jschoubben
a253afe020
ADR 0032: a scenario is a closed address space. Every segment materialises as its own isolated link belonging to one instance, so two scenarios raised from the same declaration hold the same addresses and never meet. The declaration keeps its literal addresses and they mean what they say — allocating from a pool would have made them a fiction, so a scenario reproducing a specific topology would stop reproducing it. The constraint that follows shapes everything: the lab never reaches into a scenario over IP. It talks to machines through the virtualisation layer's own channel. If it reached them by address, the workstation would need a route into each scenario, and two carrying the same prefix would give it two routes to one destination — failing not with an error but by one scenario's traffic arriving in another. That also makes reachability an honest question. Can this machine reach that one is asked from INSIDE, by executing on the first, rather than probed from a workstation that is not on the network and whose opinion would be a different question with a misleadingly similar answer. The lifecycle itself: six verbs, of which raise and destroy are enough to be useful and the rest are what make repetition cheap. Raising is convergent rather than incremental, because a lab behaving differently from the thing it tests teaches the wrong habit. A failed raise leaves the wreckage standing. Tearing down on failure destroys the only evidence, which is backwards — a scenario that failed to raise is more interesting than one that succeeded. Snapshots are whole-scenario. Per-machine would be cheaper and wrong: the mesh keeps state spanning nodes, so restoring one machine while its peers move on produces a mesh that has never existed, and faults found there would be artefacts of the lab. Closes the declaration's open question about running several scenarios at once.
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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 0015 |
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 0031 |
03-scenario-lifecycle.md |
What happens to a scenario — raise, snapshot, restore, move, destroy | ADR 0032 |
Not yet written
- The eight bounded contexts. ADR 0015 decides the decomposition; the per-context specifications do not exist yet. The work breakdown says in what order they are needed.
- Domain grouping outside the core. ADR 0017 settles the principle and explicitly does not settle the domain list. That is a research effort, not a design document, until it concludes.