尝试用 netty 写了一个简单的 dns server， dig 显示结果是正常的，但是浏览器， curl， wget 访问就访问不到了

我把虚拟机(win)的 dns 设置成我自己的 dnsserver 192.168.43.245,然后程序会把 aaa.1.tqtqtq.aaa 这个域名的 ip 解析成 192.168.43.245 ，192.168.43.245 的 80 端口上开了一个 web 服务，这样我认为访问 aaa.1.tqtqtq.aaa 的时候就会访问 192.168.43.245 的 web 服务。

这是本机 dig 的结果

dig aaa.1.tqtqtq.aaa @127.0.0.1 ; <<>> DiG 9.10.6 <<>> aaa.1.tqtqtq.aaa @127.0.0.1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57548 ;; flags: qr; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;aaa.1.tqtqtq.aaa. IN A ;; ANSWER SECTION: aaa.1.tqtqtq.aaa. 0 IN A 192.168.43.245 ;; Query time: 5 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Thu Jul 18 21:24:32 CST 2019 ;; MSG SIZE rcvd: 66 

然后用浏览器访问 aaa.1.tqtqtq.aaa 是访问不通的，比如在 ie 下返回的错误信息是

发生临时 DNS 错误。请尝试刷新页面。

错误代码: INET_E_RESOURCE_NOT_FOUND

直接访问 http://192.168.43.245/login 是访问的到的，证明 53 端口和 80 端口虚拟机都访问不到，dns 解析出了问题

在虚拟机 nslookup 的结果也有些不正常

DNS request timed out. timeout was 2 seconds. 服务器: UnKnown Address: 192.168.43.245 非权威应答: 名称: aaaa.1.tqtqtq.aaa Addresses: 192.168.43.245 192.168.43.245 

以下是 DNSHandler 的代码，没有找到问题出现在哪里，大家帮忙分析一下吧

public void channelRead0(ChannelHandlerContext ctx, DatagramDnsQuery query){ ByteBuf answerIP; int logID; DatagramDnsResponse respOnse= new DatagramDnsResponse(query.recipient(), query.sender(), query.id()); DefaultDnsQuestion dnsQuestion = query.recordAt(DnsSection.QUESTION); String cOnnectIP= query.sender().getHostName(); String domainRegex = "\\.\\d+\\."+domain.replace(".","\\.")+"\\.$"; String subDomain = dnsQuestion.name().replaceAll(domainRegex,""); String[] hd = dnsQuestion.name().replace('.'+domain+'.',"").split("\\."); try{ logID = Integer.parseInt(hd[hd.length-1]); }catch (NumberFormatException n){ return; } String ipRegex = "^((2(5[0-5]|[0-4]\\d))|[0-1]?\\d{1,2})(\\.((2(5[0-5]|[0-4]\\d))|[0-1]?\\d{1,2})){3}$"; String rebindRegex = "^((2(5[0-5]|[0-4]\\d))|[0-1]?\\d{1,2})(\\.((2(5[0-5]|[0-4]\\d))|[0-1]?\\d{1,2})){3}\\.((2(5[0-5]|[0-4]\\d))|[0-1]?\\d{1,2})(\\.((2(5[0-5]|[0-4]\\d))|[0-1]?\\d{1,2})){3}$"; if(Pattern.compile(rebindRegex).matcher(subDomain).matches()) { String[] s = subDomain.split("\\."); byte[] ip = new byte[4]; byte[] rebindIP = new byte[4]; for (int i = 0; i < s.length; i++) { if (i < 4) { ip[i] = (byte) Integer.parseInt(s[i]); } else { rebindIP[i - 4] = (byte) Integer.parseInt(s[i]); } } if (questionDomainMap.containsKey(dnsQuestion.name())) { answerIP = Unpooled.wrappedBuffer(questionDomainMap.get(dnsQuestion.name())); questionDomainMap.remove(dnsQuestion.name()); } else { answerIP = Unpooled.wrappedBuffer(ip); questionDomainMap.put(dnsQuestion.name(), rebindIP); } }else if(Pattern.compile(ipRegex).matcher(subDomain).matches()){ String[] s = subDomain.split("\\."); byte[] ip = new byte[s.length]; for(int i=0; i < s.length; i++){ ip[i] = (byte)Integer.parseInt(s[i]); } answerIP = Unpooled.wrappedBuffer(ip); }else{ answerIP = Unpooled.wrappedBuffer(new byte[] {(byte) 192, (byte) 168, 43, (byte)245}); System.out.println(dnsQuestion.name()); System.out.println(1); } DnsLog dnslog = new DnsLog(UUID.randomUUID().toString(),dnsQuestion.name().substring(0,dnsQuestion.name().length()-1),new Timestamp(System.currentTimeMillis()),connectIP,dnsQuestion.type().toString(),logID); dnsLogService.addDnsLog(dnslog); response.addRecord(DnsSection.QUESTION, dnsQuestion); DefaultDnsRawRecord queryAnswer = new DefaultDnsRawRecord(dnsQuestion.name(), DnsRecordType.A, 0, answerIP); response.addRecord(DnsSection.ANSWER, queryAnswer); ctx.writeAndFlush(response);