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Connections to certain servers unavailable

HolaPussycat
Grafter
Posts: 50
Registered: ‎29-03-2011

Connections to certain servers unavailable

We've had some strange connection problems since around 11:30 AM BST, where we cannot connect to most websites:
At first, I didn't realise that I was able to make some connections and I simply reconnected.
We're able to connect to google.co.uk and services such as Skype / Live Messenger, but not, for example, to facebook.com, twitter.com, or, wait for it... plus.net
A tracert to those places, is showing sensible times, eg:
tracert plus.net
Tracing route to plus.net [212.159.8.2]
over a maximum of 30 hops:
1 1 ms <1 ms 1 ms 10.0.0.2
2 31 ms 29 ms 28 ms lo0-central1.pcl-ag04.plus.net [195.166.128.241]
3 28 ms 28 ms 28 ms gi1-10-411.pcl-gw01.plus.net [84.92.6.224]
4 42 ms 42 ms 41 ms po5.ptn-gw01.plus.net [212.159.1.131]
5 42 ms 41 ms 50 ms gi3-0.pih-cr1.plus.net [212.159.1.177]
6 68 ms 42 ms 41 ms if25.pih-lb03.plus.net [212.159.0.17]
7 42 ms 42 ms 41 ms portal.plus.net [212.159.8.2]
Trace complete.
but we're not getting a response back in the browser (we're checking in, among others: FF 3.6.16, FF 4.0, IE 8, Chrome 10.0.648.204, across more than one machine)
To make sure it wasn't some badly cached DNS lookups, the DNS cache was flushed (I noted that I had my DNS set to use 8.8.8.8 as secondary to the router, using the plus.net DNS 212.159.6.10)
So, for the amusing part; I'm now posting this from my neighbours' plus.net connection, which can connect to everything perfectly happily.
Comparing the trace routes I've done so far; these are the hops that are different, and must be causing the problem:
lo0-central1.pcl-ag04.plus.net [195.166.128.241]
gi1-10-411.pcl-gw01.plus.net [84.92.6.224]
as the neighbours' working connection is using:
lo0-central3.pcl-ag06.plus.net [195.166.130.48]
gi7-7-631.pcl-gw01.plus.net [84.93.254.145]
So what would be causing a route to be traceable, but no connection being made by the browser? Is this part of the changes to the bandwidth throttling that has gone wrong? Tested different connection types on different ports (obviously 80, 110 and 443). FTP (21) was able to connect, but then wasn't returning a file list. SSH (22) was working, but is obviously a very limited amount of information being sent and received.
I'm sure there won't be many complaints, as nobody can connect to community.plus.net, through their connection!
James
13 REPLIES 13
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

I have been seeing the same issue, where most websites work normally but in particular plus.net and eBay hang as if the DNS lookup got stuck, even though other active browser tabs (to other websites) are still working normally !.
However if I wireshark the connection, I can see the correct DNS responses (form my local DNS server), but the hung connections are full of TCP retransmissions !.
Hopping gateways nearly always fixes it, and it only happens once or twice a day, but is VERY annoying if you are trying to bid on eBay when the page hangs !
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT
HolaPussycat
Grafter
Posts: 50
Registered: ‎29-03-2011

Re: Connections to certain servers unavailable

How long have you been suffering Purleigh? I made a support ticket at 1:40 for this, but haven't yet had a response, and the support system was truncating my question as soon as it got to the less than,so I had to edit that out and resend it.
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

It only appeared maybe two weeks ago when the hang-ups were quite frequent each day, but has been significantly better since the switches were reloaded a few days ago (as reported by Bob), and I have only seen it once today, and it might have been twice yesterday.
At the time I couldn't be bothered to report it as most of these sorts of problems usually just disappear after a few days, and also I could not capture any relevant evidence to put in a ticket - so I was watching what was going on to be able to report something constructive.  It really did behave like failed lookup from an unresponsive DNS server, but as I said before my Wireshark traces proved that my DNS was working perfectly. Alternatively I thought maybe it was just a coincidence that plus.net and eBay were having connection difficulties, as most other sites worked as normal, and I even kept internet radio audio streaming running so I could listen for possible connection dropouts - but there weren't any - even when eBay hung in another browser tab.
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT
HolaPussycat
Grafter
Posts: 50
Registered: ‎29-03-2011

Re: Connections to certain servers unavailable

I'm glad it wasn't just me that went straight to the DNS as being the problem; you're absolutely right, it's like certain sites aren't resolving, but we've proved that's not the problem.
It seems to be an odd range of sites working and not working. Annoyingly for me, this has cost me a couple hundred quids worth of work today, chasing around, trying to get a connection and reporting the problem, but still without any response from plus.net.
Community Veteran
Posts: 6,340
Thanks: 92
Fixes: 4
Registered: ‎08-01-2008

Re: Connections to certain servers unavailable

I just got a failure on bbc.co.uk, IE says:
Internet Explorer cannot display the webpage
and a ping request says it 'could not find host'
Other tabs / sites working normally (including this one)
I assume this is a DNS issue, my router is set up to use the default Plus Net DNS servers.
Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.
Community Veteran
Posts: 6,340
Thanks: 92
Fixes: 4
Registered: ‎08-01-2008

Re: Connections to certain servers unavailable

OK, mine is a differnt issue: http://community.plus.net/forum/index.php/topic,94737.0.html
Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.
HolaPussycat
Grafter
Posts: 50
Registered: ‎29-03-2011

Re: Connections to certain servers unavailable

Just spoken to Martin Driver on the phone; supremely helpful, I should know to just phone up with problems like this in the future.
One more router reset (using Google DNS on the router, not just this machine) and now I'm being routed via lo0-central1.thn-ag2.plus.net [195.166.128.229]
Tracing route to plus.net [212.159.8.2]
over a maximum of 30 hops:
  1    1 ms    <1 ms    <1 ms  router [10.0.0.2]
  2    28 ms    28 ms    28 ms  lo0-central1.thn-ag2.plus.net [195.166.128.229]
  3    31 ms    28 ms    27 ms  gi1-10-211.thn-gw1.plus.net [84.92.6.192]
  4    42 ms    41 ms    42 ms  po6.ptn-gw01.plus.net [212.159.1.137]
  5    41 ms    42 ms    41 ms  gi3-0.pih-cr1.plus.net [212.159.1.177]
  6    41 ms    41 ms    41 ms  if25.pih-lb03.plus.net [212.159.0.17]
  7    43 ms    42 ms    41 ms  portal.plus.net [212.159.8.2]
Trace complete.
Which is working nicely right now (though of course, it is after midnight!)
Walker, we suffered the bbc.co.uk problem while we were testing on the phone - just to throw a red herring in there for us!
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

For the last ten minutes I was starting to struggle to display complete eBay pages, without stalling or incomplete pages.
Then was having trouble maintaining an ftp connection with my Force9 webspace,
Did a speed test that showed my connection was a down to a meg (from a usual 6.5Mbps).
Checked which gateway I was connected to - "You are currently connected to the gateway known as ptn-ag04."
Did a router software disconnect - connect, to jump gateways.
Checked which gateway I was connected to - "You are currently connected to the gateway known as ptn-ag01."
Ran another speed test, now back to above 5Mbps.
Normal stability has returned, eBay works again, ftp link to Force9 now holds.
Not impressed ! - this is happening too frequently !!!  Angry
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

Here we go again  Angry
Web browsing just slowed to a crawl.
Router showing normal stats and synced at 8128Kbps.
Did the router disconnect/connect sequence FIVE TIMES to find a gateway that would speed test at over 3Mbps (where 6.5Mbps is normal on the same router stats)
Maybe it's time to light some more central pipes ?  :crazy:
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

I have just checked the packet drop graphs http://www.plus.net/support/service/network_performance/broadband_packets_drop.shtml
is that page working ? - as every value on every gateway is ZERO ! - not seen that happen before  Huh
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT
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Registered: ‎14-04-2007

Re: Connections to certain servers unavailable

They've been like that for some time I believe.

Customer and Forum Moderator. Windows 10 Firefox 72.0.2 (64-bit)

Life is tough enough without adding Linux into the mix.
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

Now that the graphs have moved on a couple of hours, there was a spike in "Platform QoS 20CN - QoS Drops (total)" just at the same time when my connection was struggling !
http://www.plus.net/support/service/network_performance/broadband_bandwidth_usage.shtml
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT
Community Veteran
Posts: 5,569
Thanks: 349
Fixes: 5
Registered: ‎11-08-2007

Re: Connections to certain servers unavailable

Web browsing just dropped form normal to almost nothing again, router stats normal, did disconnect/reconnect to jump to "thn-ag3" and full speed resumed !    Angry
Plusnet FTTC 80/20 IPv4/30, Hurricane Electric 6in4 IPv6/48, Pulse8 landline & calls, SamKnows 600N
Vigor 130 modem, pfSense 2.4.4-p3 router, 5 WAPs, Devolo dLAN 500, Gigaset N300A-IP VoIP DECT