OT: Broadband problems

[Grumps]

Hi all. So, I don't think there is anything I can DIY about the issue I'm having, but I'll ask anyway ;)

As of last Thursday my internet access has gone from a really solid

37Mbps down to unusable at times. The problem is not that the router disconnects (it still sits there happily thinking it's connected at 40Mbps), but that there are very large delays even when simply browsing.

The main sites I'm using for testing are

and All I'm doing in the test is trying to load a page. Sometimes nothing happens and times out. Using fast.com shows a range of values from 0 to 37Mbps. It can cycle good and bad several times an hour, or just a couple of times a day. Re-booting, or power cycling gets it working again. But maybe that's just coincidental, as if you don't reset, it does seem to recover by itself.

I've done a quick tracert on the above addresses and when it works everything is sub 10ms. When it's in a bad mood, then some hops are several seconds.

I've replaced the router (twice), the microfilter, and this issue shows up on wired and wireless devices.

The last call to my ISP said that they had identified a non-specific fault and would send someone out. Is "non-specific" just their term for "we don't know what's going on"?

So, what sort of error would cause these symptoms? Thanks.

[Michael Chare]

Try the forums.thinkbroadband.com web site.

Step 1 is to publish the connection details of your router. i.e. attenuation, snr, connection speed etc.

[Grumps]

Thank you sir. I've done that and will now wait and see.

[John Rumm]

A line fault that is introducing a high burst error rate. Basically blocking error free transfer for periods of time. The ISP need to get it raised with openreach (assuming its FTTC, and not unbundled).

If you do a quiet line test (dial 17070, and select it from the voice menu), does the line sound continuously clear?

[Rob Morley]

Could be that your web access is running via a proxy service (transparent or otherwise) and the latency problem lies there rather than with your internet connection. Try some non-http speed tests, or explicitly setting a different proxy.

[Andy Burns]

That wouldn't explain the traceroute behaviour.

[Martin Brown]

Most likely is line noise from a tree rubbing the insulation off or a junction box compromised by ingress of water followed by daily freeze thaw action. There has been a spate of freeze induced ADSL failures round here this week (it has been down to -8C overnight). Plenty of the "waterproof" underground junction boxes are full of water :(

Opening a command window and trying ping google.com might shed some light. My guess is either you get perfect response

[Bob Henson]

Which ISP, Grumps? I have a similar problem with BT and the Homehub 6 router. The time-outs specifically led me to look at DNS problems, and changing Windows (you can't change the BT router) to use Google's DNS servers solved the problem. Extensive chats with BT and even them sending a new(?) replacement router found no clue, other than an indeterminate fault on the line which some of their operatives said was there and some of them said was not there - i.e. they had no idea. I still have no idea what the problem was (those more technical than me suggested it was a hardware/firmware problem) but have got round it completely by changing all my devices to use Google's DNS servers.

I don't know if you would want to change just as a test, but providing you make a note of what you change beforehand, you can easily put it back. If your router will let you change its DNS settings it's easier, of course, change them in the router and you only need to make one change for everything connected - I had to do each device separately.

The alternative - for me - with BT (which offers a good service otherwise) is to buy a router which is better and more configurable but as you have access to more than one router maybe one of them can be reprogrammed to Google's (or others - there are a few good servers about) settings to test things out.

[Dave Liquorice]

One in our line somewhere, could tell when the air temp was getting to 0 C as there would be a couple of ADSL2+(*) retrains. It's been stable for the last 4 days but then the temp hasn't been above freezing until midday yesterday...

Might be but more often than not these days sites are served from multiple shared IPs so without the proper URL the server doesn't know what to serve.

Some have them buried in the web interafce but more likely to need to telnet or ssh into a command line interface.

(*) Been able to move from 20CN ADSL2 (up to 8 Mbps) to ADSL2+ 21CN WBC (up to 24 mbps) not that it's made any noticeable difference to the speed. It might have gone up 1 Mbps to 6 Mbps, what is noticeable is the 30 second plus retrain period over the 8 of ADSL2.

[Tim+]

Now that was interesting. Despite having had Plusnet FTTC for the last year, I?ve never felt that general web browsing has been anywhere near as fast as it ought to have been.

My Technicolour router doesn?t seem to allow DNS changes but via this site https://uno.help/knowledge-base/article/how-to-change-dns-on-a-technicolor-tg582n I was able to change the LAN private settings to the google DNS settings.

Now I have no idea what all this means but web pages are loading a heck of a lot faster now. If I look at my basic internet setting though, the original DNS setting seem unchanged but as long as my browsing is way faster, I don?t care!

Tim

[Geoff Clare]

Given the time of year, one possibility is RF interference from some dodgy Christmas lights.

Did you or a neighbour turn on some Christmas lights last Thursday?

[Bob Henson]

I'm not sure what you mean by changing the LAN settings or where you changed them - but if you mean within Windows/Android/whatever then you are doing what I did by overriding the DNS settings locked into the router. That, if we had the same problem, could certainly result in big speed increases. Google's DNS servers are quick and you've removed a major bottleneck to the pages you browse.

I still can't work out why I (and many others) have this problem with BT/Plusnet's servers, because if there was something wrong with the actual remote servers they would have tens (hundreds?) of thousands of complaints (I assume they don't?) about it - but, like you, so long as everything is faster I don't care a tinkers cuss. I changed mine months back now and the actual line speed remains much faster (the actual connect speed was always fast), so I've given up trying to get any sense out of them.

[Bob Eager]

Plusnet said this (in reply to Tim, but probably worth a wider audience):

---------------------------------------- What you're seeing is less likely due to Google's servers being more responsive than ours, and more likely the result of you removing the router's DNS proxy from the equation when performing lookups.

i.e. before, you were doing this for each lookup:

client device > router > plusnet DNS resolver

Now, because you've told the router to assign Google's DNS to each client directly (rather than have proxy requests through the router), you're doing this:

client device > google DNS resolver

You'll probably find you have equal success assigning two of Plusnet's resolvers in the same way:

212.159.6.9 212.159.6.10 212.159.13.49 212.159.13.50

So it becomes:

client device > plusnet DNS resolver

Our DNS servers are without a doubt physically closer to you than Google's (from a routing perspective).

As an aside, you *can* change the DNS settings used by the router, however it needs to be done using telnet and the CLI -

------------------------------

[Brian Gaff]

Water in the cable damage somewhere, almost anything. I'm assuming its jolly old copper rubbish from bt. Brian

[Grumps]

Thanks all for your suggestions. It's too difficult replying to all as the line is up and down like a ...

The ISP is Sky. It's one of their fibre products, with copper to the house. The line test says that there is a little echo but no noise. The cables are all underground so no trees rubbing etc. Could be water in the cable, who knows. There are no local wacky Xmas lights. I have a man coming round on Sunday. Likely he'll have no clue, but I'll keep you posted.

[Bob Henson]

Very interesting, and refreshing to know that at least PlusNet admit the problem can and does happen - more than their parent BT does. It would be interesting to try doing what they suggest just to see if it does also solve the problem. I may do so, even though I have worked round it myself. However, "worked round" isn't good enough - surely someone at BT should have been interested in solving the problem?

When I first got my BT router with its included DNS settings all was well for a couple of months. One day it suddenly refused to connect to a website at all occasionally and timed out on many/most connections - seeming at random. It instantly recovered when I changed, after considerable research, to Google's DNS servers - so there was no doubt in which general area the problem lay.

No-one that I could find at BT could suggest any solution at all - most of them had little or no idea what I was talking about or pretended not to do so. The very first one was downright rude. It's hard to imagine how people so dim and inarticulate could be in customer service at all. It would have helped if they spoke reasonable English too. If they had made the suggestion that Plusnet (BT) made, I would have tried it immediately, albeit the extra stage had never been a problem before and it would still have provided no explanation.

Instead, they all told me nothing was wrong - presumably they thought I was hallucinating. One eventually sent me a new router - I thought that might help as it seemed to me it was a hardware and/or firmware issue. It didn't. I've since spoken to lots of folk online and off who are much more technically qualified then I am, but still no-one has an explanation.

[Bob Henson]

I've just read the whole of the thread from which you quoted and it does appear to give a partial answer to my question. The answer would appear to be the one I really didn't think possible with an organisation of that size and importance - BT's DNS server system is totally crap. Luckily, my suggested possible solution to Grumps was still correct - from what I considered to be my position of relative ignorance. However, it would appear that I am far better informed than BT's customer service staff.

I did ask and was told that it was impossible - but I wonder if it might be worth my while trying again to prise the information how to change my BT Homehub 6 router's DNS servers out of them? Not a snowball's chance in Hell, I suspect. Thanks for aiming me at that thread, anyway.

[Rob Morley]

Ah, I missed that bit.

[John Rumm]

You can always override the DNS servers used on your computer anyway by specifying them in the configuration of your network adaptor, rather than using what the router hands out via DHCP.

(some routers pass on the actual DNS server addresses they are configured with, others will pass their own address and then act as a proxy)

[Grumps]

Just if anyone is interested... The Sky/OpenReach engineer did NOT turn up, so none the wiser about the "non specific" fault they detected. But the problem turned out to be a laptop with a new install of OneDrive which was hogging the router during its initial sync. Has been sorted by setting max upload/download limits within OneDrive settings.