These are the vehicle through which NetApp delivers major features and changes, and are always initially designated FCS. To achieve GA classification, major releases are often replaced by a revision or maintenance release. However, they can become GA if no such additional release is required to achieve the certification for GA.
Major releases are numbered using two digits (such as "3.2"). A release family is the set of releases that have the same feature release denoted by the same first two digits of the release number (e.g. 3.2, 3.2.1, 3.2.2).
Major releases are fully tested by NetApp (as described in the First Customer Ship section above), including tests at selected customer beta sites, before being released.
Maintenance (x.x.x) Release
Maintenance releases are numbered using three digits (such as "3.2.1").
These releases are part of the maintenance release stream for each release family. These are designed to assist customers in validating and gaining stability on the specific release family, and are therefore primarily to deliver bug fixes (as recommended by NetApp Global Services) based on customer impact.
NetApp regularly assesses the stability of the existing release in the field throughout the lifecycle of the release family, and determines whether a maintenance release is needed. If one is necessary it can occur at any time, but no more frequently than every 2 months.
In addition, maintenance releases may be issued for extended platform or OS support. These are never used for major features, but NetApp may under special circumstances add some minor features into maintenance releases.
Maintenance releases are designed to fix multiple customer-impacting bugs. However, if a customer is not experiencing these problems, there is no need to upgrade to the maintenance release.
Maintenance releases are fully tested by NetApp, with specific focus on the bug fixes and other changes, as well as selected regression testing of unchanged features.
So releases between different major releases won't necessarily follow a chronological order