If your DCS instances were created a long time ago, the versions of these instances may not be advanced enough to support some new functions (such as backup and restoration). You can contact technical support to upgrade your DCS instances. After the upgrade, you can back up and restore your instances.
Single-node instances do not support the backup function. You can use redis-cli to export RDB files. This operation depends on SYNC command.
redis-cli -h {source_redis_address} -p 6379 [-a password] --rdb {output.rdb}