Elasticsearch 決定將基本的安全功能從付費功能轉為免費釋出，很明顯的是受到 Open Distro for Elasticsearch 的壓力而做出的改變：「Security for Elasticsearch is now free」。
要注意的是這不是 open source 版本，只是將這些功能放到 basic tier 裡讓使用者免費使用：
Previously, these core security features required a paid Gold subscription. Now they are free as a part of the Basic tier. Note that our advanced security features — from single sign-on and Active Directory/LDAP authentication to field- and document-level security — remain paid features.
這代表 Open Distro for Elasticsearch 提供的還是比較多：
With Open Distro for Elasticsearch, you can leverage your existing authentication infrastructure such as LDAP/Active Directory, SAML, Kerberos, JSON web tokens, TLS certificates, and Proxy authentication/SSO for user authentication. An internal user repository with support for basic HTTP authentication is also avaliable for easy setup and evaluation.
Granular, role-based access control enables you to control the actions a user can perform on your Elasticsearch cluster. Roles control cluster operations, access to indices, and even the fields and documents users can access. Open Distro for Elasticsearch also supports multi-tenant environments, allowing multiple teams to share the same cluster while only being able to access their team's data and dashboards.
目前看起來還是可以朝 Open Distro for Elasticsearch 靠過去...
