How to force DNS requests using tcp protocol!

Hardware MikroTik hardware general
1

Hello


I set /ip dns server = 8.8.8.8, The RB751 default using udp protocol and Google DNS session.

But udp/53 in China have been contaminated, the ip address returned is false.

We test tcp/53 request to Google DNS query, the results returned are correct.

But how to force the RB751 to use tcp protocol and Google DNS session it?

Thanks!

2

Deleted because not related.

3

Hello Dobby

My ISP has a DNS server, but that is contaminated dns server.

If use isp’s dns, often get false results, they prohibit access to certain foreign sites.

Now I did not find the way how to force the RB751 tcp protocol and Google DNS session.

Steven

4

Is your isp not doing a nat redirect to force you to use theirs despite your settongs?

5

Hi TheWiFiGuy

Dns server can freely choose.

But network operators monitoring / interference port 53/udp, if you visit a site that they do not want, you get the ip address is false.

If to use port53/tcp and Google DNS seems everything is normal.

Steven

6

Deleted because not related.

7

I don’t think you can force requests to be TCP in a Mikrotik router.

I can think of a couple of ways to sort your issue,

  1. Run your own DNS resolver on a Linux box - you could even try metarouter. You may be able to force Bind9 to use TCP requests.

or

  1. Find a friendly server not too distant from China (latency) and open a VPN tunnel to it then use the tunnel to access the Google DNS 8.8.8.8 etc. Add /32 routes to your Mikrotik pointing to the PPTP/SSTP/IPSEC tunnel for 8.8.8.8 and other server IP addresses.

regards

Andy

8

Hi Andy / uksy29

Thank you for the suggestion!

Now I have to use the first program to use dnsforwarder (Chinese programmers write software), mandatory use tcp protocol to resolve.

The second program I originally used, but the low efficiency of this method after vpn, slower.

Originally, I was hoping to solve this problem directly RB751, but now it seems impossible.

Steven

19.DEC