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jschoubben 0a37d751e2 Graduate research 003; file the rescue that does not exist

A sweep of the nine active research efforts. 003 was answered five days ago and
nobody closed it -- the decision it asked for was taken without citing it, which
is how an effort stays `active` after being resolved.

Its recommendation is what the mesh adopted, and the match is exact rather than
approximate. "Run the daemons as containers, making Docker the supervisor for
everything" is ADR 0057. Its warning that a mesh-native supervisor inherits
fate-sharing "unless it sits outside the mesh's own process tree" is where ADR
0061 put the launcher. And its insistence that it cannot be all-or-nothing is
why the host itself is the one thing an init starts.

Its incidental finding does not graduate with it, so it is now issue 008: the
automatic node rescue the documentation describes does not exist. No unit
declares OnFailure=, nothing calls the rescue script on a timer.

That is worse than having no rescue. A rescue nobody wrote is a gap somebody
can see; a documented one that is absent is a gap nobody looks for, and the
documentation is read exactly when a node has failed and somebody is deciding
whether to intervene.

The issue names two honest resolutions -- implement it, or delete the
documentation and say a failed node needs a person -- and says the choice is
scheduling rather than technical, since the new host's recovery is built and
tested. It also says what would make the finding certain: it came from reading
the repository, and confirming it on a running node is the difference between
"no unit declares this" and "no unit in the source declares this".

2026-08-28 01:39:10 +02:00

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status, initiated, touches, became

status

initiated

touches

became

graduated

2026-08-22

03-DESIGN/00-as-is/05-runtime-and-installation.md

02-DECISIONS/0057-the-host-is-a-root-service-installed-as-a-package.md

02-DECISIONS/0061-the-host-asks-an-init-for-start-and-restart.md

03-DESIGN/01-to-be/05-the-node-host.md

003 — Who supervises a service

No longer blocks Phase 0 (see below).

Initiated by: jochen, 2026-08-22, in response to 002-local-mesh open question 1
Areas touched: every module shipping a systemd/ directory (14), the hal-module@ template, hal/sdk feature handlers, dev_up, log_tail / systemd_journal, the bootstrap scripts.

The question

002 asked how a containerised node runs a module service, given that a module service is defined today as a systemd unit running docker compose against /services/. The response was the better question:

If it's possible to run systemd inside a container, that's the way to go I think. However, what would the cost be to step away from systemd to run our services and set it up in a different way? More hal mesh approach.

This effort answers the cost half. It does not choose.

Summary of findings

The question splits in two, and the halves have opposite answers. Supervising docker compose stacks through systemd is largely redundant — 44 of 44 module compose files already declare a restart policy, so Docker is already the supervisor. Supervising HAL's 9 long-running Node daemons is not redundant: Restart=always is currently the only thing between a crash and a dead node.
The hard part is fate-sharing, not systemd. meshware already cannot restart itself and carries a documented workaround for it. Any mesh-native supervisor inherits that problem recursively unless it sits outside the mesh's own process tree — at which point it is an OS-level supervisor again, just reinvented.
There is a third option neither of us named, and it is the one that also solves Phase 0: run HAL's own daemons as containers, making Docker the supervisor for everything. Local and production then have the same shape rather than a translation layer between them.
It cannot be all-or-nothing, and ADR 0015 already says why: a human agent acts through a shell and a desktop. Those parts are on the host by definition.
One incidental finding: the automatic node rescue that documentation describes does not exist. No unit declares OnFailure=, and nothing calls hal-rescue.sh on a timer.

Detail and costs in analysis.md.

What it became

Closed 2026-08-28. The decision this effort asked for was taken — and taken without citing it, which is why the effort sat active for five days after being answered. Recorded here because finding that is the point of a sweep.

The third option is what the mesh adopted. Docker is the supervisor for everything is ADR 0057: the host is a plain process on the machine and everything above tier 0 is a container. The substrate bootstrap declares no service at all — it is package, container, action, container — so the 44-of-44 restart policies this effort counted are the supervision, exactly as it argued.

Fate-sharing was the hard part, and it is solved the way this effort predicted. It said any mesh-native supervisor inherits the problem unless it sits outside the mesh's own process tree. ADR 0061 puts the launcher there: it supervises the host as a child and shares no code with it, so a host that cannot start is still recovered.

It is not all-or-nothing, as this effort insisted. A human agent acts through a shell and a desktop, and those are on the host. So is the host itself — the one thing an init starts.

What is not closed

The automatic node rescue the documentation describes does not exist. No unit declares OnFailure=, and nothing calls the rescue script on a timer. That is a documented behaviour which never happens, and it outlives this effort — filed as 04-ISSUES/008 rather than closed with it.

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