The scraper shipped with no targets, so nothing exercised it. This is its
first user, and the one with the least new surface: victoriametrics
publishes prometheus metrics on the listener it already serves queries on,
so there is no exporter, no extra port and no new reach — the collector's
otlphttp exporter already writes to that same loopback address.
Declared from this module rather than the collector's, per the option's own
rule: an entry exists only where the service that named it runs.
A swarm service container shares the host netns and force-disables
resolvconf, so it inherits the /etc/resolv.conf nixos-containers copies in
at start (cp --remove-destination, host-side preStart, once per start) and
nothing ever refreshes it. That makes the container's resolver a snapshot of
the host's file at its boot instant.
When that snapshot is wrong the container can never recover, and the symptom
appears arbitrarily far from the cause: swarm-nats-auth cannot resolve
authelia's name, so it denies every auth-callout request and the queue
refuses every client with an authorization violation.
Give each of the four swarm containers a oneshot that writes the resolver
file itself, from the bridge IP, ordered before that container's first DNS
consumer. The shape is the one every agent container already uses.
networking.nameservers cannot do this: resolvconf is its only consumer and
these containers disable it, so setting it renders no file while still
evaluating cleanly. A static environment.etc entry cannot either -- it would
have to survive etc activation landing on the regular file the host already
copied there, which no eval can show.
A local time-series database rather than only an external sink, so the
swarm dashboard stays readable when the outside world is not: a view of
the system must not depend on the system it views being healthy.
listenAddress is pinned to loopback. Upstream defaults it to every
interface, and the OTLP ingest path this exists to receive on is
unauthenticated — the gateway is the only intended client and it is on
this host, so a wider bind would publish a write endpoint to whatever
the host is reachable on.
retentionPeriod defaults high rather than being required, because the
two failure directions are not symmetric: too long fills a disk, which
is visible and recoverable by lowering it, while too short destroys
history silently and permanently. The operator lowers it once they have
measured how fast this swarm accumulates.
OTLP needs no flag. Measured against the pinned 1.146.0 rather than
inferred from the module's option list, which has no OTLP switch and so
reads as though the feature were missing: the running server answers
POST /opentelemetry/api/v1/push with 200, where a nonexistent path
answers 400.
