Compare commits

..
Author SHA1 Message Date
jschoubben 68650cda5f Issue 191: an internal name is served to the private network only
The first fix served the dropped route to anyone who sent its name. Record
why in the issue, as a progressive insight on ADR 0138, and in the to-be
connectivity design.
2026-10-02 01:10:13 +02:00
jschoubben 496d136d72 Issue 191: a route with only an internal name is dropped as naming nothing 2026-10-01 23:31:57 +02:00
9 changed files with 160 additions and 483 deletions
@@ -124,6 +124,30 @@ This corrects a fact, not the decision: one statement per endpoint, three things
none of them deciding on its own, all stand. The table in the decision should be read with the filter
column applying to an unrouted endpoint.
## Progressive insight — 2026-10-02, from issue 191
**For a routed endpoint, "the proxy serves the internal name" has to mean "serves it to the private
network", and only the proxy can make it mean that.** The decision says `internal` means the proxy
serves the internal name and not the public one. It does not say to whom, and the proxy answered
every name it routes to any request that carried it, on the same listeners as its public names. A
name being internal kept nobody out: a request from the internet only had to send it. While every
routed endpoint also had a public name, nothing showed it. Once an endpoint could be internal alone
([issue 191](../04-ISSUES/191-a-route-with-only-an-internal-name-is-dropped/00-report.md)), serving
its name to everyone would have published exactly what `internal` was chosen to keep private.
The earlier insight above says the port is not the path for a routed endpoint. This is its other
half: the proxy is the path, so the proxy is where `internal` is enforced. It serves an internal name
only to a request from the private network — the mesh's range, the machine itself, or one of its own
container networks ([ADR 0144](0144-anything-on-a-machine-may-call-anything-on-it.md)). To anyone else, the name is
answered as one never routed, in the handshake and in the request, and not listed among the names it
serves. This holds for the internal name of a `both` endpoint too, whose outsiders have its public
name.
The decision, the options and the consequences stand: one statement per endpoint, three things
derived from it. Checked in the proxy's own tests: an internal-only name is served to the mesh
range, to loopback and to a container bridge, and refused, unlisted and uncertified for a request
from outside; with no range given, it is served to the machine alone.
## Consequences
- **A manifest gains endpoint names, and a route contribution names an endpoint instead of a port.**
@@ -1,135 +0,0 @@
---
topic: what runs on it
status: proposed
date: 2026-10-01
deciders: jochen
reconstructed: false
extends: 02-DECISIONS/0046-a-module-configuration-is-its-assignments-not-its-manifest.md
---
# 164. A setting is declared with its default, its meaning and what changing it costs
## Context
The operator asked for one thing for every module, with the container runtime as the first case: **one
consistent default configuration for every machine, overridable per assignment, and easy to change
later.** The four machines' runtime configurations were each written by hand and differ — one keeps
running containers through a daemon restart and one does not, their log rotation differs, and each
names its resolver and its trusted registries in its own words.
Most of this was already decided.
[ADR 0046](0046-a-module-configuration-is-its-assignments-not-its-manifest.md) said the definition is
identity and **defaults**, the assignment's settings are the configuration, *unset is the default*, and
*an unknown setting is refused*. [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md) made
a setting an operator requirement whose contract is "a type and, optionally, a default", answered by
"the assignment's, or the requirement's default, or unresolved". An assignment is a module on a node,
so the node layer of a module's settings already *is* the per-assignment override, and the mesh-wide
layer is the one consistent default a person changes once.
What was built is narrower than what was decided, measured in the controller on the day of deciding:
- **Nothing declares which keys are settable.** A mergeable file's content is its defaults, and every
key of it — and every key not in it — is accepted. Nothing tells a person, or the console, what can be
set, of what type, or what it means.
- **The refusal of an unknown setting is not there for most modules.** The stray-setting report returns
nothing at all for a module with any mergeable file, because such a file "takes any key"
([issue 173](../04-ISSUES/173-a-modules-settings-reach-every-fact-it-contributes/00-report.md) left
files that way on purpose). It reports rather than refuses where it does run.
- **A value in a file that is not JSON can have no default.** `${setting:<key>}`
([ADR 0155](0155-a-definition-names-no-installation-and-how-that-is-checked.md)) is refused when no
layer sets it — right for a mail domain, where a default is the very literal 0155 removes, and wrong
for a tunable like the resolver's upstreams, which the resolver module therefore carries as literals
in its file.
- **What a change costs is said per file, not per key.** A service names the files it is reloaded or
restarted on. The runtime re-reads its trusted registries on a reload and its `dns` key only when it
starts; the resolver module declared a reload, so on two machines the key was written, reloaded,
and never read, and every container got a public resolver for weeks while everything read as
current ([issue 110](../04-ISSUES/110-a-container-on-the-runtimes-own-network-cannot-reach-the-resolver/01-resolution.md)).
## Considered Options
1. **Leave settings implicit; document each module's keys in its README.** Rejected: a key the mesh
does not know cannot be refused, typed, listed by the console or costed, and a README is a rule
enforced by nothing.
2. **A second mechanism for tunables beside settings** — defaults in a new block, settings untouched.
Rejected: two ways to state one person's value, and design 27 already retires six mechanisms
that grew that way.
3. **Settings declared in the definition, as 0112's operator requirement: a key, a type, a meaning,
optionally a default, and what a change costs.** Adopted.
## Decision
**A module declares every setting it takes.** Each declared setting has a name, a type, one sentence
of meaning, optionally a default, and what a change to it costs. The spelling is design 27's to settle
with the rest of the requirement form; this record decides the content.
**A setting with a default is a tunable; a setting without one is the operator's.** A tunable resolves
to its default when no layer sets it — wherever it is read, a mergeable file or `${setting:<key>}` in a
file of any format. A setting with no default is refused by name when nothing sets it, as 0155 decided;
0155's refusal is narrowed to exactly that case, not changed for it. Whether a value has a default is a
fact about the software (a log size does, a mail domain does not), and the definition states it once.
**The layers stay as they are, and every value says where it came from.** The definition's default,
then the mesh-wide layer, then the node's — later wins, objects merge, lists replace. One consistent
configuration for every machine is the default plus the mesh-wide layer; one machine that differs says
so in its own layer and nothing else. Asked for a module's configuration on a machine, the mesh lists
every declared setting with its effective value and its source: *default*, *mesh*, or *node*.
**Changing later is changing one of three places, and the plan shows its reach before anything moves.**
A new default ships with the module's next version and reaches every assignment that does not override
it; a mesh-wide setting reaches every assignment of the module; a node's reaches one. The plan of a
change names each assignment whose effective value moves.
**A declared setting is the only kind accepted.** Setting a key the module does not declare is refused
when it is set, naming the declared keys, rather than reported when the machine is planned. The mesh's
own words — where a port, a directory or an operator's data is placed, how far an endpoint reaches —
are the mesh's to validate as they are today, and no module declares them. A module
that declares no settings keeps today's behaviour until it does; a catalogue test lists those modules,
and the list shrinks to empty before the implicit form is removed — design 27's rule for every retired
mechanism.
**A setting says what it costs: nothing, a reload, or a restart.** When a file changes, the host
applies the strongest cost among the settings whose values moved in it, so a key the software reads
only at start can no longer be written and never read. A setting that reaches a container's environment
costs that container being recreated, which the host already does when a container's specification
changes; it needs no declaration. A service's `reload-on` and `restart-on` keep
naming the files that are not settings — a generated roster, a credential.
**The container runtime is the first module to declare its settings** and the model for the rest:
its log rotation, keeping containers through a daemon restart, and its resolver are tunables, and
its trusted registries are what the mesh tells it.
## Consequences
- The console can show a module's settings as a form: what can be set, of what type, its default,
and where the current value came from. That is the surface the operator wants for changing a
default later.
- `settings set` can refuse an unknown key, so ADR 0046's rule is enforced where it was only stated.
- The resolver's upstreams, the runtime's log rotation, and other literals a definition carries
because it could not give them a default become declared tunables.
- **What got harder:** every module that takes settings must list them, and a mergeable file no
longer silently accepts a key its author did not foresee. A person who needs one adds it to the
definition, which is a new module version, not a setting.
- Issue 173's open question — a consumer checks nothing against a contract — is unchanged; this record
is the operator half of design 27's contract, not the provider half.
- Not decided here: the spelling (design 27); whether a node's layer may be narrowed to a single key
rather than replaced whole, as `settings set` does today.
## How this is checked
| Rule | Checked by |
|---|---|
| Every setting a module takes is declared | A parser test refusing a setting declaration without a type or meaning; a catalogue test listing modules with mergeable files or `${setting:}` and no declarations, which must be empty before the implicit form is removed |
| A tunable resolves to its default; an operator value without one is refused | Resolution tests: an unset tunable in a JSON file and in a text file both take the default; an unset setting with no default is refused naming it (0155's existing test) |
| An undeclared key is refused when set | A controller test: `settings set` with an undeclared key fails naming the declared keys, and nothing is stored |
| Every effective value names its source | A test listing a module's configuration on a node with one key from each of default, mesh and node |
| A change's reach is shown before it moves | A plan test: changing a mesh-wide setting names every assignment whose effective value moves and no other |
| The strongest cost applies | A host test: a file where a reload-cost key and a restart-cost key both moved restarts; a file where only reload-cost keys moved reloads |
| Live | The container runtime's module lists its settings with their sources on every machine, and a mesh-wide change to its log rotation reaches all four at the next push |
## References
- [ADR 0046](0046-a-module-configuration-is-its-assignments-not-its-manifest.md), [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md), [ADR 0155](0155-a-definition-names-no-installation-and-how-that-is-checked.md), [ADR 0102](0102-the-mesh-writes-into-a-shared-file-never-over-it.md)
- [Design 27 — a module requires, the mesh resolves](../03-DESIGN/01-to-be/27-a-module-requires-the-mesh-resolves.md)
- Issues [110](../04-ISSUES/110-a-container-on-the-runtimes-own-network-cannot-reach-the-resolver/00-report.md), [173](../04-ISSUES/173-a-modules-settings-reach-every-fact-it-contributes/00-report.md)
- mesh-controller `internal/catalogue/settings.go` (`settle`, `UnusedSettings`), `internal/catalogue/setting_into.go`
@@ -1,105 +0,0 @@
---
topic: what runs on it
status: proposed
date: 2026-10-01
deciders: jochen
reconstructed: false
extends: 02-DECISIONS/0161-what-deserves-a-seat.md
---
# 165. `container-runtime` is what a machine can run; that a runtime is running is its holder's health
## Context
A capability is a requirement a module places on a machine, detected by the host and renewed with
every report ([ADR 0161](0161-what-deserves-a-seat.md)). The host's `container-runtime` asks the
daemon for its version: *a running daemon, not an installed client*. It was made that way by
[issue 007](../04-ISSUES/007-an-installed-package-is-not-a-capability/00-report.md), where an
installed package was believed to be a working service, and
[design 05](../03-DESIGN/01-to-be/05-the-node-host.md)'s table says the same: *a runtime is
running*. The installer's preflight borrows the same detector to wait for the runtime the
foundation bundle installs, so there is one answer to "is there a runtime here".
The mesh is now to have a module for the runtime itself — its packages, its configuration, its
service — on every machine ([ADR 0166](0166-the-container-runtime-is-a-node-seat-and-the-host-creates-containers-through-its-holder.md)).
That module cannot declare `container-runtime` as defined: it would require the very thing it
installs, the cycle [research 011](../01-RESEARCH/011-the-module-graph/cases.md)'s case 12 names
("something the mesh installs that then becomes a node capability"). The operator defined the word
for it: **`container-runtime` means the machine is able, at the kernel level, to install a runtime and
execute containers** — not that one is installed, and not that one is running.
The host already draws this line once. `seat` is hardware, a display server *could* run here;
`graphical-session` is state, one *is* running; the detector's own comment says "assignment needs the
first". A machine without a display has no seat however much software is installed, and a machine
with one has a seat before anything is.
Fifty-four catalogue modules declare `container-runtime` today, counted on the catalogue's main
branch on the day of deciding: every module that delivers a container. Each relies on the current
meaning to keep it off a machine with no running runtime.
## Considered Options
1. **Keep the meaning; let the runtime's module declare nothing.** Rejected: a module that installs
the runtime has requirements on the machine — the kernel features without which installing it is
pointless — and would state none of them. The cycle stays, only hidden.
2. **Two capabilities, "can run" and "is running".** Rejected: the second is made true by assigning a
module, so it is the module's state, not a fact of the machine; a capability the mesh itself
flips by its own assignment is case 12's cycle with an extra name.
3. **The capability is the kernel's; whether a runtime runs is the runtime module's health, and a
module that delivers a container needs the runtime's seat held.** Adopted.
## Decision
**`container-runtime` is detected from what the kernel offers**, as `seat` is: the namespaces a
container needs, a control-group hierarchy the runtime can manage, and an overlay filesystem the
running kernel has or can load. Present when all three are; absent naming the missing one. Nothing is
run and no runtime is asked. The verdict's detail names what was found, not a runtime's version.
**"A runtime is running and answers" is one probe, owned by the host and used twice:** by the
installer's preflight, which waits for the runtime the foundation installs, and as the runtime
module's health. It asks the daemon, as issue 007 requires. The preflight stops borrowing the
capability's detector, and there is still one answer to "is a runtime running here".
**The runtime's module declares `container-runtime`**, with `package-manager`, `service-manager` and
`privileged`, like any module that manages machine software.
**A module that delivers a container needs the runtime seat held on its machine**, and is refused
otherwise, naming the seat and the modules that could hold it — the refusal design 27 already lists
for an unheld seat. That requirement is derived from the container resource and needs no manifest
field ([ADR 0166](0166-the-container-runtime-is-a-node-seat-and-the-host-creates-containers-through-its-holder.md)).
The fifty-four existing declarations of the capability stay valid and become redundant; a catalogue
test lists them, and they retire when the list is empty.
**The order is fixed, not preferred.** The detector changes only once the seat requirement is
enforced. In between, a machine with the kernel and no running runtime would read as able to run
every containerised module, which is issue 007 again.
## Consequences
- Design 05's capability table changes its `container-runtime` row from *a runtime is running* to
*the kernel can run containers*, and names the runtime module's health as where "running" is now
asked.
- The node listing stops showing the runtime's version beside the capability. The version moves to
the runtime module's health and its seat's verbs.
- A fresh machine with no runtime reads as able to run one, so it can be assigned the runtime's
module, which is what makes the mesh able to install the runtime instead of the bootstrap alone.
- **What got harder:** "is this machine running containers" is no longer one glance at the profile;
it is the runtime seat's holder and its health. The node's listing should show both side by side.
## How this is checked
| Rule | Checked by |
|---|---|
| The capability is the kernel's | Host detector tests over a fixture `/proc` and `/sys`: all three present → present; each one missing → absent naming it; no runtime binary on the fixture machine changes nothing |
| One probe asks whether a runtime runs | A host test that the preflight and the runtime module's health call the same probe, and that the probe fails against a stopped daemon with an installed client (issue 007's shape) |
| A containerised module needs the runtime seat held | A resolution test: a module with a container resource on a machine whose runtime seat is unheld is refused, naming the seat and its candidate holders |
| The order holds | The host release that changes the detector is gated on the controller release that enforces the seat requirement — stated in both changes' descriptions and checked at review |
| Live | Every machine's profile shows `container-runtime` present with the kernel's features as its detail; a machine with no runtime installed reads present too |
## References
- [ADR 0161](0161-what-deserves-a-seat.md) — the profile renewed by every report; a capability that names a dialect
- [ADR 0166](0166-the-container-runtime-is-a-node-seat-and-the-host-creates-containers-through-its-holder.md) — the seat and its holder
- [Issue 007](../04-ISSUES/007-an-installed-package-is-not-a-capability/00-report.md), [research 011](../01-RESEARCH/011-the-module-graph/cases.md) cases 12–13
- [Design 05 — the node host](../03-DESIGN/01-to-be/05-the-node-host.md)
- mesh-host `internal/profile/detectors.go` (the runtime detector), `internal/profile/seat.go` (the hardware/state split), `internal/bootstrap/preflight.go` (the preflight that borrows it)
@@ -1,161 +0,0 @@
---
topic: what runs on it
status: proposed
date: 2026-10-01
deciders: jochen
reconstructed: false
extends: 02-DECISIONS/0161-what-deserves-a-seat.md
---
# 166. The container runtime is a node seat, and the host creates containers through its holder
## Context
Every container the mesh runs on a machine is created by the host, which looks for a runtime
(`docker info`, then `podman info`) and drives that runtime's command line itself: run, inspect,
remove, exec. Research 012 called this "detected rather than declared": the host takes over whatever
runtime it finds. Nothing in the mesh owns the runtime. Its package came from the foundation bundle
or was already on the machine. Its configuration file was written by hand, differs on each of the
four machines, and is also written into by two modules that are not the runtime's
([issue 190](../04-ISSUES/190-the-runtimes-configuration-is-written-by-modules-that-are-not-the-runtime/00-report.md)).
Its service is declared by those same two.
The operator set the direction:
- a module for the runtime, on every machine, owning "what is needed to run containers here": its
packages, its configuration and its service;
- that module holds a node seat for the runtime, so a second runtime (podman) can later compete
for the seat;
- the host stops speaking to the runtime directly and uses the seat's holder. The host stays the one
that decides, and the holder becomes the one that executes;
- every container on the machine is in scope, not only the mesh's. A development environment started
by hand, or a test database a tool runs, is legitimate. The host already calls these *strays*: 3,
8 and 25 on three of the machines on the day of deciding;
- the runtime's events and verbs are subjects on the bus, and the mesh's own interface is built on
them. The third-party interface run until now was removed by hand.
[ADR 0161](0161-what-deserves-a-seat.md)'s test for a seat is whether the mesh's own code finds it by
name. Here it does: the host would look up the holder on its own machine. A singular role of a module
held once per machine is a `node-*` seat ([ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md)),
in the controller's seed.
The constraint that decides most of this record is a cycle. The bus runs in containers. On the
broker's machine, the broker's own container is created by the host. A holder's code served from a
container cannot create the container that runs it. On a first machine, before the controller exists,
nothing holds anything.
## Considered Options
1. **The host calls the holder's verbs over the bus.** Rejected: with the broker down, no machine can
create any container, including the broker's. The mesh would be unable to restart its own
transport.
2. **The holder picks a dialect that the host speaks itself, as with the uplink.** Rejected: the
host would still drive the runtime, and the module would drive it too for every other caller.
That is two programs speaking to one daemon, and they come to disagree about the same machine
(the installer's preflight already exists to avoid this).
3. **The holder's code runs as a supervised process on the machine and serves the seat's verbs
twice: locally to the host, on the bus to everyone else.** Adopted.
## Decision
**`node-container-runtime` is a seat of the mesh's own, node-scoped,** in the controller's seed under
this record. It delivers no provision; what it carries is its role's protocol: verbs its holder must
serve ([ADR 0132](0132-a-seat-carries-the-tools-its-holder-must-serve.md)) and events its holder emits
([ADR 0129](0129-a-seat-carries-the-protocol-of-its-role.md)). The runtime's module, `docker`, claims
it and is assigned to every machine. A podman module may claim it later; one machine runs one.
**The seat's verbs cover every container on the machine:** list, inspect, logs, stats, start, stop,
restart, create and remove. A mesh-held container is marked by the host's label and says which
assignment holds it. **A container the runtime runs can be root on the machine** — privileged, a host
path mounted, the host's network or process namespace, the runtime's own socket — so a caller other
than the host may not create one that is any of these; only a declaration the mesh composed may ask
for them. And the verbs that change anything are granted by name, never by a wildcard: a grant of
every tool (the console's today) reaches the reading verbs only. Issue 193 is what a verb that trusts
its caller costs. **Creating or removing a mesh-held container is the host's alone.** Any other
caller is refused naming the assignment, because the host would undo it at its next apply. Starting,
stopping or restarting one is allowed, and the answer says the host will restore what its
declaration says. A container the mesh does not hold is the caller's to do anything with.
**The seat's events are the runtime's own** — a container created, started, stopped, died, removed,
its health changed. They are emitted on the seat's subjects, so every holder emits the same events and
no reader depends on which runtime holds the seat. As
[ADR 0160](0160-the-mesh-issues-an-assignments-subjects-and-a-runtime-serves-what-it-is-issued.md)
decides, the subjects are issued by the controller, not composed by the module.
**The holder's code is a supervised process, not a container** ([ADR 0150](0150-a-modules-own-code-runs-as-supervised-processes-under-one-account.md)).
A runtime cannot be run by the thing it runs. The process serves the seat's verbs on the bus to the
console, to tools and to the mesh's interface. The same verbs are served on a local socket on the
machine, which only the host may use. **The host creates, inspects and removes its containers
through that socket and nothing else.** If the holder does not answer, the host creates nothing. It
says so in its report, naming the seat. It never falls back to the command line.
**A container needs the seat held on its machine.** An assignment that delivers a container on a
machine whose runtime seat is unheld is refused, naming the seat and its candidates
([ADR 0165](0165-container-runtime-is-what-a-machine-can-run-and-a-running-runtime-is-its-holders-health.md)).
Mounting the runtime's socket into a container is granted by the seat, not by the capability. The
socket's path is the holder's to state, because podman's is not docker's.
**The runtime module owns the runtime's configuration.** Its settings are declared with defaults
([ADR 0164](0164-a-setting-is-declared-with-its-default-its-meaning-and-what-changing-it-costs.md)):
the resolver containers use, the registries it trusts, log rotation, and keeping containers through a
daemon restart. The module is given the resolver's address and the mesh's registry as values; no other
module writes the runtime's file or declares its service.
**The first machine is bootstrapped with the holder, and adopted afterwards.** The foundation bundle
already installs the runtime's package and service. It also carries the holder's process, delivered as
a binary the way the host is ([ADR 0142](0142-the-mesh-delivers-its-own-components-as-binaries.md)).
When the runtime module is assigned, it adopts what the bundle made, as the store and broker modules
adopt theirs ([ADR 0078](0078-the-store-and-broker-are-modules.md)).
## Consequences
- **The migration on the running mesh has a fixed order:**
1. Each machine's hand-written configuration is read, because the module's defaults replace what
differs.
2. In one push per machine: the resolver module and the private network stop writing the
runtime's file ([issue 190](../04-ISSUES/190-the-runtimes-configuration-is-written-by-modules-that-are-not-the-runtime/00-report.md)),
and the runtime module is assigned and adopts the runtime, its file and its service. Split in
two, either the controller refuses two modules declaring one path, or a machine is left with
nothing setting `dns` and `live-restore`.
3. The controller seeds the seat and enforces the container requirement.
4. The host releases the version that uses the holder.
5. The host's command-line path is removed in the release after every machine's holder answers.
Until then, the host reports per machine which path it used.
- **Every container the host makes depends on the holder's process.** A crash-looping holder stops
new containers on its machine. Running containers are unaffected. The host's report names the cause.
- The process form of a module's own code must serve tools on the live mesh before this ships. Only the
showcase declares it, and [issue 117](../04-ISSUES/117-a-modules-own-code-is-a-container-and-a-process/01-diagnosis.md)
found the showcase's tools declared in a form nothing runs. The runtime module is the first whose
tools cannot fall back to a container.
- A user interface subscribing to events directly does not exist. Today a reader of events is a module
that consumes them. The mesh's container view is a module, or waits for that path.
- [ADR 0005](0005-the-node-host.md) ("a container runtime is detected, not chosen") and
[ADR 0006](0006-the-substrate-and-the-control-plane.md)'s matching line describe the mechanism this replaces: on
acceptance, each gets a dated note saying the runtime is now a seat's holder, as the decision
records' rule for a moved mechanism requires. Design 05 and design 26 are amended after acceptance.
- The operator's decision to remove the third-party interface by hand needs no mechanism. No
module-retires-module rule is introduced.
- **What got harder:** the host gains a dependency it did not have, and a first machine's bundle gains
a component. The direct path was simpler and is what makes a runtime a black box to the rest of the
mesh.
## How this is checked
| Rule | Checked by |
|---|---|
| The seat is the mesh's own, node-scoped, with its verbs and events | A catalogue test on the default seats; registration refuses a claimant that does not serve every verb (design 33's existing check) |
| Creating or removing a mesh-held container is the host's alone | A test of the runtime module's verbs: create or remove of a container carrying the host's label, from any caller but the host's socket, is refused naming the assignment; the same verbs on an unlabelled container succeed |
| No caller but the host creates a container that is root on the machine | A test of `create` from the bus: privileged, a host path, the host's namespaces and the runtime's socket are each refused; the same request on the host's socket is accepted. A broker test: a grant of every tool does not reach a changing verb |
| The host uses the holder and never the command line | A host test with a fake holder on the local socket: every container operation goes to it, and with the holder absent the apply creates nothing and reports the seat; after step 5, the host carries no command-line runtime code (checked by build: the package is gone) |
| A container needs the seat held | A resolution test refusing a containerised assignment on a machine with the seat unheld, naming the seat |
| Socket mounts are granted by the seat | A catalogue test: a module mounting the runtime's socket on a machine whose holder states a different path is refused |
| No other module writes the runtime's file | The existing collision check, once the private network's computed resources are inside it ([issue 190](../04-ISSUES/190-the-runtimes-configuration-is-written-by-modules-that-are-not-the-runtime/00-report.md)) |
| Live | `seats` lists `node-container-runtime` held on every machine; the node listing shows each machine's containers, strays included, from the seat's `list` verb; a container started by hand appears as an event on the bus |
## References
- [ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md), [ADR 0129](0129-a-seat-carries-the-protocol-of-its-role.md), [ADR 0132](0132-a-seat-carries-the-tools-its-holder-must-serve.md), [ADR 0159](0159-a-tool-call-names-the-machine-and-a-holder-serves-its-seats-verbs.md), [ADR 0160](0160-the-mesh-issues-an-assignments-subjects-and-a-runtime-serves-what-it-is-issued.md), [ADR 0161](0161-what-deserves-a-seat.md)
- [ADR 0150](0150-a-modules-own-code-runs-as-supervised-processes-under-one-account.md), [ADR 0142](0142-the-mesh-delivers-its-own-components-as-binaries.md), [ADR 0078](0078-the-store-and-broker-are-modules.md), [ADR 0005](0005-the-node-host.md)
- [ADR 0164](0164-a-setting-is-declared-with-its-default-its-meaning-and-what-changing-it-costs.md), [ADR 0165](0165-container-runtime-is-what-a-machine-can-run-and-a-running-runtime-is-its-holders-health.md), [issue 190](../04-ISSUES/190-the-runtimes-configuration-is-written-by-modules-that-are-not-the-runtime/00-report.md)
- [Design 26 — the seats](../03-DESIGN/01-to-be/26-the-seats.md), [design 33 — the tools the mesh answers](../03-DESIGN/01-to-be/33-the-tools-the-mesh-answers.md)
- mesh-host `internal/apply/apply.go` (the runtime lookup and the command line it drives)
-3
View File
@@ -267,9 +267,6 @@ python3 00-META/checks/index.py fail if stale
- **0150** — [A module's own code runs as supervised processes under the module's one account](0150-a-modules-own-code-runs-as-supervised-processes-under-one-account.md)
- **0152** — [The operator's surface is a module the mesh assigns: the console](0152-the-operators-surface-is-a-module-the-console.md)
- **0155** — [A definition names no installation: how that is checked, and the three ways a value that did gets out](0155-a-definition-names-no-installation-and-how-that-is-checked.md)
- **0164** — [A setting is declared with its default, its meaning and what changing it costs](0164-a-setting-is-declared-with-its-default-its-meaning-and-what-changing-it-costs.md) *(proposed)*
- **0165** — [`container-runtime` is what a machine can run; that a runtime is running is its holder's health](0165-container-runtime-is-what-a-machine-can-run-and-a-running-runtime-is-its-holders-health.md) *(proposed)*
- **0166** — [The container runtime is a node seat, and the host creates containers through its holder](0166-the-container-runtime-is-a-node-seat-and-the-host-creates-containers-through-its-holder.md) *(proposed)*
### How it is built
+10 -1
View File
@@ -7,7 +7,7 @@ code:
- mesh-controller internal/identity/authority.go
- mesh-host internal/identity/serving.go
- mesh-host internal/apply (the service that reflects a rule set)
updated: 2026-09-30
updated: 2026-10-02
decisions:
- 02-DECISIONS/0148-the-meshs-names-are-resolved-not-copied-into-containers.md
- 02-DECISIONS/0151-a-routes-internal-name-is-composed-under-the-node-that-serves-it.md
@@ -842,6 +842,15 @@ One value, three readers:
| `public` | the machine port, to anywhere | the public name | the public authority |
| `both` | the machine port, to anywhere | both names | each name's own authority |
*2026-10-02.* **The proxy serves an internal name to the private network only**
([ADR 0138](../../02-DECISIONS/0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md),
its insight of this date). It answers public and internal names on the same listeners, so the name a
request carries is the request's own claim, not where the request came from. An internal name is
served to the mesh's range, to the machine itself and to its own container networks; to anyone else
it is answered as a name never routed, in the handshake as well as the request. Without this, an
endpoint with reach `internal` would be public under a name that is easy to guess
([issue 191](../../04-ISSUES/191-a-route-with-only-an-internal-name-is-dropped/00-report.md)).
**An endpoint that is not routed is reached and never named.** No route contribution means no name is
composed and no certificate requested, while the filter still acts on it. That is the case the model
could not express at all, and it is the ordinary case for anything that is not HTTP.
@@ -1,78 +0,0 @@
---
status: located
opened: 2026-10-01
located-in: [mesh-catalog modules/dnsmasq, mesh-controller internal/overlay/generator.go, mesh-controller internal/catalogue/resolve.go (checkResources)]
fixed-by:
amended-design:
---
# 190 — The container runtime's configuration is written by modules that are not the runtime's
## What was observed
The runtime's configuration file and its service are declared by two parties, neither of which is
the runtime:
- **The resolver module** writes the runtime's `dns` key (the machine's private address) and
`live-restore` into the runtime's file, written into rather than over
([ADR 0102](../../02-DECISIONS/0102-the-mesh-writes-into-a-shared-file-never-over-it.md)). It also
declares the runtime's service, reloaded when that file changes. The `dns` key has been written
since the resolver module was converted from its predecessor on 2026-09-23; `live-restore` and the
service were added on 2026-09-30 while fixing
[issue 110](../110-a-container-on-the-runtimes-own-network-cannot-reach-the-resolver/00-report.md),
where containers silently resolved through a public resolver.
- **The private network** writes the runtime's `insecure-registries` into the same file, and declares
the same service reloaded on it, as [ADR 0082](../../02-DECISIONS/0082-the-registry-is-reached-by-name-and-trusted-by-the-overlay.md)
and ADR 0102 decided. The controller generates both resources per machine.
On the three machines that run the resolver module, both declare one path and one unit. Nothing refuses
it. The collision check compares the resources of catalogue modules. The private network is computed,
so its resources are produced when a machine's declaration is composed, and the check never sees them.
The machine without the resolver module shows the other half. Its runtime still has the predecessor's
resolver and `live-restore` off, because the only module that sets them is a DNS server. A machine
gets a correct container runtime only as a side effect of being given a resolver.
## Why this is here
The operator ruled it a defect, not a design: **a module does not write another software's
configuration.** The need behind each write is real. Containers must resolve the mesh's names
([ADR 0148](../../02-DECISIONS/0148-the-meshs-names-are-resolved-not-copied-into-containers.md) step 2).
A daemon restart must not stop every container. Every machine on the network must trust the mesh's
registry. But each of these is a fact the runtime must be *given*, and the module that gives it is the
runtime's own. With three writers, nobody can say what the file should contain. Two of the facts are
reloaded when one of them needs a restart (issue 110's first fault). And the moment a module for the
runtime exists, it is refused on every machine with the resolver, or, through the private network's
path, accepted without anyone noticing a collision.
## What resolves it
[ADR 0166](../../02-DECISIONS/0166-the-container-runtime-is-a-node-seat-and-the-host-creates-containers-through-its-holder.md)
gives the runtime a module that holds its seat and owns its file and service.
[ADR 0164](../../02-DECISIONS/0164-a-setting-is-declared-with-its-default-its-meaning-and-what-changing-it-costs.md)
gives that module declared settings with defaults. The fix, once both are accepted:
1. The resolver module drops its runtime file and runtime service. It knows nothing of the runtime.
2. The private network stops generating either resource. ADR 0082's decision stands — being on the
network is what grants the trust, and no module author is involved — and only *who writes it*
moves. The mesh gives the registry to the runtime module as a value. ADR 0082 and ADR 0102 each
get a dated note saying where their mechanism now lives.
3. The runtime module writes `dns`, `live-restore` and `insecure-registries`, each a declared
setting with its cost: `dns` costs a restart, which `live-restore` makes harmless.
4. Steps 1–3 land in one push. A runtime module declaring the file beside a resolver module still
declaring it is refused.
5. The collision check sees a computed module's resources as well, so a second writer cannot come
back through generated code.
## Open questions
- **How the resolver's address reaches the runtime.** Either the resolver seat (`node-dns-resolver`)
delivers an address its holder serves, or the runtime module reads a machine fact and the seat
being held is only a precondition. The first tracks a resolver moving off the private address. The
second needs nothing new.
- **What `dns` defaults to on a machine with no resolver seat held.** Nothing, leaving the runtime's
own behaviour, is the honest default. A public resolver hides exactly the failure issue 110 took a
day to find.
- **The adopted machine's predecessor values.** The runtime module adopting a file with a
hand-written `dns` and `live-restore: false` replaces both. That is intended, and is the one
restart the operator must make on that machine.
@@ -0,0 +1,61 @@
---
status: located
opened: 2026-10-01
located-in: [mesh-controller examples/route-proxy/main.go (routesFrom requires a route's public `name` and treats `internal-name` only as an alias of it; the handler serves every routed name to any source), mesh-catalog modules/route-proxy/module.json (the proxy is not told the private network's range)]
fixed-by:
amended-design: [03-DESIGN/01-to-be/08-connectivity.md]
---
# 191 — A route with only an internal name is dropped as naming nothing
## What was observed
A module whose endpoint reaches only the private network could not be reached by its internal name.
The module ran and answered on its own port. Its route's internal name resolved to the serving node.
The request failed during the TLS handshake:
```
http: TLS handshake error from …: no public route for "unifi.home-server.internal" in this mesh,
so no certificate is asked for
```
The proxy's own log said why, every time it re-read its routes:
```
unifi on home-server asked for a route and named nothing; skipped
```
The route it skipped was not empty. The mesh had given it an endpoint, a port, a scheme and an internal
name, and no public name:
| route | `name` | `internal-name` | served |
|---|---|---|---|
| home-assistant | a public name | `home-assistant.home-server.internal` | under both |
| unifi | — | `unifi.home-server.internal` | under neither |
Three other modules on the same node were skipped with the same line on the same pass.
## Why it matters
**Reach is decided in one place, and the proxy reads the old shape of the decision.**
[ADR 0138](../../02-DECISIONS/0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md)
made an endpoint's reach decide which names exist. The controller composes the public name, the
internal name, or both, and composes no name that nobody asked for
([issue 140](../140-an-endpoints-reach-is-not-declared/01-resolution.md)). An endpoint that reaches
only the private network is the ordinary case for anything that should not face the internet. It is
exactly the case the proxy drops.
**The failure is quiet and points the wrong way.** Nothing marks the module unhealthy. The handshake
error says *no public route*, which reads as a certificate fault on the reader's side. The line that
gives the real cause is one of four identical lines repeated every few seconds in a log nobody reads
until they already suspect the proxy.
**The opposite move is not a workaround.** Giving the endpoint public reach makes the proxy serve it.
It also publishes an administration interface to the internet to get a name on the private network.
## Open questions
- Should the proxy refuse a route it cannot serve in a way the controller or an operator sees, not
only in its own log? The same silent skip covers a route with no usable port or an unknown scheme.
- What checks that what the controller composes and what the proxy serves stay the same shape? ADR
0138 changed one side and nothing failed on the other.
@@ -0,0 +1,65 @@
# Diagnosis
*2026-10-01.*
**Ruled out first: the module itself.** Its container was up and had not restarted. The controller's
status endpoint answered on its own port with `"up": true`. The tool wrapper beside it was serving
all its tools.
**Ruled out: name resolution.** The internal name resolved to the serving node's private-network
address, which is where the proxy listens. Plain HTTP to the name reached the proxy and got a 404.
HTTPS failed in the handshake, and the proxy logged that it had no route for the name.
**The route as the proxy received it.** The mesh-written route file held a complete contribution
for the module: endpoint `web`, port, scheme `https`, `insecure`, a label, and `internal-name`. It had
no `name`. That is what the controller composes for an endpoint whose reach stops at the private
network (ADR 0138, `composeName`). The contribution was correct.
**Located: `routesFrom` in the proxy.** It reads `name` first and skips the contribution if `name`
is empty. It reads `internal-name` only at the end, as a second host for a rule that already has a
public one. So the proxy can serve an internal name only next to a public one. That matched the
mesh before ADR 0138, when both names were always composed. It has been wrong since then.
The other half of the proxy already handles the case. Certificates for a host are split by whether it
is in the public set: hosts outside it go to the internal authority, and only hosts inside it are
eligible for ACME. A host that is only ever an internal name falls on the correct side of both checks
without change. For certificates, only reading the route was wrong; who may reach the route is the next section.
**The fix.** `routesFrom` takes a route that names either host, serves each name it carries, and
marks only the public one as public. It still skips a route that names neither, with the same log line.
A test proves an internal-only route is served, certified by the internal authority, and refused by
the public one. That test fails against the code before the change.
## The first fix would have made the name public — 2026-10-02, from review
Serving the dropped route was not enough. The proxy picks a route from the name a request carries
and never from where the request came from, and it answers public and internal names on the same
listeners. Its public names resolve to an address the internet reaches. So once the internal-only
route was served, any request from the internet carrying `unifi.home-server.internal` — a name of a
fixed, guessable shape — would have reached an administration interface that reach `internal` was
chosen to keep private. Before the fix the route was unreachable from everywhere. After it, it would
have been reachable from everywhere. Two more leaks came with it: the proxy's answer for an unrouted
name listed every name it serves, internal ones included, and the handshake handed a certificate
naming the internal host to any client.
Nothing showed this while every routed endpoint also had a public name: its internal name exposed
nothing the public one did not. It is a gap in the decision's wording, not only in the proxy — ADR
0138 says the proxy *serves* the internal name without saying to whom — so it is recorded there as a
progressive insight and in the to-be connectivity design.
**Where "inside" is decided.** The mesh's guard recognises the private network by the interface a
packet arrives on, never by source address, because a source can be claimed. The proxy cannot see the
interface, so it reads the source: the mesh's range, loopback, and the ranges of the machine's own
container bridges, which are the same interfaces the guard names. A claimed source does not carry
here, as a connection needs its replies, and replies to those addresses leave by the tunnel or a
local bridge. The range reaches the proxy from the catalog as the machine's `mesh-range`, the way the
intrusion filter already receives it. With none given, the proxy serves internal names to the machine
alone: refused, not opened.
**What changed with it.** The internal name of a route that also has a public one is now served to
the private network only, like any other internal name. Outsiders have the public name, so nothing
they could reach is lost.
**Order of release.** The catalog change comes first. A proxy built from the change but started
without the range would serve internal names to its own machine alone, and every other member of the
mesh would lose them until the range arrived.