You must pass the password authentication when you connect to an ApsaraDB for Redis instance.
You can customize a password when you create an ApsaraDB for Redis instance. You can also set or modify the password of an instance in the ApsaraDB for Redis console after you create the instance. For more information, see Change or reset the password.
If an ApsaraDB for Redis instance with local disks that resides within a virtual private cloud (VPC) is an instance of Community Edition or a performance-enhanced instance of Enhanced Edition (Tair), or if an instance resides within a VPC is a persistent memory-optimized instance of Enhanced Edition (Tair), you can enable password-free access for the instance to allow the instance to be connected without using passwords. For more information, see Enable password-free access.