DNS_PROBE_FINISHED_BAD_CONFIG

[#1]

Hi,

I am getting regular intermittent drops and slowdowns on all internet services, over wired connections.

browser connections from multiple different devices have started failing to basic services like www.google.com with eventual error of DNS_PROBE_FINISHED_BAD_CONFIG.  Refreshing this and within a minute this page and others will load without an issue for a while.

It has started in the past 2 weeks and is a daily issue now.  Obviously challenging as I am trying to run my business from home and i cant reliably connect to the internet, or other services like Zoom video chat.

I have tried webchat and callcentre support, and both seem to be offline now, contrary to the opening times listed in the covid update notification on the website.

Please help!

Kind regards,

Chris.

[#2]

I have also been experiencing this daily for the past 3-4 weeks. Generally everything works fine, but I find occassionally a website will take ages to load, sitting on 'resolving host' in the status bar for ages, and a few times per day I get DNS_PROBE_FINISHED_BAD_CONFIG. Hitting refresh a few times will get me in eventually. This is across all my devices and only occurs when I'm connected to my home lan (wired and wireless). If I e.g. use a 4g tether from my phone everything works fine.

[#3]

Hi @deox

If you haven't already done so, I would first advise having a run through our troubleshooting steps here:  https://www.plus.net/help/broadband/connection-troubleshooting/ and getting your router connected into the test socket for the time being as shown here: https://community.plus.net/t5/Library/Testing-From-The-Master-Socket/ba-p/1322242

If the issues then persist, please log a fault here with us: https://faults.plus.net and if you let us know once done, we can investigate further.

[#4]

Ticket created. ID: 202058839

[#5]

Thanks for getting back to us @grahamw1 I've tested your line tonight and the tests aren't showing any issues with the broadband signal going into your router. I'd recommend firstly carrying out a factory reset of your router by pushing a paperclip into the reset pinhole at the back for 20 seconds.

If you're still having issues, I'd then think we'd need to look at replacing the router. For a replacement router from us I'd advise ringing our customer options team on 0800 013 2632 as we may need to recontract you to send a new one out free of charge. Alternatively if you prefer to buy your own router, the settings found Here should help you set it up.

[#6]

Hi @Gandalf,

Thanks for the quick reply. I have already tried the router reset and all the other troubleshooting steps the fault reporter asks for.

I wouldn't expect it to be a router fault:

• Lots of other people on this forum are reporting the same issue.
• The issue seems to have started occurring at around the same time for everyone a couple of months ago.
• Switching to Google DNS servers makes it go away as several users have reported, which rules out anything in the last mile or within the household.

This indicates it is a problem with the PlusNet DNS servers themselves.

Graham

[#7]

Hi @grahamw1 

I'm still confident this is a router problem, because your devices will be contacting your router for the DNS servers. When you switch your devices onto Google's DNS servers, you're bypassing that particular function of the router.

I'm happy to be proven wrong though. Ultimately to try another router is the next step to getting to the bottom of the problem. 

[#8]

Try setting the Plusnet dns servers ( 212.159.6.9 & 10 ) directly on a  device instead of the google ones

That should determine whether it's the router or the dns servers...

[#9]

Hi,

I've been getting this frequently in the last week or so too. I performed a trace route and there was a fifteen second delay (step 3) before making contact with 132.hiper04.sheff.dial.plus.net.uk.

Traceroute has started…

traceroute: Warning: trello.com has multiple addresses; using 18.184.99.148
traceroute to trello.com (18.184.99.148), 64 hops max, 72 byte packets
1 bthub (192.168.1.254) 1.686 ms 1.783 ms 2.276 ms
2 172.16.14.161 (172.16.14.161) 4.514 ms 4.587 ms 5.016 ms
3 * * *
4 132.hiper04.sheff.dial.plus.net.uk (195.166.143.132) 6.938 ms 6.571 ms 6.674 ms

No manual settings. Router is auto configed.

*EDIT*

I've just retested and the 15 second delay is there when the issue isn't happening so I don't think the above is indicative of what is causing the DNS errors or slow DNS resolution.

[#10]

For the most part, DNS issues are mostly symptoms rather than a cause. Are you using a wired or wireless connection?

Some hops on a traceroute will time out and that’s OK as those servers will be prioritising traffic rather than responding back to you.