using a salted sha-256 hash algorithm and a hashed version of passwords is stored on disk salted and hashed with the bcrypt hash algorithm. To use different hash algorithms, see User cache and password hash algorithmsedit.

While it is possible to modify the users files directly using any standard text editor, we strongly recommend using the elasticsearch-users tool to apply the required changes.

As the administrator of the cluster, it is your responsibility to ensure the same users are defined on every node in the cluster. The Elasticsearch security features do not deliver any mechanisms to guarantee this.

Add role information to the ES_PATH_CONF/users_roles file on each node in the cluster.

The users_roles file stores the roles associated with the users. For example:

admin:rdeniro
power_user:alpacino,jacknich
user:jacknich

Each row maps a role to a comma-separated list of all the users that are associated with that role.

You can use the elasticsearch-users tool to update this file. You must ensure that the same changes are made on every node in the cluster.

(Optional) Change how often the users and users_roles files are checked.

By default, Elasticsearch checks these files for changes every 5 seconds. You can change this default behavior by changing the resource.reload.interval.high setting in the elasticsearch.yml file (as this is a common setting in Elasticsearch, changing its value may effect other schedules in the system).