diff --git a/cmd/cache.go b/cmd/cache.go
index c72af16..5e17fdd 100644
--- a/cmd/cache.go
+++ b/cmd/cache.go
@@ -2,7 +2,6 @@ package cmd
 
 import (
 	"dtool/prober"
-	"dtool/scheduler"
 	"dtool/utils"
 
 	"github.com/spf13/cobra"
@@ -11,6 +10,8 @@ import (
 var query_cnt int
 var inputfile string
 var outputfile string
+var goroutine_num int
+var controlled_domain string
 var cacheCmd = &cobra.Command{
 	Use:   "cache",
 	Short: "cache related test",
@@ -24,14 +25,16 @@ func cache_test(cmd *cobra.Command, args []string) {
 			prober.RecursiveCacheTest(args[0], query_cnt)
 		}
 	} else {
-		scheduler.CreateTask(prober.RecursiveCacheProbe, inputfile, outputfile, 10)
+		prober.CreateTask(prober.RecursiveCacheProbe, controlled_domain, inputfile, outputfile, goroutine_num)
 	}
 }
 
 func init() {
+	cacheCmd.Flags().StringVarP(&controlled_domain, "domain", "d", "echodns.xyz", "controlled domain")
 	cacheCmd.Flags().StringVarP(&inputfile, "input", "i", "", "input file(optional)")
 	cacheCmd.Flags().StringVarP(&outputfile, "output", "o", "", "output file(optional)")
 	cacheCmd.MarkFlagsRequiredTogether("input", "output")
 	cacheCmd.Flags().IntVarP(&query_cnt, "num", "n", 20, "number of queries in one test")
+	cacheCmd.Flags().IntVarP(&goroutine_num, "concurrency", "t", 150, "number of goroutine")
 	rootCmd.AddCommand(cacheCmd)
 }
diff --git a/cmd/record.go b/cmd/record.go
new file mode 100644
index 0000000..9ede8d7
--- /dev/null
+++ b/cmd/record.go
@@ -0,0 +1,47 @@
+package cmd
+
+import (
+	"dtool/prober"
+	"dtool/utils"
+
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+var record_input string
+var record_output string
+var record_type string
+var record_domain string
+var recordCmd = &cobra.Command{
+	Use:   "record",
+	Short: "get specific record response",
+	Long:  "get specific record response",
+	Run:   record_probe,
+}
+
+func record_probe(cmd *cobra.Command, args []string) {
+	if len(args) == 1 {
+		if utils.IsValidIP(args[0]) {
+			result, err := prober.SVCBProbeOnce(args[0], record_domain)
+			if err == nil {
+				if output_str, err := prober.OutputHandler(result); err == nil {
+					fmt.Println(output_str)
+				}
+			} else {
+				fmt.Println(err)
+			}
+		}
+	} else {
+		prober.CreateTask(prober.SVCBProbe, record_domain, record_input, record_output, 500)
+	}
+}
+
+func init() {
+	recordCmd.Flags().StringVarP(&record_input, "input", "i", "", "input file(optional)")
+	recordCmd.Flags().StringVarP(&record_output, "output", "o", "", "output file(optional)")
+	recordCmd.MarkFlagsRequiredTogether("input", "output")
+	recordCmd.Flags().StringVarP(&record_type, "type", "t", "A", "request record type")
+	recordCmd.Flags().StringVarP(&record_domain, "domain", "d", "example.com", "requested domain")
+	rootCmd.AddCommand(recordCmd)
+}
diff --git a/cmd/upstream.go b/cmd/upstream.go
index c40528b..a9f40ef 100644
--- a/cmd/upstream.go
+++ b/cmd/upstream.go
@@ -27,7 +27,7 @@ input target can be added as an argument or as a file
 
 func upstream(cmd *cobra.Command, args []string) {
 	if len(args) > 1 {
-		panic(errors.New("too many arguments!"))
+		panic(errors.New("too many arguments"))
 	} else if len(args) == 1 {
 		if utils.IsValidIP(args[0]) {
 			prober.Get_upstream_ip(args[0])
diff --git a/cmd/version.go b/cmd/version.go
deleted file mode 100644
index 3c6712b..0000000
--- a/cmd/version.go
+++ /dev/null
@@ -1,20 +0,0 @@
-package cmd
-
-import (
-	"github.com/spf13/cobra"
-)
-
-var versionCmd = &cobra.Command{
-	Use:   "version",
-	Short: "get server version with version.bind",
-	Long:  "get server version with version.bind chaos txt request",
-	Run:   version,
-}
-
-func version(cmd *cobra.Command, args []string) {
-
-}
-
-func init() {
-	rootCmd.AddCommand(versionCmd)
-}
diff --git a/dtool b/dtool
new file mode 100755
index 0000000..3f38d77
Binary files /dev/null and b/dtool differ
diff --git a/prober/cache_prober.go b/prober/cache_prober.go
index b8dd9af..94adeb0 100644
--- a/prober/cache_prober.go
+++ b/prober/cache_prober.go
@@ -6,6 +6,8 @@ import (
 	"strconv"
 	"strings"
 	"time"
+
+	"github.com/miekg/dns"
 )
 
 const query_num = 20
@@ -15,7 +17,7 @@ type CacheStruct struct {
 	dict   map[int]map[string]bool
 }
 
-func RecursiveCacheProbe(ip string) CacheStruct {
+func RecursiveCacheProbe(ip string, sld string) CacheStruct {
 	data := CacheStruct{ip, make(map[int]map[string]bool)}
 	stop := 0
 	time_now := strconv.FormatInt(time.Now().Unix(), 10)
@@ -24,7 +26,7 @@ func RecursiveCacheProbe(ip string) CacheStruct {
 			break
 		}
 		subdomain := strings.Join([]string{strings.Replace(ip, ".", "-", -1), "fwd", strconv.Itoa(i), time_now}, "-")
-		domain := subdomain + ".echodns.xyz."
+		domain := dns.Fqdn(subdomain + "." + sld)
 		res, err := utils.SendQuery(ip, domain)
 		if err != nil {
 			//fmt.Printf("Error sending query: %s\n", err)
@@ -49,7 +51,7 @@ func RecursiveCacheProbe(ip string) CacheStruct {
 func RecursiveCacheTest(ip string, num int) {
 	res := make(map[string]map[int][]string)
 	temp := make(map[int][]string)
-	data := RecursiveCacheProbe(ip)
+	data := RecursiveCacheProbe(ip, "echodns.xyz")
 	if len(data.dict) > 0 {
 		for cache_id := range data.dict {
 			for rdns := range data.dict[cache_id] {
diff --git a/prober/record_prober.go b/prober/record_prober.go
new file mode 100644
index 0000000..e976477
--- /dev/null
+++ b/prober/record_prober.go
@@ -0,0 +1,38 @@
+package prober
+
+import (
+	"dtool/utils"
+)
+
+type SVCBResult struct {
+	Ip       string             `json:"ip"`
+	Response utils.SVCBResponse `json:"response"`
+}
+
+func SVCBProbeOnce(ip string, domain string) (SVCBResult, error) {
+	result := SVCBResult{Ip: ip}
+	res, err := utils.SendSVCBQuery(ip, domain)
+	if err != nil {
+		return result, err
+	}
+	resp, err := utils.ParseSVCBResponse(res)
+	if err != nil {
+		return result, err
+	}
+	result.Response = resp
+	return result, nil
+}
+
+func SVCBProbe(ip string, domain string) SVCBResult {
+	result := SVCBResult{Ip: ip}
+	res, err := utils.SendSVCBQuery(ip, domain)
+	if err != nil {
+		return result
+	}
+	resp, err := utils.ParseSVCBResponse(res)
+	if err != nil {
+		return result
+	}
+	result.Response = resp
+	return result
+}
diff --git a/prober/result_handler.go b/prober/result_handler.go
index 35f85f7..470c922 100644
--- a/prober/result_handler.go
+++ b/prober/result_handler.go
@@ -26,6 +26,8 @@ func OutputHandler(data interface{}) (string, error) {
 		}
 		result[value.target] = temp
 		output_str, err = utils.ToJSON(result, "")
+	case SVCBResult:
+		output_str, err = utils.ToJSON(data, "")
 	}
 	return output_str, err
 }
diff --git a/scheduler/scheduler.go b/prober/scheduler.go
similarity index 72%
rename from scheduler/scheduler.go
rename to prober/scheduler.go
index 496851c..2ffe4a2 100644
--- a/scheduler/scheduler.go
+++ b/prober/scheduler.go
@@ -1,8 +1,7 @@
-package scheduler
+package prober
 
 import (
 	"bufio"
-	"dtool/prober"
 	"dtool/utils"
 	"fmt"
 	"os"
@@ -20,7 +19,7 @@ func output_process(output chan interface{}, file string, wg *sync.WaitGroup) {
 	writer := bufio.NewWriter(f)
 	for {
 		if data, ok := <-output; ok {
-			str, err := prober.OutputHandler(data)
+			str, err := OutputHandler(data)
 			if err != nil {
 				fmt.Printf("Error generating output: %s\n", err)
 				continue
@@ -37,10 +36,10 @@ func output_process(output chan interface{}, file string, wg *sync.WaitGroup) {
 	wg.Done()
 }
 
-func concurrent_execution[T any](fn func(string) T, input chan string, output chan interface{}, wg *sync.WaitGroup) {
+func concurrent_execution[T any](fn func(string, string) T, domain string, input chan string, output chan interface{}, wg *sync.WaitGroup) {
 	for {
 		if ip, ok := <-input; ok {
-			data := fn(ip)
+			data := fn(ip, domain)
 			output <- data
 		} else {
 			break
@@ -49,7 +48,7 @@ func concurrent_execution[T any](fn func(string) T, input chan string, output ch
 	wg.Done()
 }
 
-func CreateTask[T any](fn func(string) T, input_file string, output_file string, concurrent_num int) {
+func CreateTask[T any](fn func(string, string) T, domain string, input_file string, output_file string, concurrent_num int) {
 	input_pool := make(chan string, 500)
 	output_pool := make(chan interface{}, 500)
 	var probe_tasks sync.WaitGroup
@@ -58,7 +57,7 @@ func CreateTask[T any](fn func(string) T, input_file string, output_file string,
 	go utils.RetrieveLines(input_pool, input_file)
 	probe_tasks.Add(concurrent_num)
 	for i := 0; i < concurrent_num; i++ {
-		go concurrent_execution(fn, input_pool, output_pool, &probe_tasks)
+		go concurrent_execution(fn, domain, input_pool, output_pool, &probe_tasks)
 	}
 	store_tasks.Add(1)
 	go output_process(output_pool, output_file, &store_tasks)
diff --git a/prober/version_prober.go b/prober/version_prober.go
deleted file mode 100644
index 8219d21..0000000
--- a/prober/version_prober.go
+++ /dev/null
@@ -1 +0,0 @@
-package prober
diff --git a/utils/dns_utils.go b/utils/dns_utils.go
index 9b398ca..641968a 100644
--- a/utils/dns_utils.go
+++ b/utils/dns_utils.go
@@ -27,6 +27,15 @@ type DomainInfo struct {
 	NSList map[string][]string
 }
 
+type SVCBRecord struct {
+	Target string            `json:"target"`
+	Data   map[string]string `json:"value"`
+}
+
+type SVCBResponse struct {
+	Records []SVCBRecord `json:"records"`
+}
+
 func (e *WrongAnswerError) Error() string {
 	return fmt.Sprintf("Wrong Answer: %s", e.Message)
 }
@@ -39,11 +48,7 @@ func QuestionMaker(domain string, qclass uint16, qtype uint16) *dns.Question {
 // build a dns query message
 func QueryMaker(query QueryStruct) *dns.Msg {
 	msg := new(dns.Msg)
-	if query.Id < 0 {
-		msg.Id = dns.Id()
-	} else {
-		msg.Id = query.Id
-	}
+	msg.Id = query.Id
 	msg.RecursionDesired = query.RD
 
 	var query_name string
@@ -155,3 +160,58 @@ func SendVersionQuery(ip string) (*dns.Msg, error) {
 
 	return res, err
 }
+
+func SendSVCBQuery(ip string, domain string) (*dns.Msg, error) {
+	addr := ip + ":53"
+	query := QueryStruct{Id: dns.Id(), Qname: dns.Fqdn(domain), RD: true, Qtype: dns.TypeSVCB}
+	m := QueryMaker(query)
+
+	res, err := dns.Exchange(m, addr)
+
+	return res, err
+}
+
+func toSVCBKEY(key dns.SVCBKey) string {
+	switch key {
+	case dns.SVCB_MANDATORY:
+		return "mandatory"
+	case dns.SVCB_ALPN:
+		return "alpn"
+	case dns.SVCB_NO_DEFAULT_ALPN:
+		return "no_default_alpn"
+	case dns.SVCB_PORT:
+		return "port"
+	case dns.SVCB_IPV4HINT:
+		return "ipv4_hint"
+	case dns.SVCB_ECHCONFIG:
+		return "ech_config"
+	case dns.SVCB_IPV6HINT:
+		return "ipv6_hint"
+	case dns.SVCB_DOHPATH:
+		return "doh_path"
+	default:
+		return "unknown"
+	}
+}
+
+func ParseSVCBResponse(msg *dns.Msg) (SVCBResponse, error) {
+	response := SVCBResponse{Records: make([]SVCBRecord, 0)}
+	if len(msg.Answer) > 0 {
+		for _, rr := range msg.Answer {
+			if svcb, ok := rr.(*dns.SVCB); ok {
+				record := SVCBRecord{Data: make(map[string]string)}
+				record.Target = svcb.Target
+				for _, kv := range svcb.Value {
+					key := toSVCBKEY(kv.Key())
+					value := kv.String()
+					record.Data[key] = value
+				}
+				response.Records = append(response.Records, record)
+			}
+		}
+	}
+	if len(response.Records) > 0 {
+		return response, nil
+	}
+	return response, &WrongAnswerError{Message: "no valid SVCB records"}
+}
diff --git a/utils/httpdns_utils.go b/utils/httpdns_utils.go
index 11c891d..ba8ce8d 100644
--- a/utils/httpdns_utils.go
+++ b/utils/httpdns_utils.go
@@ -5,7 +5,7 @@ import (
 	"crypto/des"
 	"encoding/hex"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 )
 
@@ -75,7 +75,7 @@ func SendTencentHttpdnsQuery() {
 	}
 	defer resp.Body.Close()
 
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		fmt.Printf("read content failed. Error: %s\n", err)
 		return
@@ -102,7 +102,7 @@ func SendAlicloudHttpdnsQurey() {
 	}
 	defer resp.Body.Close()
 
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		fmt.Printf("read content failed. Error: %s\n", err)
 		return
diff --git a/utils/input_utils.go b/utils/input_utils.go
index a968f07..990eb15 100644
--- a/utils/input_utils.go
+++ b/utils/input_utils.go
@@ -24,7 +24,7 @@ func RetrieveLines(pool chan string, filename string) {
 		s = strings.Trim(s, "\n")
 		pool <- s
 		cnt++
-		if cnt%10 == 0 {
+		if cnt%1000 == 0 {
 			fmt.Println(cnt)
 		}
 	}
diff --git a/utils/other_utils.go b/utils/other_utils.go
index 9940a0c..af0a74b 100644
--- a/utils/other_utils.go
+++ b/utils/other_utils.go
@@ -6,8 +6,5 @@ import (
 
 func IsValidIP(ip string) bool {
 	res := net.ParseIP(ip)
-	if res == nil {
-		return false
-	}
-	return true
+	return res != nil
 }