The signing keys Ankusa.Admin.Auth.JWT verifies against, for every control plane of an instance that runs mode: :jwt. Started with the instance (only when some listener needs it).

Each listener's keys are the jwt.keys it was configured with, loaded at start, plus the keys of its jwt.jwks_url:

• fetched right after start, without delaying it, and again every jwt.refresh_ms;
• refetched early, at most once per jwt.min_refresh_ms, when a token names a kid that is not in the set (the provider rotated its keys);
• kept, not dropped, when a refetch fails: a provider outage must not lock operators out of a running node. The failure is a warning and the next attempt comes sooner. Until the first fetch succeeds there are no keys and every token is refused.

Only public RSA, EC and OKP keys are kept; a JWKS entry for encryption (use: "enc"), a shared key or a private key is skipped. The set is read from an ETS table by the request, never through this process.