decolua/9router · error · Error

Failed to toggle DNS

Error message

Failed to toggle DNS

What it means

MitmToolCard's doDnsAction throws this when the PATCH to /api/cli-tools/antigravity-mitm fails and the response has no explicit error message. The endpoint toggles a system DNS override for the MITM tool, which typically requires elevation (sudo password); the fallback message hides whether it was auth, wrong sudo password, or an OS-level failure.

Source

Thrown at src/app/(dashboard)/dashboard/cli-tools/components/MitmToolCard.js:109

      doDnsAction(action, "");
    } else {
      setPendingDnsAction(action);
      setShowPasswordModal(true);
      setModalError(null);
    }
  };

  const doDnsAction = async (action, password) => {
    setLoading(true);
    setWarning(null);
    try {
      const res = await fetch("/api/cli-tools/antigravity-mitm", {
        method: "PATCH",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ tool: tool.id, action, sudoPassword: password }),
      });
      const data = await res.json();
      if (!res.ok) throw new Error(data.error || "Failed to toggle DNS");

      if (action === "enable") {
        setWarning(`Restart ${tool.name} to apply changes`);
      }

      setShowPasswordModal(false);
      setSudoPassword("");
      onDnsChange?.(data);
    } catch { /* ignore */ } finally {
      setLoading(false);
      setPendingDnsAction(null);
    }
  };

  const handleConfirmPassword = () => {
    if (!sudoPassword.trim()) {
      setModalError("Sudo password is required");
      return;

View on GitHub (pinned to 90b52e06ff)

Solutions

1. Inspect the response body/status from the PATCH call for the server's real error text
2. Re-enter the sudo password carefully (wrong passwords commonly surface as this generic error)
3. Check whether the backend can modify the system resolver config (permissions, systemd-resolved conflicts) via server logs
4. Retry the toggle after fixing OS-level conflicts (e.g. disable systemd-resolved DNS stub handling)

Example fix

// before
if (!res.ok) throw new Error(data.error || "Failed to toggle DNS");
// after
if (!res.ok) throw new Error(data.error || `Failed to toggle DNS (HTTP ${res.status})`);

// before toggling
if (!password) { setShowPasswordModal(true); return; }

try {
  const res = await fetch("/api/cli-tools/antigravity-mitm", { method: "PATCH", body: JSON.stringify({ tool, action, sudoPassword: password }) });
  const data = await res.json().catch(() => ({}));
  if (!res.ok) throw new Error(data.error || `Failed to toggle DNS (HTTP ${res.status})`);
} catch (e) {
  setWarning(e.message);
}

When it happens

Trigger: PATCH /api/cli-tools/antigravity-mitm with {tool, action:'enable'|'disable', sudoPassword} returns non-2xx: wrong/empty sudo password, server cannot modify resolv.conf or the OS resolver, backend helper missing, or unauthenticated session.

Common situations: User submits the password modal with an incorrect sudo password; on systems where /etc/resolv.conf is managed by systemd-resolved or NetworkManager and cannot be written; action enable/disable sent with a tool id the backend doesn't recognize.

Understand the failure class

Background: 'Something went wrong' / 'Request failed (500)' / 'HTTP error! status: 404' — what failed HTTP requests actually mean and how to find the real cause — this error's family across 28 libraries.

Related errors

• Failed to save mappings
• extras status failed
• Failed to start proxy
• Install failed
• Failed to fetch image: ${res.status}

AI-assisted analysis of decolua/9router@90b52e06ff (2026-08-30). Data as JSON: /api/errors/6b662d02d33ad7d2. Report an issue: GitHub.