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A config dump with nothing pushed into it: three facts that all invert once a control plane exists

Claim — every resource in your static Envoy's /config_dump is under a static_* key, no entry carries a version_info, and one of the four objects has no top-level section of its own at all. All three are consequences of there being no control plane, and all three invert in the sidecar's dump — which is the only reason that dump is legible on first contact.

Rests on — the config you typed, still running or restarted from the same file.

Topology — none. forge only.

Setup — if you tore Envoy down, bring the same config back:

ssh zain@10.10.10.125
(cd /tmp/up1 && python3 -m http.server 8081 >/dev/null 2>&1 &)
(cd /tmp/up2 && python3 -m http.server 8082 >/dev/null 2>&1 &)
docker run -d --name academy-envoy --network host \
  -v ~/envoy-academy/envoy.yaml:/etc/envoy.yaml:ro \
  --entrypoint /usr/local/bin/envoy \
  docker.io/istio/proxyv2:<ISTIO_VERSION> -c /etc/envoy.yaml -l info

Do — take the dump once, keep it, and read it offline. It is 30 KB now and it is 400 KB in module 9.3; the habit of saving it is worth forming on the small one:

curl -s localhost:9901/config_dump > ~/envoy-academy/dump-static.json
wc -c ~/envoy-academy/dump-static.json
jq -r '.configs[]."@type"' ~/envoy-academy/dump-static.json

Observe — three questions, each answered by one filter over that file:

jq -r '.configs[] | select(."@type"|test("ListenersConfigDump")) | keys[]' ~/envoy-academy/dump-static.json
jq -r '.configs[] | select(."@type"|test("ClustersConfigDump")) | keys[]' ~/envoy-academy/dump-static.json
jq '[.. | .version_info? // empty] | length' ~/envoy-academy/dump-static.json
jq -r '.configs[] | select(."@type"|test("RoutesConfigDump"))' ~/envoy-academy/dump-static.json

Then find your route config by name, wherever it actually lives:

grep -c academy_routes ~/envoy-academy/dump-static.json
jq -r 'paths(scalars) as $p | select(getpath($p)=="academy_routes") | $p|join(".")' ~/envoy-academy/dump-static.json

Expect — static_listeners and static_clusters present, dynamic_listeners and dynamic_active_clusters absent or empty, and zero version_info fields in the entire document. A version is a control plane's serial number for a push; nothing pushed, so nothing is versioned.

Expect the route config to be nested inside the listener, not listed beside it — its path runs through the HTTP connection manager's typed_config, because you inlined it. That is not a quirk of your file: an inline route config is the RDS-less case, and the reason RDS exists as a separate resource type is precisely to lift that nested object out and version it on its own. You have just built the before picture for the four-type walk without meaning to.

Expect BootstrapConfigDump to be the first entry and to contain your whole file. In a sidecar it contains something you did not write, and the dynamic dump is where you find out who did.

Write down — the three answers (static_* keys, the version_info count of zero, the JSON path where academy_routes was found) in journal/p9-static-dump.md, and keep dump-static.json itself. It is the control in an experiment whose treatment arrives in module 9.3.

Teardown

docker rm -f academy-envoy
pkill -f 'http.server 808'

Keep ~/envoy-academy/, including dump-static.json — the failure-ownership exercise restarts the same proxy and module 9.3 compares against this file. No topology to release; none exists yet.