AGENT-1253: Interactive Installation using the Agent Based Installer for Disconnected Environments

enhancements/agent-installer/interactive-installation-using-the-agent-based-installer-for-disconnected-environments.md

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+---
+title: interactive-installation-using-the-agent-based-installer-for-disconnected-environments
+authors:
+  - "@rwsu"
+reviewers: # Include a comment about what domain expertise a reviewer is expected to bring and what area of the enhancement you expect them to focus on. For example: - "@networkguru, for networking aspects, please look at IP bootstrapping aspect"
+  - "@andfasano"
+  - "@bfournie"
+  - "@pawanpinjarkar"
+  - "@danielerez"
+  - "@rawagner"
+approvers: # A single approver is preferred, the role of the approver is to raise important questions, help ensure the enhancement receives reviews from all applicable areas/SMEs, and determine when consensus is achieved such that the EP can move forward to implementation.  Having multiple approvers makes it difficult to determine who is responsible for the actual approval.
+  - "@zaneb"
+api-approvers: # In case of new or modified APIs or API extensions (CRDs, aggregated apiservers, webhooks, finalizers). If there is no API change, use "None"
+  - None
+creation-date: 2025-09-16
+last-updated: 2025-09-16
+tracking-link: # link to the tracking ticket (for example: Jira Feature or Epic ticket) that corresponds to this enhancement
+  - https://issues.redhat.com/browse/VIRTSTRAT-60
+  - https://issues.redhat.com/browse/OCPSTRAT-1874
+  - https://issues.redhat.com/browse/OCPSTRAT-1985
+see-also:
+  - "https://github.com/openshift/enhancements/pull/1821"
+replaces:
+  - 
+superseded-by:
+  -
+---
+
+# Interactive Installation using the Agent Based Installer for Disconnected Environments
+
+## Summary
+
+This enhancement proposes the creation of a streamlined, interactive, and
+UI-driven installation workflow leveraging the Agent Based Installer (ABI) and
+the Assisted Installer service targeted for disconnected environments. The goal
+is to address the complexity of the current installation process, which can
+be challenging for users who are not accustomed to command-line tools and
+manual configuration files. By providing an opinionated, user-friendly UI,
+this initiative aims to simplify cluster setup and reduce the potential for
+errors.
+
+## Motivation
+
+The installation process for a new cluster can be complex, involving multiple
+prerequisites and manual configuration steps that are challenging and
+time-consuming for some users. Customers, especially those accustomed to
+graphical interfaces, often struggle with writing YAML files and ensuring they
+are configured correctly. This proposal seeks to deliver an improved user
+experience by abstracting away this complexity behind a simple, guided UI.
+
+### User Stories
+
+* As an administrator, I want a simple, UI-driven workflow to install a
+cluster, so I can easily set up a new environment without needing to write
+or manage complex YAML configuration files.
+
+* As an administrator deploying a cluster, I want to configure all necessary
+settings, such as networking and topology interactively through a UI, so that
+I can avoid common configuration errors and reduce setup time.
+
+* As an administrator, I want the installer to help me pre-configure and
+install essential operators during cluster setup, so the cluster is ready for
+my workloads immediately after installation.
+
+### Goals
+
+* Provide a user-friendly, UI-driven installation experience in a disconnected
+environment that leverages the existing Agent Based Installer and Assisted
+Installer technologies.
+
+* Simplify the installation process to reduce complexity, especially for users
+who prefer graphical interfaces.
+
+* Allow for the selection and pre-configuration of essential operators as part
+of the installation workflow.
+
+### Non-Goals
+
+* This proposal does not aim to replace existing installation methods but to
+provide a simplified alternative for specific user personas.
+
+* Post-installation cluster management and day-2 operations are out of scope
+for this enhancement.
+
+* Securing the communication between the Assisted Installer UI, Assisted
+Service, and client browsers will be addressed in future updates.
+
+## Proposal
+
+This enhancement proposes extending the functionality of the Agent Based
+Installer to support a fully interactive, UI-based installation flow. The
+core of this proposal is to reuse and adapt the already existing Saas UI and
+tailor it for ABI use cases where a user can install no more than one cluster.
+The UI captures all necessary configuration details from the user, which are 
+then used by Assisted Service to orchestrate the cluster deployment. The UI
+can be used to start an installation from scratch or from a partially
+configured environment.
+
+The UI will be deployed on the rendezvous host as a container using a new image
+to be included in the release payload. A console message will provide users
+with the UI's URL. The UI will collect crucial information to configure the
+cluster and provide host verification to ensure the hardware inventory fulfill
+the cluster topology. It will also check network connectivity between the hosts.
+The workflow will also include a mechanism to select and bundle common
+operators, ensuring they are installed and configured alongside the cluster
+itself.
+
+### Workflow Description
+
+This workflow is activated when the sentinel file, /etc/assisted/interactive-ui,
+is present in the Agent Based Installer ignition.
+
+**cluster creator** is a human user responsible for deploying a cluster.
+
+**Assisted Installer UI** is UI used to configure, initiate, and monitor the
+cluster installation. It is hosted on the rendezvous host.
+
+**rendezvous host** is a host on the cluster that serves the Assisted Service and 
+Assisted installer UI. It also serves as the bootstrap node before it reboots
+during cluster installation to become a member of the cluster.
+
+**OCP console** is the installed cluster's UI.
+
+1. The cluster creator obtains or generates an ISO and boots it on target
+cluster hosts.
+
+2. The URL to the Assisted Installer UI running on a predefined port is
+displayed on the console.
+
+3. On a separate machine the cluster creator opens up the browser to the
+Assisted Installer UI running on the rendezvous host.
+
+4. The cluster creator begins configuring the cluster through the Assisted
+Installer UI, by providing all the required details.
+
+5. If there are no configuration issues, the cluster creator moves to the 
+download credentials screen and downloads files containing the kubeconfig and
+kubeadmin password.
+
+6. Then the Assisted Installer UI shows a confirmation screen showing the 
+configuration that was entered and a list of operators that will be enabled.
+The cluster creator clicks on a button to begin the installation.
+
+7. The Assisted Installer UI shows the installation progress. When the
+installation reaches the point when the rendezvous host is rebooted and will
+join the cluster as a node, the UI will display the URL to the OCP console.
+
+8. When ready, users may access the OCP console.
+
+### API Extensions
+
+There are no changes to APIs.
+
+### Topology Considerations
+
+Will function identically in all topologies.
+
+#### Hypershift / Hosted Control Planes
+
+There are no specific considerations for this feature regarding
+Hypershift / Hosted Control Planes.
+
+#### Standalone Clusters
+
+There are no specific considerations for this feature regarding 
+Standalone Clusters.
+
+#### Single-node Deployments or MicroShift
+
+The same workflow applies to SNO. 
+
+There is no specific considerations for this feature regarding
+MicroShift.
+
+### Implementation Details/Notes/Constraints
+
+No additional details.
+
+### Risks and Mitigations
+
+Communications between the agent running on all nodes and assisted-service
+running on the redenzvous host are currently unsecured. Authentication and
+authorization will need to be added in the future.
+
+### Drawbacks
+
+None.
+
+## Alternatives (Not Implemented)
+
+None.
+
+## Test Plan
+
+The entire installation flow from creation of the boot ISO to initiating the
+install through the Assisted Installer UI and verifying the cluster and
+additional operators have been installed will be included in a e2e test in
+OpenShift CI.
+
+[dev-scripts](https://github.com/openshift-metal3/dev-scripts) will be
+enhanced to test this scenario.
+
+## Graduation Criteria
+
+### Dev Preview -> Tech Preview
+
+- Ability to utilize the enhancement end to end
+- End user documentation
+- Sufficient test coverage
+- Gather feedback from users rather than just developers
+- Integration with the official Red Hat build and release pipeline
+
+### Tech Preview -> GA
+
+- Complete e2e testing for installation.
+- User facing documentation created in [openshift-docs](https://github.com/openshift/openshift-docs/)
+
+### Removing a deprecated feature
+
+Not applicable.
+
+## Upgrade / Downgrade Strategy
+
+Not applicable.
+
+## Version Skew Strategy
+
+Not applicable.
+
+## Operational Aspects of API Extensions
+
+Not applicable.
+
+## Support Procedures
+
+Not applicable.
+