MAC Namespace Specification #

Purpose #

This document defines the deterministic MAC address strategy used across the Deevnet platform, with a primary focus on management-plane workloads.

Deterministic MAC addressing enables:

Stable DHCP reservations
Predictable IP assignments
Reproducible VM rebuilds
Clear mapping between identity layers

Formatting: All MAC addresses must follow the formatting rules in the MAC Address Format Standard (lowercase hex, colon separators).

Guiding Principles #

MAC addresses are generated outside the hypervisor
MACs are explicitly defined in inventory/code
Hypervisors must never auto-generate identity
Identity must survive VM destruction and recreation

Scope #

Workload Type	Policy
Management Plane	Mandatory deterministic MACs
Tenant Workloads	Optional, future-controlled
Ephemeral/Test VMs	May use auto-generated MACs

This specification applies primarily to the management plane.

MAC Address Rules #

Locally Administered Addresses #

All MAC addresses must:

Use a locally administered prefix
Avoid real vendor OUIs

The locally administered bit must be set.

Common valid first octets:

02
06
0A
0E

Namespace Structure #

The MAC namespace is structured to encode environment and role intent.

Format #


02:DD:EE:RR:NN:II

Field	Meaning
`02`	Locally administered prefix
`DD`	Deevnet identifier
`EE`	Environment (dvnt / dvntm)
`RR`	Role identifier
`NN`	Node or service group
`II`	Instance index

Exact hex values are implementation-defined but must remain consistent.

Example Assignments #

Hostname	MAC Address
mgmt-dns-01	02:de:10:01:00:01
mgmt-dhcp-01	02:de:10:02:00:01
mgmt-metrics-01	02:de:10:03:00:01

These values are illustrative; the key requirement is consistency.

Source of Truth #

MAC addresses are stored in:

Inventory
Variable files
Version-controlled repositories

They are never generated dynamically at runtime.

Example inventory snippet:

mgmt_dns_01:
  ansible_host: 192.168.10.10
  mac_address: "02:de:10:01:00:01"

MAC Address Format - Formatting rules (lowercase, colons)
Extended Services - Extended management services architecture and deterministic MAC addressing