owasp-amass/amass · error

failed to obtain the BGPTools IP address: %v

Error message

failed to obtain the BGPTools IP address: %v

What it means

The bgptools whois plugin's Start resolves the IP address of the bgp.tools DNS name before fetching BGP-related data. It returns this wrapped error when the DNS A-record query itself fails (support.PerformQuery returns err). It distinguishes the query-error case from the empty-answer case, which returns a plain error with the same text but no %v detail.

Source

Thrown at engine/plugins/whois/bgptools/plugin.go:64

			Name:       "BGP.Tools",
			Confidence: 100,
		},
	}
}

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,
	}

View on GitHub (pinned to 79299dce87)

Solutions

1. Verify network/DNS connectivity from the host (e.g. dig bgp.tools A)
2. Check firewall/egress rules allow DNS and outbound queries to bgp.tools
3. Retry with backoff — the failure may be transient; the 1-minute context may be too tight
4. Inspect the wrapped %v error detail to distinguish NXDOMAIN vs timeout vs network failure
5. Update the miekg/dns usage or resolver config if the local resolver is misconfigured

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
var rr []dns.RR
err := retry(3, time.Second, func() error {
    var e error
    rr, e = support.PerformQuery(ctx, "bgp.tools", dns.TypeA)
    return e
})
if err != nil {
    return fmt.Errorf("failed to obtain the BGPTools IP address after retries: %v", err)
}

// Go: pre-check DNS resolution before starting the plugin
if net.ParseIP(os.Getenv("BGPTOOLS_IP")) == nil {
    addrs, err := net.LookupHost("bgp.tools")
    if err != nil || len(addrs) == 0 {
        return fmt.Errorf("bgp.tools not resolvable, check DNS/network: %v", err)
    }
}

func isDNSQueryFailure(err error) bool {
    return err != nil && strings.Contains(err.Error(), "failed to obtain the BGPTools IP address")
}

if err := plugin.Start(context.Background()); err != nil {
    if isDNSQueryFailure(err) {
        log.Warn("bgp.tools unreachable, skipping plugin: %v", err)
        return nil // degrade gracefully instead of failing the run
    }
    return err
}

When it happens

Trigger: Calling Start when support.PerformQuery(ctx, "bgp.tools", dns.TypeA) returns a DNS lookup error: no network connectivity, DNS resolver failure, the name bgp.tools not resolving, or the query context (1-minute timeout) expiring.

Common situations: Sandboxed/offline environments or blocked egress DNS; corporate firewalls/DNS filtering blocking bgp.tools; resolver misconfiguration in containers; transient DNS outages or timeout under heavy load.

Related errors

• failed to obtain the Public DNS csv file at %s: %v
• 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

AI-assisted analysis of owasp-amass/amass@79299dce87 (2026-09-06). Data as JSON: /api/errors/8c6a67c3ee4a358d. Report an issue: GitHub.