Home > Storage > PowerScale (Isilon) > Product Documentation > Data Protection > Dell PowerScale SmartSync > Base and concrete policies
SmartSync uses a concept of base and concrete policies. The base policy defines a common set of options that apply to concrete policies. The predefined fields are applied from the base policy when a concrete policy is defined. To define a base policy, run the isi dm base-policies create command. To define an associated concrete policy, run isi dm policies create and use the –-base-policy-id option.