Fedora Cloud Product Requirements Document.
About this Document
This PRD (Product Requirements Document) is an evolving document, created by the Fedora Cloud SIG Working Group as part of the process for designing the Fedora Cloud product. The framework for the PRD itself is currently in a draft state.
The actual governance of this document, and whether or not it is “fixed” at a certain point in time or able to evolve (in the form of updating progress, etc.) is still to be determined.
Contributors to this document include:
Reviewers & Contributors
The following people have contributed to the development of this document, through feedback on IRC, mailing lists, and other points of contact.
The Fedora Cloud SIG is one of many teams within the Fedora Project.
The Cloud SIG mailing list is located here.
Minutes and logs from IRC meetings related to the development of this document should be listed here as the document evolves.
Over time, it is expected that this document will undergo various rounds of review, approval, and editing; in the future, it may be rewritten for different releases of Fedora.
While one can review the history of a wiki document (by clicking the "history" tab), it is useful to provide explicit indicators of any major format changes, approvals, or indications of it being in a “final” state, in a list that can allow someone to quickly see that all of the prescribed layers of approval have occured.
- October 28, 2013: Initial Draft of template.
- FutureDate: Approval by SomeGroup; link to any pertinent mail announcement and/or meeting minutes
Tracking of Progress
This document contains numerous descriptions of use cases, descriptions of feature sets to address the use cases, and the requirements to enable those features. Numerous Fedora self-contained and systemwide changess (in addition to updates to individual packages) may combine to address those use cases and feature sets. Thus, as a single release, or even series of releases, undergoes development, it is useful to easily track how an entire use case or feature set may be progressing.
While Fedora uses the Changes Process to track changes in the distribution, those changes are typically described as details of changes to a specific package, or the introduction of a specific package, rather than as a piece of a larger feature set.
This document could possibly be used to do any or a number of the following things:
- Provide a secondary location where changes are tracked (which seems like a lot of overhead to me)
- Provide a location where overall Feature Progress is tracked, via periodic cross-checking against Change pages; this could be either in a standalone section, or simply attached to each Feature description.
- Scope out how features are expected to progress over a number of releases.
- None of these things.
When we more fully determine how to most efficiently track progress, the pointer to where that tracking is done, and/or the description of or process by which we do the tracking is formalized, should be documented in this section in lieu of what is currently written here.
Document Purpose and Overview
What this document describes
This is the Product Requirements Document for the Fedora Cloud SIG.
(A formal definition of a Product Requirements Document can be seen on wikipedia.)
The contents of this document should seek to accomplish the following goals:
- Provide a high-level market of the cloud computing market as it pertains to the Fedora Cloud SIG; this includes overviews of things which may not be within our actual scope/ability to accomplish at the current time.
- Provide deeper understanding of the types of users who could use Fedora for their cloud computing needs. This includes describing their main day-to-day tasks, common problems, etc. The perspective here is not necessarily limited to system administrators, or developers, but a combination of many types of users and roles.
- Ties common issues and needs of potential users/consumers of the Fedora Cloud product to high-level product needs, from a "functional" standpoint
- Provides solutions, in the form of "changes" or "features," which will provide the functionality described as needs for the potential users.
Definitions and Acronyms
- AWS: Amazon Web Services
- Amazon EC2: Amazon Elastic Compute Cloud, a popular public IaaS
- IaaS: Infrastructure as a Service
- PaaS: Platform as a Service
- PRD: Product Requirements Document
- EPEL: Extra Packages for Enterprise Linux
- CI: Continuous Integration
- CD: Continuous Delivery or Continuous Deployment
- SCL: Software Collections
- NTH: Nice-to-have
- BZ: Bugzilla
Indication of prioritization
- Items marked with a ? and following question in italicized lettering are open questions.
Overview of what each section in the PRD (should) contains.
Fedora Cloud provides a customizable base image and tools for developing scale out applications on public and private clouds, as well as a small number of images pre-configured for specific uses.
Public and private cloud adoption is taking off, and the requirements for an image OS differ significantly from the requirements for a desktop or server OS. In these environments, much or all of the instance lifecycle — from the creation of the image and addition of software or configuration specific to the instance, to the teardown of the image — will be automated. Systems are designed to scale out via many identical nodes rather than scale up with carefully-tended individual servers. Individual uptime (mean time between failure) is not as important as the ability to get a new instance running quickly (mean time to recovery).
With that in mind, we're tailoring a release specifically for cloud environments.
Public and private cloud adoption is happening rapidly, but the market is not yet mature and is relatively ripe for disruption even though some favorites have emerged as early leaders.
In the next two to three years, we expect to see a great deal of growth in adoption and still see a number of emerging players where no clear favorites have emerged (for instance, Google Compute Engine).
In short, there's an enormous opportunity for Fedora to become an instance-OS of choice if the project moves quickly, develops or adopts the right technologies, and succeeds in educating the market about its existence. A failure on any of those three points means that the Fedora Cloud product will have little chance in taking a significant portion of the new market or taking any of the existing market.
The Fedora Cloud product consists of an image to be used to run one or more instances in a public cloud, and a set of tools for creating and modifying images. We will also provide two to four additional images that are pre-configured for what we expect to be the most popular scenarios/use cases for using Fedora in public or private cloud.
This consists of:
- AMIs of the Fedora Cloud release on Amazon
- qcow2 images for use with OpenStack
- raw.xz images for use with other IaaS clouds
A limited subset of tools that can be used to generate, modify, and configure Fedora instances for use with public and private clouds.
Major Release Themes
Aside from adoption and development of applications on top of the Fedora Cloud images, we have a few secondary goals that should be helped by wider adoption:
- More testing of Fedora images with additional bug reports.
- Better feedback about how the product should improve. This is separate from "bug reports" in that we hope to engage the audience and receive detailed feedback about use cases, desired features, developing trends in cloud management, etc.
- Patches and contributions that will help improve the product, and Fedora in general. Assuming we're successful, some users should take an interest in helping to develop our product.
Target Market / Audience
Developers creating scale out applications on top of public and private clouds.
How are users going to access the images published by Fedora Cloud? We need to ensure that images are as easy to consume as possible.
Since Fedora Cloud images are meant to be consumed as part of a public or private cloud, we won't be worrying about physical media at all.
Note that the cloud images also won't be "installed" in the same manner that users are accustomed to with desktop or server images. The cloud image will simply boot in its target environment ready to run and/or for further customization/configuration.
Where to obtain
Users will be able to obtain the images for public clouds via download *or* via the usual marketplace for those images. For instance, we publish Amazon AMIs on Amazon directly. Users are able to launch new instances with Fedora without having to obtain the images directly from the Fedora Project and then upload to Amazon.
Users will be able to download appropriate images for Apache CloudStack, Eucalyptus, OpenStack, and other IaaS platforms.
Images will be delivered as AMIs on Amazon EC2, and as downloadable images in qcow2 and raw.xz formats.
Currently, Fedora is not a widely used option for instances on public and private clouds. We know there's some usage, but it's not one of the top three or four OSes on Amazon or (likely) for private clouds.
Success looks like:
- Increase in adoption. We should be able to measure this semi-accurately on Amazon (at least) as the publisher. - Third party support / targeting of Fedora Cloud as a platform. - Increased contribution and participation in the Fedora Cloud WG and Fedora Project in general.
User Profiles, Goals, and Primary Use Cases
Still working out some logic on this section. But forging ahead with what I have for the moment.
Goal of this section is to provide insight into either or both of:
- Primary Use Cases: What are the situations / environments in which we expect a Fedora Cloud Product to be used
- User Profiles and Goals: This is more like “personas” work, or could be done as “user stories” (more along the lines of agile, see http://en.wikipedia.org/wiki/User_story )
... and then ensure that for each type of user or use case, we have features/changes that make the Fedora Cloud product useful.
User Profile #1
- User Goals
What are this user's main goal in using this product?
- Common Tasks
What are the user's main tasks they need to accomplish with the product?
User Profile #2
Primary Use Cases
Fedora Cloud Image on Amazon Web Services (AWS)
- Make Fedora Cloud Image suitable for developers using Amazon EC2 to build and deploy applications on top of.
- Developer is looking for a cloud instance that will have a limited life cycle, and is not concerned about the individual instance (cattle) being fault-tolerant, etc.
- The developer wants to have very recent libraries/applications available.
- Instance will be managed using EC2 tools and configuration management tools like Puppet, Chef, Ansible, etc. and will not be SSH'ing into individual instances to manage them one at a time.
Primary Use Case #2
Secondary Use Cases
Because cloud is “cloudy,” sometimes the cloud product requirements may be dependent on enablement in other Fedora products. Additionally, there may be open source projects with which we desire compatibility.
Note that some of these secondary use cases may overlap with primary use cases. (Or this section may be entirely rolled into that section; TBD.)
Ensure that the Fedora Server product can serve as a platform for the following IaaS projects, or at least that the Fedora Cloud product can be used as a guest/VM/image with those services. For projects that are not currently packaged within Fedora/EPEL, we may need to locate a kind person to ensure testing.
Ensure that fedora cloud image can be used as shipped with Apache cloudstack.Because there is no predefined use of the images on the platform, it should generally be as flexible to run on the platform and provide services as configured. Some of the use cases include:
Mail Servers Web Server and Web application servers Data management servers
It is assumed to support snapshots and templates as is made possible on other platforms.
Fedora should be a useful, productive environment for developers writing code to be executed in a cloud environment.
Simple Deployment of code to from dev to production
As a developer, I want to ensure that my code is easily deployable from my development environment to a production environment, without encountering issues of non-compatibility. Example: A feature described as “Improved deployment of code to a cloud” might be fully described in the Features section, and as a result, Vagrant might be listed as a requirement in the non-functional requirements section, and cross-coordinated with the workstation working group. There are likely numerous other requirements as well.
Development as part of a team
As a member of a development team, I would like to develop in an environment where code can go through unit or functional testing, and be approved or accepted by other members of the team. Example: A feature described as “Continuous Integration platform” may be listed in the Features section, and the various tools available to implement would be enumerated and described in the “non-functional requirements” section, and cross-coordinated with the server working group.
Development using libraries not included in the distribution
As a developer, my toolchain includes libraries or dependencies on other packages using libraries not in the Fedora distribution, and I may be developing for distributions not limited to Fedora.
Example: A feature described as “Portable code” (REALLY POOR DESCRIPTION, sorry) may be listed in the Features section, and “Software Collections” might be listed as a requirement.
Note that this may have some cross-over with a possible additional story/use case, “Deployment of code using libraries not included in the distribution.”
Features here address the primary and secondary use cases, product or secondary objectives, market opportunities from above.
Features should provide functional requirements (“what it should do”) preferably in a narrative fashion - more of a story / solution description, rather than “package XYZ” - the features (the ways to meet a user's objectives?) each likely consist of more than one package/enhancement, and those packages should be detailed in the “Detailed requirements” section of this document, and each of those detailed requirements should refer back to which feature it supports.
Feature description should be described in the line saying “Feature #1/2/etc.”. Describe the feature in more detail, specifically addressing how it addresses user scenarios, primary or secondary use cases / objectives of the product.
Use a table to indicate the following items: Priority (Must, Should, NTH) Citation of use cases addressed
As work continues and specific detailed requirements are developed, reference the detailed requirements within this document helping to fulfill this feature. This helps to ensure awareness around “do we still have a feature if some of the detailed requirements are not fulfilled, and thus are not able to address the specific use case needs / user objectives.”
Supporting packages / work required for the product itself to function to address the use cases above. Non-functional requirements (i.e.: requirements outside the scope of how it actually works / solves problems) are addressed in a later section.
Note that this section does not have to be filled out in detail to the extent that a “Change” would require (per the Changes process in Fedora.)
- Per jwb's mail on 2013-10-30 - questions around kernel requirements need to be addressed at some point, wrt requests for a more minimal kernel for cloud images.
Requirement #1 (Short Description of Requirement)
Refer to which previously described Features, Use Cases this requirement helps to fulfill.
Must, should, NTH
High, Medium, Low
Stakeholders / Owners
Any major dependencies, including things that may require any cross-working-group coordination, should be called out here. Any process changes required within Fedora should be documented here as well.
Level of testing required; is it a blocker to release? Is the testing automate-able?
- Existing BZ:
- Upstream webpage / wiki page / github page(s):
Requirement #2 (Short Description of Requirement)
These are the requirements needed that are not necessarily part of implementation of the product itself, but are still required as part of either making the product more attractive/useful, compatibility requirements for a user's workflow (ie: “works with Puppet,”) or things needing to be done/coordinated in other areas of the project (in other working groups?) to ensure a well-rounded solution.
For each, as was done with Features in a previous section, we should call out some additional information, assuming doing so makes sense for the requirement:
- Priority (Must, Should, NTH)
- Effort required
- Major dependencies / Process Changes needed
- Existing Documentation: BZ #, pointers to upstream project docs
How to create images. Do not be shocked if there are 48 ways to do this. Also: not sure if we want to include containers in this section.
Creation of “official” Fedora Project images
New images. Updated images (ie: providing newer images for a release that have updates already included) might also be included here?
Images created by users
Migration / Upgrades
Fedora Project Documentation
Open Source Projects documentation
Ensuring that Fedora is well-represented, up-to-date in other open source project documentation...
Performance / Scalability / Failover
Virtualization types? Container types?