1.1.1.1 DNS not working from some IP addresses

Hello,
My ISP recently had a fibre cut and thereafter 1.1.1.1 and 1.0.0.1 DNS have not worked for me.
I have been in touch with my ISP and they say the DNS requests drop within the cloudflare network.
A network trace shows traffic drops at 196.60.8.198

f0:7c:c7:29:8a:5a 196.60.8.198 cloudflare.ixp.joburg ae3.115 none

Hi @alex120, we’re taking a look.

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@alex120 would you be able to traceroute again?

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Hello traced again from 102.134.22.90 and it fails at 154.66.247.141

Screenshot at 2023-08-17 11-52-39

Screenshot at 2023-08-17 12-11-31

Helo is it possible to get reverse trace to the IP 102.134.22.89?

Ok, so now it gets dropped in transit as well. The reverse path is different, it goes through AS37100, but can’t get a trace past that. We’ll try to restore the peering session and reach out to AS37662 to see if there’s an issue at the IXP.

3	ae-2-113.er-01-jnb.za.seacomnet.com (105.22.32.217)		10	0.509ms	0.278ms	0.625ms	0.115ms
4	ae-1.cr-01-jnb.za.seacomnet.com (105.16.29.1)		3	51.078ms	51.023ms	51.185ms	0.092ms
5	ce-0-0-11.cr-01-emg.za.seacomnet.com (105.16.8.226)		10	52.07ms	51.638ms	52.491ms	0.281ms
6	ce-0-0-1.cr-01-mba.ke.seacomnet.com (105.25.160.114)		10	51.214ms	50.762ms	51.545ms	0.334ms
7	xe-0-0-0-4.cr-01-nbo.ke.seacomnet.com (105.16.13.41)		10	53.974ms	52.021ms	54.963ms	1.017ms
8	xe-0-1-0.pp-01-nbo.ke.seacomnet.com (105.16.18.8)		10	51.001ms	50.944ms	51.133ms	0.064ms
9	***		0	0ms	0ms	0ms	0ms

Could you possibly try other IPs? e.g. 1.0.0.1 or 104.16.249.249 (cloudflare-dns.com)

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Also can you try if DNS over UDP or TCP work? Or if it is just ICMP? There are platform-specific debug commands in Have problems with 1.1.1.1? *Read Me First* - #9

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Thanks for the reply. I get the same results with 1.0.0.1 or 104.16.249.249.
Let me reach out to my ISP with the trace you did and try DNS over UDP/TCP.
Will let you know the results I get.
Thanks.

Yes, it happens to some domains. But there are some other issues as well, for example you are using a shared IPS address. what happens there, we sometimes copy the temporary shared address. So, make sure to use the IP Address.

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