Bug 1566765

Description of problem:
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Many users are regularly modifying the following on their existing Content Hosts:
  -Enabled repositories
  -Content View
  -Lifecycle Environment
  -Release Version
  -Attached Subscriptions
  -etc.

Instead of setting these using the WebUI/API/Hammer/cli, what they usually do is that they update their Activation Key (or create a new one) and then proceed with a massive bulk client re-registration (as the Activation Key only takes effect at that time). This is usually done with their configuration management tool running on the clients (puppet, ansible, chef, etc).

Doing massive re-registration on a regular basis will often cause some issue within Satellite and will be more and more demanding as new systems are added over time. Usually this is causing different collateral symptoms (paused tasks, too many tasks, high load, registration time out, other tasks not been processed, inconsistency between candlepin and foreman, etc).


Suggested improvement/feature:
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A. Provide a way to leverage the current Activation Key solution (single point of configuration) without having to re-register the clients.

B. Develop a new feature that allows users to configure as many settings as the Activation Key to maintain existing clients and future clients to be provisioned, which would be easy to use with configuration management tool by having a single variable to use.


Benefits:
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Avoid massive re-registration and related issues with this practice.
Simplify automation for users.