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Message 1 of 14

BT DNS Problems

Starting Monday Sep 30th our business website https://perrydogfield.com/ fails to resolve with the error: "DNS_PROBE_FINISHED_NXDOMAIN"

We have also received messages from people trying to use our website to book, saying that they can't access it. So this is not an issue specific to my setup.

On further digging it appears to be a BT / Plusnet DNS issue. 

These BT DNS servers do not resolve our website:

  • 62.6.40.178 
  • 194.74.65.68 
  • 194.74.65.69 
  • 194.72.9.38

These Plusnet DNS servers do not resolve our website:

  • 212.159.6.9
  • 212.159.6.10
  • 212.159.13.49
  • 212.159.13.50

Yet the following DNS servers all resolve perfectly:

  • 1.1.1.1 (Cloudflare)
  • 1.1.1.2 (Cloudflare)
  • 1.1.1.3 (Cloudflare)
  • 8.8.8.8 (Google)
  • 8.8.4.4 (Google)
  • 208.67.222.222 (OpenDNS)
  • 208.67.220.220 (OpenDNS)
  • 9.9.9.9 (Quad9)
  • 149.112.112.112 (Quad9)
  • 8.26.56.26 (Comodo)
  • 8.20.247.20 (Comodo)

I'm not a BT customer, I'm a Plusnet customer. I have already addressed this to Plusnet but so far there has been no solution provided. Since the BT Group owns Plusnet and it appears to be a BT DNS infrastructure issue, I thought I'd try posting it here too.

If any one could share any light on the potential cause or escalate this, that would be much appreciated.

Thanks!

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Message 2 of 14

Re: BT DNS Problems

You're not wrong I'm afraid:

 

C:\Users\naylor>nslookup perrydogfield.com 194.74.65.68
Server:  indnsc41.ukcore.bt.net
Address:  194.74.65.68

*** indnsc41.ukcore.bt.net can't find perrydogfield.com: Non-existent domain

C:\Users\naylor>nslookup perrydogfield.com 1.1.1.1
Server:  one.one.one.one
Address:  1.1.1.1

Non-authoritative answer:
Name:    perrydogfield.com
Address:  x.x.x.x

 

 

The same being replicated accross all those you mention.

Have you made any changes lately?

You could try changing the IP address in the record to an incorrect one then change it back to the correct one whilst reducing the TTL.

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BT900 | Nokia ONT | Ubiquiti ER-X | EETV Box Pro (IP Mode) | Unifi CK2 | 6x Unifi U6+ | 2x Unifi SAK Ultra
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Message 3 of 14

Re: BT DNS Problems

Thanks for taking a look. No changes at all before this started, and my host hasn't made any changes either. I have already tried changing the IP to an incorrect one and changing it back, along with reducing the TTL, but no joy. I have also changed the nameservers from my hosts (Krystal) cPanel nameservers to their Cloud nameservers and recreated all the records there. That was two days ago now. I don't really want to touch anything else now until next week, just to make sure I've given everything enough time to propagate. 

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Message 4 of 14

Re: BT DNS Problems

Yeah, you may want to now wait a few more days.

People do moan about BT DNS servers, notice it on here quite a bit, never quite as black and white as this though. I use my own DNS server at home which upstream is Cloudflare and Google, so I'm all good and can browse your lovely site.

Hopefully moving to the cloud service will resolve it.

Not that its of any help right now but I host all my domains with Cloudflare and never had an issue, just for a laugh I ran through all those BT and Plusnet ones you posted and everything resolves. One of my Domains is a VPN address and I use this all over the country to dial in and not once had it not resolve. Really impressed with Cloudflare bar their minor blip a few months back when 1.1.1.1 was down entirely.

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BT900 | Nokia ONT | Ubiquiti ER-X | EETV Box Pro (IP Mode) | Unifi CK2 | 6x Unifi U6+ | 2x Unifi SAK Ultra
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Message 5 of 14

Re: BT DNS Problems

Thanks so much for looking into this. It's quite frustrating as it's a new business and we now have people contacting us saying that they can't get on the website to book. Luckily we have another booking link that we can send them, but only if they contact us,  most won't bother. I'll definitely be trying Cloudflare next week if it's still not resolved. 

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Message 6 of 14

Re: BT DNS Problems

@starlink777 The problem you have may be caused by the same changes as in this very recent thread: Help! BT blocking a website i was building! - BT Community

There are a couple of work arounds that you could suggest as temporary solutions to your customers (and use yourself) but I think you will need to call Customer Services to get things  properly corrected. This does assume the cause is the same though.

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Message 7 of 14

Re: BT DNS Problems

My site isn't listed on any of the spam databases that I have checked, so I'm not sure if it's the same issue. 

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Message 8 of 14

Re: BT DNS Problems

Its not really a block issue, the DNS record literally doesnt exist on those name servers.

Last resort might be to migrate the domain to one of the big dogs.....

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BT900 | Nokia ONT | Ubiquiti ER-X | EETV Box Pro (IP Mode) | Unifi CK2 | 6x Unifi U6+ | 2x Unifi SAK Ultra
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Message 9 of 14

Re: BT DNS Problems

The symptoms described so far seem identical to those on the thread I highlighted, where I thought it was simply a DNS problem but turned out to be BT blocking the site as well. If you use Firefox you can select the secure DNS option and then select the DNS server of your choice (provided it supports secure DNS), or you could but the ip address of your server in the hosts file. Either of these options might allow you access to the site, but obviously not feasible for your customers.

You needs to report the problem to BT and/or try and get a Mod involved on this site and point them at both this thread and the other thread (assume it is relevant). 

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Message 10 of 14

Re: BT DNS Problems

Thanks. I know how to change my DNS to access the site, but like you mention this doesn't help customers visiting the site who are on BT / Plusnet / EE. I've changed the nameservers over to Cloudflare this morning to see if that makes any difference, so far it hasn't but it's early days. I have also reported this to BT and Plusnet. 

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