jschoubben
84f4425fd6
Two things found by trying to build tier 2. The substrate design asked whether the message broker has to be running before the control plane, and framed it as depending on whether the control plane's own parts talk to each other over it. They do not -- it is one process -- so under that framing the broker stays out of the bundle. The framing cannot answer the question. What decides it is how the control plane reaches a node, and the answer was already decided: only ever over the link, and the link is the broker. So provisioning the broker would require the broker. The first node does not escape this by being local, because it enrols the ordinary way, by dialling the broker at the address in its token -- which was deliberate, and worth keeping. The bundle is two images now. The record says what that costs, including a certificate the broker needs at a moment when there is no mesh to issue one. The language had never been decided for tier 2. Go, for the same reason the host is: the bundle pins this image by digest and runs it where nothing can check it, so the image should hold the program and nothing else. Also corrects something already built: the bootstrap created one database and called it 'mesh'. ADR 0008 grants a context only what it exclusively owns and ADR 0006 says the mesh database names a thing that will not exist. One database per context, so one today, called inventory.
03-DESIGN / 01-to-be
The mesh being built toward. Every statement here traces to a record in
02-DECISIONS/; nothing arrives by drafting.
A document here describes an intention. What currently runs is in
00-as-is/, and the two are never merged — when something ships, the as-is
document is written and this one's status becomes implemented.
| Document | Covers | Rests on |
|---|---|---|
00-work-breakdown.md |
How the decomposition gets built, in what order, and where a human must look | ADR 0001 |
01-end-to-end-testing.md |
The lab: a real mesh a change can be run against before it reaches nodes | ADR 0016, 0029 |
02-scenario-declaration.md |
What a scenario declares — the underlay, and what to place on it | ADR 0016 |
03-scenario-lifecycle.md |
What happens to a scenario — raise, snapshot, restore, move, destroy | ADR 0016 |
04-lab-installation.md |
Getting the lab onto a clean machine, and why it verifies capability rather than installation | ADR 0010 |
05-the-node-host.md |
Tier 0 — the one thing installed by hand, and the only thing that changes a machine | ADR 0005 |
06-the-control-plane.md |
Tier 2 — what the term means, and the test for what belongs in it | ADR 0005 |
07-the-substrate.md |
Tier 1 — what the control plane consumes and cannot grant itself | ADR 0004, 0048 |
08-connectivity.md |
One context in full — overlay, resolution, exposure, filtering, certificates | ADR 0007, 0050, 0051, 0055 |
09-the-node-lifecycle.md |
How a machine becomes a node, stays one, and stops being one | ADR 0004, 0051 |
10-delivery.md |
Modules, the three edges, and how a change becomes a running thing | ADR 0010, 0064, 0065 |
Not yet written
- The remaining six contexts.
ADR 0006
settles the list at seven;
connectivityis the first written in full (08) and the other six do not exist yet. The work breakdown says in what order they are needed. Domain grouping outside the core.Not needed. ADR 0009 is superseded by ADR 0009: there is no domain module to group into, so there is no domain list to settle. Relationships are edges, and grouping is a tag and a query.