authentik/website/docs/core/architecture.md

title
Architecture

authentik consists of a handful of components, most of which are required for a functioning setup.

graph LR
    user(User) --> ak_server(authentik Server)
    ak_server --> ak_server_core(authentik Server Core)
    ak_server --> ak_outpost(Embedded outpost)
    ak_server_core --> db(PostgreSQL)
    ak_server_core --> cache(Redis)
    ak_worker(Background Worker) --> db(PostgreSQL)
    ak_worker(Background Worker) --> cache(Redis)

Server

The server container consists of two sub-components, the actual server itself and the embedded outpost. Incoming requests to the server container(s) are routed by a lightweight router to either the Core server or the embedded outpost. This router also handles requests for any static assets such as JavaScript and CSS files.

Core

The core sub-component handles most of authentik's logic, such as API requests, flow executions, any kind of SSO requests, etc.

Embedded outpost

Similar to other outposts, this outpost allows using Proxy providers without deploying a separate outpost.

Persistence

• /data/media is used to store icons and such, but not required, and if not mounted, authentik will allow you to set a URL to icons in place of a file upload

Background Worker

This container executes background tasks, such as sending emails, the event notification system, and everything you can see on the System Tasks page in the frontend.

Persistence

• /data/certs is used for authentik to import external certs, which in most cases shouldn't be used for SAML, but rather if you use authentik without a reverse proxy, this can be used for example for the Let's Encrypt integration
• /data/email-templates is used for custom email templates, and as with the other ones fully optional

PostgreSQL

authentik uses PostgreSQL to store all of its configuration and other data (excluding uploaded files).

Persistence

• /var/lib/postgresql/data is used to store the PostgreSQL database

On Kubernetes, with the default Helm chart and using the packaged PostgreSQL sub-chart, persistent data is stored in a PVC.

Redis

authentik uses Redis as a message-queue and a cache. Data in Redis is not required to be persistent, however you should be aware that restarting Redis will cause the loss of all sessions.

Persistence

• /data is used to store the Redis data

On Kubernetes, with the default Helm chart and using the packaged Redis sub-chart, persistent data is stored in a PVC.