jschoubben
3bd6f34de3
Both found migrating the first module on ace (searxng), adopted with route-adapter: 147 — assign is not a no-op for a routed module: its route reaches the predecessor's proxy while its container is held, and the name serves a dead backend until take. 148 — every push that moved the mesh's names replaced every container on novox, twice, the control plane's own store included.
65 lines
3.4 KiB
Markdown
65 lines
3.4 KiB
Markdown
---
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status: open
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opened: 2026-09-29
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located-in:
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- mesh-host internal/apply/apply.go (containerSpecReading hashes every `host` entry)
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- mesh-controller internal/catalogue/declaration.go (withMeshNames gives every container the mesh's names)
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fixed-by:
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---
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# 148 — A new name recreates every container in the mesh
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## What was observed
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Migrating one small module on ace (searxng) took four routine controller actions: `node public-domain
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ace zurag.be`, `assign ace searxng` + push, `unassign ace searxng` + push (a rollback, see
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[issue 147](../147-a-route-is-contributed-before-its-module-is-taken/00-report.md)), and assign + take
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+ push again. Each push to ace also pushed novox ("this push left g14, novox, shanks behind … sending it
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too"). novox's host then **replaced every container it runs, twice**:
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```
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22:46 … updated postgres.server (mesh-store): replaced; a container's configuration is fixed when it is created
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22:46 … updated distribution.store (mesh-registry): replaced; …
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22:46 … updated route-proxy.server (route-proxy): recreated …
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22:51 … updated postgres.server (mesh-store): replaced; …
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22:52 … updated gitea.server (gitea): replaced; …
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22:52–22:55 mesh-vault, builder, all of mailu, keycloak, minio, mongodb, invoicing, photos, umami, …
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```
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Replacements per minute on novox, 22:46–22:55: 12, 8, 13, 5, 6, 8, 8, 8, 8, 4. The control plane was
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unreachable twice while its own store came back through crash recovery
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(`FATAL: the database system is starting up`), and dependants (umami) crash-looped until it did. None
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of the replaced containers belonged to the module being migrated, or to ace.
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## Why (confirmed part)
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Every container the mesh runs is given the mesh's names as `--add-host` entries
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(`withMeshNames`), and the host puts every entry into the container's spec digest — deliberately,
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since [issue 135](../135-a-containers-mesh-names-are-not-compared/00-report.md): a container left alone when the roster moved kept a five-day-old
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address and restarted 2286 times. A running container cannot have its hosts changed, so a changed
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digest means a replace.
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The consequence is that **the roster is part of every container everywhere**: anything that adds,
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removes or moves one name — a node's public domain, a routed name, an unassign — replaces every
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container on every machine that carries the list. On the hub that includes the control plane's store,
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the registry, the edge and mail.
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## Not yet established
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Which name moved in each pass. gitea's hosts after the fact list the `.internal` names and novox's
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internally routed `*.novox.be` names, and **not** `searxng.zurag.be` — so it is not simply "a routed
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name was added". Two passes suggest the set changed at assign and changed back at unassign; the
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declarations before and after would say, and nothing on the machine records the previous one.
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## Why it matters now
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The node-by-node migration adds names one module at a time. On ace alone that is ~25 web modules; if
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each assignment moves the roster, each is a full restart of every hub service, and a rollback is
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another. The migration is paused on this.
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## What would be right (for diagnosis)
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Keep 135's guarantee (no container runs with a stale address) without making the roster part of every
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container's identity — e.g. resolve mesh names through a resolver the container asks at lookup time
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rather than baked entries, or scope each container's entries to the names it actually binds.
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