Broadcom Exit Strategy: Migration Architecture Framework

Control Plane & Execution Physics Transition Model

Architecture Principle: Migration is a control-plane and execution-physics transition. Relocating the VMDK is the absolute last layer you should move.

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📚 Canonical Architecture References

This repository contains the working models, decision artifacts, and blast-radius maps for ecosystem transitions post-Broadcom.

Want the full risk-deterministic migration framework and SE whiteboard artifacts? 👉 Download the formatted PDF Playbook here

The continuously maintained architectural specifications live here:

1. The Strategic Blueprint: Broadcom Exit Strategy: The Post-Broadcom Migration Architecture
2. The Execution Reality: The Architecture of Migration: Licensing Isn't the Real Risk
3. The Data Physics: Sizing for the CVM: The HCI Controller Tax

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Problem Statement

Platform transitions (e.g., VMware → Nutanix AHV / Sovereign KVM) frequently result in catastrophic Day 2 operational and performance regressions because engineers execute migrations as simple "VM moves."

This ignores two critical system anchors:

1. Control-Plane Coupling: Dependencies on backup APIs, IAM, and monitoring remain tightly coupled to the legacy ESXi hypervisor.
2. Execution Physics: Moving from a centralized SAN to a distributed Hyperconverged Infrastructure (HCI) turns the Top-of-Rack switches into the storage backplane. If you do not account for the CVM tax and scheduler rules, you will encounter "Migration Stutter."

This framework models migration as a dependency graph and an execution translation—not a compute relocation.

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System Model

The Dependency Layer Order (Top → Bottom):

1. Identity / RBAC (Who can authorize)
2. Backup & DR (How we survive failure)
3. Monitoring & Automation (How we observe state)
4. Storage & Network Fabric (Where the data lives and transits)
5. Compute / VMDK (Where the CPU executes)

Migration must proceed in reverse order of compute dependencies (Top to Bottom).

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Failure Signatures

If compute moves before the foundation layers are abstracted:

• The API Break: Recovery gaps emerge because backup controllers cannot talk to the new hypervisor APIs (e.g., missing vCenter hooks).
• The Migration Stutter: I/O spikes during replication/rebuilds saturate the East-West network switches, causing P99 tail latency to stall databases because the new HCI controller tax was ignored.
• The IAM Mismatch: Operational tooling fragments because RBAC policies do not translate 1:1 between vCenter and Prism/KVM.

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Migration Phases

Phase	Objective	Execution
Phase 1	Operational Independence	Decouple monitoring, logging, and metrics from legacy VMware-specific tooling.
Phase 2	Backup Independence	Establish storage-agnostic snapshot and replication paths.
Phase 3	Identity Abstraction	Map AD/Entra groups to the new platform RBAC model (e.g., Nutanix Flow).
Phase 4	Storage I/O Modeling	Calculate write amplification, the CVM Controller Tax, and network buffer requirements.
Phase 5	Compute Relocation	Cutover the CPU/RAM execution state.

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Decision Matrix

Environment	Control-Plane Abstraction	I/O Performance Modeling
Enterprise Production (Monolithic DBs)	✅ Mandatory	✅ Mandatory (Focus: Data Locality & CVM Overhead)
Enterprise Production (Scale-out/Microservices)	✅ Mandatory	✅ Mandatory (Focus: Network Throughput)
Greenfield / Dev Environments	⚠️ Optional	⚠️ Optional
Lab Environments	❌ Not Critical	❌ Not Critical

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Non-Goals

• Product comparisons (UI/UX)
• Vendor endorsements
• Synthetic feature benchmarking

This is a strict control-plane and execution-physics architecture model.

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Support

If this framework clarified your transition strategy and prevented a Day 2 outage, please star the repository.

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