owasp-amass/amass · error

failed to obtain the BGPTools IP address

Error message

failed to obtain the BGPTools IP address

What it means

The bgptools whois plugin's Start method resolves bgp.tools via DNS (support.PerformQuery for an A record) to learn the WHOIS server's IP address. If that lookup fails, Start wraps the underlying error with fmt.Errorf("failed to obtain the BGPTools IP address: %v", err) and aborts plugin startup. Without the server IP the plugin cannot open WHOIS connections.

Source

Thrown at engine/plugins/whois/bgptools/plugin.go:66

		},
	}
}

func (bt *bgpTools) Name() string {
	return bt.name
}

func (bt *bgpTools) Start(r et.Registry) error {
	bt.log = r.Log().WithGroup("plugin").With("name", bt.name)

	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
	defer cancel()

	rr, err := support.PerformQuery(ctx, "bgp.tools", dns.TypeA)
	if err != nil {
		return fmt.Errorf("failed to obtain the BGPTools IP address: %v", err)
	} else if len(rr) == 0 {
		return errors.New("failed to obtain the BGPTools IP address")
	}

	for _, record := range rr {
		if record.Header().Rrtype == dns.TypeA {
			bt.addr = strings.TrimSpace((record.(*dns.A)).A.String())
			break
		}
	}
	if bt.addr == "" {
		return errors.New("failed to obtain the BGPTools IP address")
	}

	bt.netblock = &netblock{
		name:   bt.name + "-IP-Handler",
		plugin: bt,
	}
	if err := r.RegisterHandler(&et.Handler{
		Plugin:       bt,

View on GitHub (pinned to 79299dce87)

Solutions

1. Verify DNS resolution works: dig bgp.tools A from the host.
2. Check network/firewall access to DNS resolvers; re-run the scan after connectivity is restored.
3. Retry the plugin start — the failure is often transient.
4. If it persists, confirm your resolver can resolve bgp.tools (some corporate resolvers block it) and use an alternative resolver.

Example fix

// before
rr, err := support.PerformQuery(ctx, "bgp.tools", dns.TypeA)
if err != nil {
    return fmt.Errorf("failed to obtain the BGPTools IP address: %v", err)
}
// after
rr, err := support.PerformQuery(ctx, "bgp.tools", dns.TypeA)
if err != nil {
    if support.IsTransient(err) { // or check ErrFailedMaxDNSAttempts
        return retry.Start(ctx) // retry startup instead of failing outright
    }
    return fmt.Errorf("failed to obtain the BGPTools IP address: %v", err)
}

// Pre-flight: ensure bgp.tools resolves before starting the plugin
addrs, err := net.LookupHost("bgp.tools")
if err != nil || len(addrs) == 0 {
    log.Fatal("cannot resolve bgp.tools; check DNS/network")
}

if err := plugin.Start(ctx); err != nil {
    if strings.Contains(err.Error(), "failed to obtain the BGPTools IP address") {
        time.Sleep(30 * time.Second)
        err = plugin.Start(ctx) // transient DNS failure: retry
    }
}

When it happens

Trigger: Plugin Start runs and support.PerformQuery(ctx, "bgp.tools", dns.TypeA) returns any of the resolver errors (ErrNameDoesNotExist, ErrFailedMaxDNSAttempts, unexpected response, wildcard detected), causing the wrapped error.

Common situations: Network/DNS outages during startup; firewalls blocking outbound DNS or port 53; bgp.tools resolution blocked on the host; transient resolver failures at boot time.

Related errors

• no resolver keys were found in the resolvers section
• brute forcing cannot be performed without DNS resolution
• active enumeration cannot be performed without DNS resolutio
• no valid resolvers were found
• name does not exist

AI-assisted analysis of owasp-amass/amass@79299dce87 (2026-09-06). Data as JSON: /api/errors/69d74201d69fcad1. Report an issue: GitHub.