diff --git a/doc/03-Configuration.md b/doc/03-Configuration.md
index 9acbe505..5b544d2f 100644
--- a/doc/03-Configuration.md
+++ b/doc/03-Configuration.md
@@ -20,8 +20,42 @@ Connection configuration for the database to which Icinga DB synchronizes monito
 Connection configuration for the Redis® server where Icinga 2 writes check results.
 This data is used to display the latest state information in Icinga DB Web.
 
+You can adjust the Redis® connection settings in the Web UI:
+
 1. Configure the connection to the Redis® server through the `Configuration → Modules → icingadb → Redis` menu.
 
+But you can also do this manually by editing the configuration file `/etc/icingaweb2/modules/icingadb/redis.ini`. The
+basic structure of the file is as follows:
+
+```ini
+[redis]
+
+[redis1]
+
+[redis2]
+```
+
+The `redis` section is used for general options, `redis1` is used for the primary Redis® and `redis2` is used for the
+secondary Redis® in case of high-availability setups. The general options are applied to all Redis® connections.
+
+### Available settings
+
+#### General Redis® Options
+
+| Option | Description                                                                      |
+|--------|----------------------------------------------------------------------------------|
+| tls    | Enable TLS for the connection to Redis®. Set to `1` to enable, or `0` to disable |
+
+#### Primary and Secondary Redis® Options
+
+| Option   | Description                                                                |
+|----------|----------------------------------------------------------------------------|
+| host     | Hostname or IP address of the Redis® server.                               |
+| port     | Port of the Redis® server. Defaults to `6380`.                             |
+| database | Database number to use for the connection. Defaults to `0`.                |
+| username | Username for the Redis® connection. If not set, no authentication is used. |
+| password | Password for the Redis® connection. If not set, no authentication is used. |
+
 !!! info
 
     If you are running a high-availability Icinga 2 setup,