2026-09-05 10:27:11 +00:00
1 changed files with 25 additions and 2 deletions
@@ -278,13 +278,36 @@ somebody starts by hand is not the mesh's to configure, and reaching into every
 machine — declared or not — is what a nameserver in `resolv.conf` would be for.

 **That is now the second reason to want a resolver**, and it is a different one from the trigger
-above. Both remain unmet needs rather than plans:
+above:

 | | |
 |---|---|
-| names that are not one-per-node | `postgres.internal` meaning *wherever the database is* |
+| names that are not one-per-node | a service named under a machine — `postgres.novox.internal` |
 | containers the mesh did not declare | anything a person or another tool starts on a node |

+### Which resolver is not a question the mesh answers
+
+*Written 2026-08-31, after treating it as open when it had been decided two days earlier.*
+
+**A resolver takes over `/etc/resolv.conf`, which is a singular resource, so it is a claim** —
+[ADR 0009](../../02-DECISIONS/0009-modules-and-the-graph.md) lists it in the table beside the seat
+and pid 1. Choosing between resolved, dnsmasq and unbound is **assigning a module**, per machine,
+and two of them cannot both be assigned there:
+
+> `resolved-config and dnsmasq both claim "/etc/resolv.conf", and only one thing may hold it per node`
+
+So there is nothing global to settle and nothing for the mesh to guess. One machine can use what
+systemd already owns and another can run dnsmasq, and neither has to know about the other.
+
+**What the mesh contributes is the part only it can know**: which machines exist and where. That
+is `mesh-resolver`, which writes one file and holds no claim, because writing a file takes nothing
+over. A daemon module requires that data and claims the resolver — so swapping the daemon changes
+that module and nothing else.
+
+**This was recorded on 2026-08-29 and reopened as an unanswered question on the 31st.** Which is
+the argument for the table in ADR 0009 being a table: the pattern is only obvious once seen, and
+the cost of not seeing it is inventing a mechanism that already exists.
+
 ## 3 — Exposure

 Settled by [ADR 0007](../../02-DECISIONS/0007-connectivity.md); summarised here because