hyperhive/nix/host-modules/swarm-victorialogs.nix
atlas 4336436457 swarm-otel: collect only the units the swarm's services declare
The journald receiver was configured with a directory and no filter, so
the swarm's log store received every unit on the host that runs the
collector. On a hive whose services live on a workstation that includes
the operator's desktop session, in a store every swarm operator can read.

The receiver has no system-only switch and its `matches` field is an
allowlist too, so what the swarm collects has to be stated rather than
excluded. Each service module names its own units: a service that is not
running contributes nothing, and one added later arrives declared.

An empty list is fail-open — the receiver renders no filter at all and
reads everything — so it is asserted against.
2026-08-24 22:05:45 +02:00

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# The swarm's log store: one VictoriaLogs for the whole swarm, in a
# `swarm-victorialogs` nixos-container beside the metrics store it mirrors.
#
# Why a store at all rather than reading journals directly: an agent can
# verify that a unit was *launched* and never that it is *working*. The
# container journals are not reachable from an agent, so a diagnosis stops at
# the first component that is broken — which is precisely the component whose
# own instrument is least likely to be legible. Collecting logs centrally
# makes the question answerable without host access.
#
# It is the collector that feeds this, not the services directly: one ingest
# point per swarm, same shape as the metrics path.
#
# Gateway vhost is authenticated, unlike the metrics store's: an operator
# reaches this at `https://${cfg.domain}/` gated by the same `auth_request`
# check against authelia that swarm-ui's own vhost uses (`swarmAuthRequest`
# below, same shape as `swarm-ui.nix`'s) — see that file's copy for the full
# rationale (forceSSL is load-bearing there too: authelia answers a plain-http
# auth subrequest with 400, which `auth_request` cannot interpret as anything
# but a broken check). The store's own listener stays loopback-only and
# unauthenticated exactly as before — the collector still writes to it
# directly, never through this vhost — so this adds a new authenticated front
# door without touching the existing write path at all.
{
pkgs,
lib,
config,
...
}:
let
cfg = config.services.hyperhive.swarm.victorialogs;
networkCfg = config.services.hyperhive.network;
hyperhiveCfg = config.services.hyperhive;
gatewayCfg = hyperhiveCfg.gateway;
autheliaCfg = hyperhiveCfg.swarm.authelia;
swarmDomain = hyperhiveCfg.swarm.domain;
# Total on a null swarm domain for the same reason every sibling module is:
# the required-domain assertion in hive-network.nix should be what an
# operator sees, not a coercion error from here.
domainBase = if swarmDomain == null then "invalid" else swarmDomain;
# Copy of `swarm-ui.nix`'s own `swarmAuthRequest` — not shared code because
# this vhost needs exactly the two locations that reference it (`/` and the
# internal auth-request target below) and pulling in swarm-ui.nix for one
# string would couple this module to swarm-ui existing at all, which it
# need not. Same three lines, same reasoning as that file's own comment.
swarmAuthRequest = ''
auth_request /__hive_authelia;
auth_request_set $target_url $scheme://$http_host$request_uri;
error_page 401 =302 https://${autheliaCfg.domain}/?rd=$target_url;
'';
in
{
options.services.hyperhive.swarm.victorialogs = {
enable = lib.mkOption {
type = lib.types.bool;
default = false;
description = ''
Run the swarm's log store on this host. Off by default and not
derived from {option}`services.hyperhive.enable`: a swarm has one
log store, so enabling it is a decision about swarm topology
rather than about whether hyperhive is installed.
'';
};
package = lib.mkOption {
type = lib.types.package;
default = pkgs.victorialogs;
defaultText = lib.literalExpression "pkgs.victorialogs";
description = "VictoriaLogs package to run.";
};
machine = lib.mkOption {
type = lib.types.str;
readOnly = true;
default = "swarm-victorialogs";
description = ''
Container name. Read-only: the name appears in host paths and in
`machinectl`, so it is a fact other modules may read rather than a
knob.
'';
};
domain = lib.mkOption {
type = lib.types.str;
default = "logs.${domainBase}";
defaultText = lib.literalExpression ''"logs.''${services.hyperhive.swarm.domain}"'';
description = ''
Name the gateway serves this on, behind the same authelia
`auth_request` gate as the swarm UI's own vhost. A sibling of the
swarm's other service names, so the swarm-services sub-CA can
issue for it see `hive-tls.nix` for why a service name being a
sibling rather than a child decides which CA may sign it, and
`swarm.nix`'s `serviceDomains'` for where this name has to be
registered for that to actually happen.
'';
};
port = lib.mkOption {
type = lib.types.port;
default = 9428;
description = ''
Loopback port the store listens on. Upstream's default, kept
because there is no reason to move it and a familiar number is
one less thing an operator has to look up.
Every swarm container shares the host's network namespace, so
this is a swarm-wide claim rather than a per-container one two
modules picking the same number collide at runtime with no bind
error and nothing in any log. `state/eval-port-collisions.sh`
checks the class.
'';
};
retentionPeriod = lib.mkOption {
type = lib.types.str;
default = "30d";
example = "90d";
description = ''
How long log data is kept.
Deliberately far shorter than the metrics store's retention: logs
are orders of magnitude larger per unit of time, and their value
decays much faster. A log line answers "what happened during that
incident"; a metric answers "is this worse than last quarter".
'';
};
};
config = lib.mkIf (hyperhiveCfg.enable && cfg.enable) {
# This store publishes its own health as prometheus metrics on the same
# listener it serves queries on, so the swarm's collector scrapes it with
# no exporter and no extra port — same arrangement as the metrics store.
#
# Declared here rather than in the collector's module because that is the
# rule the option carries: an entry exists only where the service that
# named it runs. ⚠️ That constrains the TARGET, not the scraper — a
# deployment that splits this container away from the collector's host
# silently drops the entry, and no assertion can see it, because separate
# hosts are separate evaluations.
services.hyperhive.swarm.otel.scrapeTargets.victorialogs = "127.0.0.1:${toString cfg.port}";
# The gateway name and the quick-link, both inside `cfg.enable` — same
# "only the host that runs the service may claim the name" guard every
# sibling swarm-service module uses (`swarm-grafana.nix`,
# `swarm-victoriametrics.nix`).
services.hyperhive.gateway.localNames = [ cfg.domain ];
# Declared here rather than in the collector, so this store's logs are
# collected because it runs, not because a list elsewhere remembered it.
services.hyperhive.swarm.otel.journaldUnits = [ "victorialogs" ];
services.hyperhive.swarm.controller.links = [
{
label = "Logs";
icon = "📜";
url = "https://${cfg.domain}/";
}
];
# Authenticated front door onto the loopback-only store — see the
# file-top comment for why this is safe to add without touching the
# store's own (still unauthenticated, still loopback) listener at all.
# `removeAttrs`/`forceSSL`: same asymmetry `swarm-ui.nix` documents —
# authelia answers a plain-http auth subrequest with 400, which
# `auth_request` cannot read as anything but a broken check, so this
# vhost needs `forceSSL` rather than the `addSSL` every unauthenticated
# sibling vhost uses.
services.nginx.virtualHosts."${cfg.domain}" =
(builtins.removeAttrs (gatewayCfg.lib.tlsFor cfg.domain) [ "addSSL" ])
// {
forceSSL = true;
listen = gatewayCfg.lib.listen;
extraConfig = gatewayCfg.lib.securityHeaders;
locations = {
"/" = {
proxyPass = "http://127.0.0.1:${toString cfg.port}/";
extraConfig = swarmAuthRequest;
};
# The subrequest itself — same target, same header set, same
# reasoning as `swarm-ui.nix`'s own copy (measured against the
# pinned authelia binary, not copied from an example).
"= /__hive_authelia" = {
proxyPass = "http://127.0.0.1:${toString autheliaCfg.port}/api/authz/auth-request";
extraConfig = ''
internal;
proxy_pass_request_body off;
proxy_set_header Content-Length "";
proxy_set_header X-Original-Method $request_method;
proxy_set_header X-Original-URL $scheme://$http_host$request_uri;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Forwarded-Host $http_host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
'';
};
};
};
containers.${cfg.machine} = {
autoStart = true;
ephemeral = false;
# Shared host netns, like every sibling swarm container: the collector
# and Grafana reach this at 127.0.0.1:<port>.
privateNetwork = false;
config =
{ ... }:
{
imports = [
(import ./swarm-container-resolver.nix {
inherit (networkCfg) bridgeIp;
dnsConsumers = [ "victorialogs.service" ];
})
];
system.stateVersion = "26.05";
# This container shares the host netns, so its own firewall.service
# would rewrite the HOST ruleset at every boot. The host firewall
# owns all filtering.
networking.firewall.enable = false;
# resolvconf stays off because the resolver unit imported above
# owns /etc/resolv.conf. Leaving it on would let host-tracking
# regenerate the file empty, since the host's copy doesn't cross
# the boundary after start.
networking.resolvconf.enable = lib.mkForce false;
services.victorialogs = {
enable = true;
package = cfg.package;
# ⚠️ PINNED TO LOOPBACK for the same reason the metrics store is,
# and it matters more here: upstream's default listens on every
# interface, and this endpoint accepts writes as well as reads
# with no authentication of its own. The bind address is the
# boundary.
listenAddress = "127.0.0.1:${toString cfg.port}";
extraOptions = [ "-retentionPeriod=${cfg.retentionPeriod}" ];
};
};
};
};
# 🔑 OTLP ingest is served at `/insert/opentelemetry/v1/logs`, measured
# against the pinned build rather than read from docs. The path differs
# from the metrics store's `/opentelemetry/api/v1/push`, so an exporter
# configured by analogy with the metrics one is silently wrong.
#
# ⚠️ And the status code cannot tell you which is which: a wrong path, a
# right path with a wrong body, and a nonsense path ALL answer 400. Only
# the server log distinguishes them — the real route complains about the
# encoding ("json encoding isn't supported ... use protobuf"), while
# anything else logs "unsupported path requested". Verified with a
# nonsense-path control, because a probe where every arm returns the same
# code is not evidence.
#
# ⚠️ Like the metrics store's, that endpoint is unauthenticated — which is
# why `listenAddress` above is loopback, why the collector is the only
# writer, and why this module declares no gateway vhost.
}