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A stable release can be designated as an LTS release based on community agreement and a commitment from a maintainer. The current policy is that each year’s November (X.11) release will be maintained as an LTS for 2 years.

OpenStack

Development

Typical release cycle is 6 months long with two F2F events within every release cycle - Project Teams Gathering and The Forum (around Open Infrastructure Summit). Please keep in mind that openstack is currently reorganizing their release cycle model so information mentioned here may be out of the date or mixed.

The release takes 27 weeks which are numbered as week before the targeted release (R - 1, R - 2 etc). It starts with the identification of community-wide goals and working on specs. The spec is approved by affected project PTL and as soon as it is approved, the implementation can be started. The deadline for adding new specs is R-12. R-7 is the deadline for adding patches with features to the tree. After this point of time only bugfixes are accepted. Last 4 weeks are rc-weeks and are dedicated for testing and bug fixing. More detailed schedule can be found here.

It's also worth to notice that openstack is using lunchpad and storyboard to maintain their progress but not for a strict project management like we do in ONAP.

Maintenance

OpenStack has a well documented maintenance phase.

Basically every release is maintained actively for 18 months. Then the effort is constantly reduced including the reduced CI.