Background
- SIMP-3479Getting issue details... STATUS
Managing Multiple Puppet environments (without SIMP)
Since 2015, control repositories have been the dominant (non-SIMP) technology to manage and deploy Puppet code.
At a high level, this involves:
- A Puppetfile that defines a collection of Puppet modules and where to get them
- A (Git) Control repository, from which each branch defines a complete Puppet environment (including a Puppetfile)
- A tool (r10k or PE Code Manager) to deploy Puppet environments from the control repository
- Deployments are typically triggered by the repository—so that whenever a branch is updated, it is automatically deployed on the Puppet master(s).
The upshot of this is that a control repository branch defines everything needed to recreate a specific Puppet environment.
This makes it simple to:
- Manage multiple Puppet Environments as code:
- Add or remove a branch from the repository to add or remove that environment on the Puppet master
- Test, diff, and review changes like code
- Automate CI pipelines to automatically test and trigger deployments
- Deploy Puppet environments across Puppet architectures that involve multiple masters
- Deploy a specific puppet environment to a remote "agentless" host using Puppet bolt.
Earlier SIMP releases
In earlier SIMP releases (5.0–6.3), it was technically possible to deploy multiple environments from a control repository—but in practice, it was cumbersome and risky:
- Whenever a new Puppet environment was deployed, (manual) follow-on actions were required to ensure the appropriate SIMP data was available for that environment
- RPM updates and
simp_rpm_helper
could modify existing files Puppet and SIMP environment directories - It assumed an in-depth knowledge of Puppet and SIMP
- It still suffered from significant limitations and risks
SIMP 6.4.0: Deploy single environment from a Puppetfile
SIMP 6.4.0 addressed many of tool and RPM-related problems by making Puppetfile-based module deployments the preferred method to deploy modules.
- Puppetfile-based deployment tools like r10k or Code Manager and now preferred to deploy SIMP's Puppet modules
- To prevent conflicts with these tools, SIMP no longer interferes with any files under the Puppet or SIMP environment directories, unless directed to by the user.
- SIMP module RPMs now install tagged versions into local git repositories, for use in local Puppetfiles
- The
simp puppetfile
tool was introduced to automatically generate Puppetfiles based on the current module RPMs.
- The
- The
simp environment new
tool was introduced to help users ensure that corresponding SIMP and Puppet environments are created.
Improvements focused on making it simple to use Puppetfiles in a single environment, with multiple
made it simple to deploy environments, but they didn't make them safe.
During the development of SIMP 6.4.0 it became apparent that the simp environment
workflow would have problems down the road:
- Making a new SIMP writable and secondary environment for ever Puppet environment was arbitrary
- The dependence on
$environment
made it necessary to adopt workarounds like `simp environment new [--copy|--link
]` when environments used the same (or similar) resources - Linked
- The dependence on
- It would be too easy to permanently lose data from linked environments with the proposed
simp environment rm
command