InnoDB is one of the storage engines available for MariaDB deployments. From MariaDB 10.2 InnoDB is the default storage engine.
More information about the InnoDB storage engine can be found in the MariaDB Server Documentation.
If there is a requirement to explicitly set the storage engine default this can be done by adding the bel;ow for the [mysqld] section of the MariaDB option file :
default-storage-engine = InnoDB
Note:
Most of these configuration options can be used with the XtraDB storage engine.