DNS 查询

复制import socket
import dns.resolver

# 查询 A 记录（IPv4 地址）
hostname = "example.com"
try:
    answers = dns.resolver.resolve(hostname, 'A')
    for rdata in answers:
        print(f"A: {rdata.address}")  # 输出 IPv4 地址
except dns.resolver.NoAnswer:
    print("无 A 记录")
except dns.resolver.NXDOMAIN:
    print("域名不存在")

# 查询 MX 记录（邮件服务器优先级与主机）
try:
    answers = dns.resolver.resolve(hostname, 'MX')
    for rdata in answers:
        print(f"MX: priority={rdata.preference}, host={rdata.exchange}")
except dns.resolver.NoAnswer:
    print("无 MX 记录")

复制package main

import (
	"fmt"
	"net"
)

func main() {
	hostname := "example.com"

	// 查询 A 记录（IPv4）
	ips, err := net.LookupHost(hostname)
	if err != nil {
		fmt.Println("查询失败:", err)
		return
	}
	for _, ip := range ips {
		fmt.Println("A:", ip)
	}

	// 查询 MX 记录
	mxs, err := net.LookupMX(hostname)
	if err != nil {
		fmt.Println("MX 查询失败:", err)
		return
	}
	for _, mx := range mxs {
		fmt.Printf("MX: priority=%d, host=%s\n", mx.Pref, mx.Host)
	}

	// 查询 TXT 记录
	txts, err := net.LookupTXT(hostname)
	if err != nil {
		fmt.Println("TXT 查询失败:", err)
		return
	}
	for _, txt := range txts {
		fmt.Println("TXT:", txt)
	}
}

复制const dns = require('dns');

const hostname = 'example.com';

// 查询 A 记录（IPv4）
dns.resolve4(hostname, (err, addresses) => {
  if (err) {
    console.error('A 记录查询失败:', err.code);
    return;
  }
  addresses.forEach(addr => console.log('A:', addr));
});

// 查询 MX 记录
dns.resolveMx(hostname, (err, mxRecords) => {
  if (err) {
    console.error('MX 查询失败:', err.code);
    return;
  }
  mxRecords.forEach(mx => console.log(`MX: priority=${mx.priority}, host=${mx.exchange}`));
});

// 查询 TXT 记录
dns.resolveTxt(hostname, (err, txtRecords) => {
  if (err) {
    console.error('TXT 查询失败:', err.code);
    return;
  }
  txtRecords.forEach(txt => console.log('TXT:', txt.join(' ')));
});