Optional: Configuring Application Engine with Redis

You can configure your Application Engine installation with Remote Dictionary Server (Redis), which allows you to share session information across multiple nodes in a cluster environment and provides more reliability. The default number of replicas is 2.

1. If it is not already installed, download Redis from http://download.redis.io/releases/ and install.
   Restriction: Access Control Lists for Redis are not supported.
2. To configure Application Engine with Redis, open your custom resource YAML file and make the following updates in the application_engine_configuration section.
   • Set session.use_external_store to true.
   • Update the Redis host, port, and time to live (TTL) in the Redis section.

     redis:
         # Your external Redis host/IP
         host:
         # Your external Redis port
         port: '6379'
         # If your version of Redis enabled TLS connection, set the following parameter to true
         # You should add the Redis server CA certificate in tls_trust_list or trusted_certificate_list
         tls_enabled: false
         # If you are using Redis V6 and later with an username, fill in this field.
         # Otherwise, leave this field empty
         username:
     

   • If Redis is protected by a password, enter it in the REDIS_PASSWORD field in the ae-secret-credential secret that you created in Creating secrets to protect sensitive configuration data.
3. If you want to protect Redis communication with Transport Layer Security (TLS), you have the following options:
   • Sign the Redis certificate with a well-known CA.
   • Sign the Redis certificate with the same root CA that is used by this installation.
   • Use a zero-depth self-signed certificate or sign the certificate with another root CA. See Connecting securetly with external services.
4. To verify the connection to Redis after installation, log in to the Application Engine service that is connected to the Redis instance. If you configured Application Engine with Redis successfully, you can see the session information for any app you create.