Private Flavors

A user might need a custom flavor that is uniquely tuned for a project she is working on. For example, the user might require 128 GB of memory. If you create a new flavor as described above, the user would have access to the custom flavor, but so would all other tenants in your cloud. Sometimes this sharing isn't desirable. In this scenario, allowing all users to have access to a flavor with 128 GB of memory might cause your cloud to reach full capacity very quickly. To prevent this, you can restrict access to the custom flavor using the nova command:

$ nova flavor-access-add <flavor-id> <project-id>

To view a flavor's access list, do the following:

$ nova flavor-access-list <flavor-id>

Best Practices

Once access to a flavor has been restricted, no other projects besides the ones granted explicit access will be able to see the flavor. This includes the admin project. Make sure to add the admin project in addition to the original project. It's also helpful to allocate a specific numeric range for custom and private flavors. On UNIX-based systems, nonsystem accounts usually have a UID starting at 500. A similar approach can be taken with custom flavors. This helps you easily identify which flavors are custom, private, and public for the entire cloud.