ECS 3.6.2 Data Access Guide

Retention

The ECS Swift head supports retention of objects to prevent them being deleted or modified for a specified period of time. This is an ECS extension and is not available in the standard Swift API.

Retention can be set in the following ways:

Retention period on object

Stores a retention period with the object. The retention period is set using an x-emc-retention-period header on the object.

Retention policy on object

A retention policy can be set on the object and the period associated with the policy can be set for the namespace. This enables the retention period for a group of objects to be set to the same value using a policy and can be changed for all objects by changing the policy. The use of a policy provides much more flexibility than applying the retention period to an object. In addition, multiple retention policies can be set for a namespace to allow different groups of objects to have different retention periods.

The retention policy applied to an object using an x-emc-retention-policy header on the object and the policy retention period must be set using the ECS Management REST API (or from the ECS Portal).

Retention period on bucket

A retention period stored against a bucket sets a retention period for all objects, with the object level retention period or policy used to provide an object-specific setting where a longer retention is required. The retention period is set using an x-emc-retention-period header on the bucket.

When an attempt is made to modify or delete the object, the larger of the bucket retention period or the object period, set directly on the object or using the object retention policy, is used to determine whether the operation can be performed.