networking - Troubleshooting an unstable internet connection
2014-04
My MacBook Pro running OS X (10.9, but I had the same problem before) is connected to a Belkin router via WiFi and, using Virgin Media as the ISP, to the internet. The connection is extremely unstable – on some days, I get a ping timeout every few seconds. In addition, some domains seem to suffer general connectivity issues. For instance, I often find that while the youtube.com website loads, none of the videos (which are hosted on a separate domain) do. At other times, videos load but always fail to buffer, even though the actual connection speed is ok, even though I’ve disabled dash playback.
Since I’m living in a rented room and the ISP contract isn’t actually mine I’ve got only limited possibilities of addressing the problem. In particular, I have no access to the router configuration and my non tech savvy landlady, while sympathetic, is not in a great hurry to hand the problem over to the ISP’s customer support. What’s more, I seem to be the only person in the house experiencing these problems – but I can imagine that this is simply because I’m the only one who’s using the internet continuously.
I’m searching for specific tests that might be able to pinpoint – and ideally solve – the problem. So far all I’ve managed to do is establish that Virgin is routing my traffic in mysterious ways. Here’s an excerpt from traceroute google.co.uk
. It’s worth mentioning that the host name doesn’t seem to matter a lot, the trace route is always the same.
traceroute: Warning: google.co.uk has multiple addresses; using 62.254.36.148
traceroute to google.co.uk (62.254.36.148), 64 hops max, 52 byte packets
1 (192.168.2.1) 1.112 ms 1.300 ms 2.359 ms
2 10.100.32.1 (10.100.32.1) 11.926 ms 10.217 ms 24.987 ms
3 cmbg-core-1a-ae3-610.network.virginmedia.net (80.1.202.93) 28.809 ms * 66.653 ms
4 popl-bb-1b-ae16-0.network.virginmedia.net (212.43.163.141) 13.759 ms 126.504 ms 20.472 ms
5 nrth-bb-1b-et-010-0.network.virginmedia.net (62.253.175.57) 28.357 ms 16.398 ms 42.387 ms
6 nrth-bb-1c-ae1-0.network.virginmedia.net (62.253.174.110) 27.441 ms 15.622 ms 12.044 ms
7 lutn-icdn-1-ae0-0.network.virginmedia.net (62.253.175.82) 16.678 ms 28.463 ms 28.253 ms
8 * * *
9 * * *
10 * * *
^C
If I let it, this goes on until the end of time. It never seems to reach a destination. Is this normal? A friend living in the same town who is also with Virgin Media has a more conventional traceroute output: 7 hops to google.co.uk, all of which send the ICMP TIME_EXCEEDED response.
The obvious fix – rebooting the router – doesn’t seem to help. As far as I can tell, the WiFi connection is stable (I can always ping the router) so the problem is further downstream.
I’ve tried using an alternative DNS before (OpenDNS) but if anything, this made things worse. In fact, it made all Google services nigh unreachable.
As you said your problem is further down stream.
Your traceroute should be getting through, it looks like a Virgin issue with a combination of DNS issues as well, and maybe some sort of filtering on UDP packets.
To further troubleshoot this issue, I would do traces to youtube when you are having issues and compare the ping as well as trace times to the google IP's as well as 8.8.8.8 which are the google dns servers. I would also then check the traces to the videos you are having issues accessing.
If there are obvious routing issues as there seem to be (loops) I would send a few emails to Virgin.
I have found in the past that when I point issues like that out, I don't get a reply but within a few days the issues resolve themselves. ;-)
A trace to the IP you gave is not working for me from the US: 62.254.36.148 when I use UDP traceroute
When I use traceroute -I the trace gets through:
$ traceroute -I 62.254.36.148
traceroute to 62.254.36.148 (62.254.36.148), 64 hops max, 72 byte packets
1 192.168.2.1 (192.168.2.1) 4.473 ms 1.630 ms 1.805 ms
2 hlrn-dsl-gw07.hlrn.qwest.net (207.225.112.7) 25.282 ms 24.626 ms 23.868 ms
3 hlrn-agw1.inet.qwest.net (71.217.188.49) 24.561 ms 23.959 ms 23.544 ms
4 lap-brdr-03.inet.qwest.net (67.14.22.78) 85.451 ms 59.270 ms 63.060 ms
5 63.146.27.146 (63.146.27.146) 57.686 ms 60.734 ms 57.675 ms
6 xe-1-2-0.man11.ip4.tinet.net (141.136.107.49) 183.289 ms 181.508 ms 180.518 ms
7 telewest-communications-group-gw.ip4.tinet.net (77.67.65.142) 192.229 ms 306.696 ms 307.004 ms
8 leed-bb-1b-et-710-0.network.virginmedia.net (62.253.175.26) 177.170 ms 176.597 ms 177.369 ms
9 leed-bb-1c-ae1-0.network.virginmedia.net (62.253.174.26) 185.542 ms 186.098 ms 184.577 ms
10 nrth-bb-1c-ae9-0.network.virginmedia.net (62.253.174.122) 192.738 ms 192.278 ms 193.189 ms
11 lutn-icdn-1-ae0-0.network.virginmedia.net (62.253.175.82) 193.644 ms * *
12 m148-mp2.cvx1-a.lis.dial.ntli.net (62.254.36.148) 194.769 ms 194.916 ms 199.594 ms
When I do a dns lookup and trace to google.co.uk I get a Denver based address which is where I am at.
Can you post a trace to the google dns server 8.8.8.8?
Here is my output:
ff-macbook-pro:~ $ traceroute -d google.com
traceroute: Warning: google.com has multiple addresses; using 74.125.225.161
traceroute to google.com (74.125.225.161), 64 hops max, 52 byte packets
1 192.168.2.1 (192.168.2.1) 3.497 ms 2.813 ms 2.908 ms
2 hlrn-dsl-gw07.hlrn.qwest.net (207.225.112.7) 25.471 ms 33.509 ms 26.338 ms
3 hlrn-agw1.inet.qwest.net (71.217.188.49) 28.182 ms 32.209 ms 27.871 ms
4 dvr-edge-13.inet.qwest.net (67.14.24.93) 25.827 ms 25.075 ms 34.959 ms
5 67.134.166.226 (67.134.166.226) 25.509 ms 28.257 ms 35.462 ms
6 72.14.234.59 (72.14.234.59) 27.451 ms 27.234 ms 24.206 ms
7 209.85.251.9 (209.85.251.9) 25.893 ms 25.906 ms 25.264 ms
8 den03s05-in-f1.1e100.net (74.125.225.161) 26.085 ms 27.530 ms 33.049 ms
-macbook-pro:~ $
-macbook-pro:~ $
-macbook-pro:~ $
-macbook-pro:~ $ traceroute -d 62.254.36.148
traceroute to 62.254.36.148 (62.254.36.148), 64 hops max, 52 byte packets
1 192.168.2.1 (192.168.2.1) 5.426 ms 1.308 ms 2.052 ms
2 hlrn-dsl-gw07.hlrn.qwest.net (207.225.112.7) 24.993 ms 23.944 ms 29.122 ms
3 hlrn-agw1.inet.qwest.net (71.217.188.49) 24.853 ms 26.421 ms 25.547 ms
4 lap-brdr-03.inet.qwest.net (67.14.22.78) 58.722 ms 66.810 ms 60.422 ms
5 63.146.27.146 (63.146.27.146) 58.612 ms 65.550 ms 60.771 ms
6 xe-1-0-0.man11.ip4.tinet.net (89.149.181.38) 182.197 ms 192.739 ms 188.749 ms
7 telewest-communications-group-gw.ip4.tinet.net (77.67.65.142) 193.114 ms 192.274 ms 186.872 ms
8 brhm-bb-1b-et-400-0.network.virginmedia.net (62.253.175.69) 187.353 ms
leed-bb-1b-et-710-0.network.virginmedia.net (62.253.175.26) 184.031 ms
brhm-bb-1b-et-010-0.network.virginmedia.net (62.253.175.73) 186.819 ms
9 nrth-bb-1b-et-410-0.network.virginmedia.net (62.253.175.78) 194.633 ms *
nrth-bb-1b-et-400-0.network.virginmedia.net (62.253.175.46) 194.617 ms
10 nrth-bb-1c-ae10-0.network.virginmedia.net (62.253.174.146) 193.762 ms * *
11 lutn-icdn-1-ae0-0.network.virginmedia.net (62.253.175.82) 202.066 ms 203.886 ms *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
^C
I have a Windows 7 machine that also has Ubuntu on it. Yesterday the NIC spontaneously crapped out. I went and got a Dynex PCI NIC and set it up, my computer now finds networks but lists them as "unidentified" with either "no internet access" or "no network access".
I can't seem to detect other computers on the network either, so I do not believe it is even properly connecting to the LAN.
Things I have tried:
Reinstalling/Updating NIC drivers.
Restarting Router
Restarting Modem
Hooking desktop directly up to the modem's output (no router in between)
ipconfig /flushdns
netsh winsock reset
ipconfig /release (gets an error, doesn't complete) ipconfig /renew (gets an error, doesn't complete)
Trying to connect on Ubuntu (NIC is detected succesfully, but no connection is made)
Running the computer on an entirely different network (same ISP though, but one is a business connection and one is a personal/home connection)
setting up ipv4 info manually with static ip
connecting via WiFi adapter
connecting via Android phone w/ internet passthrough feature (detected as a network adapter, drivers installed, network found, exact same issues as with the NIC and the usb adapter)
WiFi on different networks
The only thing I can think of at this point is maybe a service running on the computer that is causing issues. However, I did a restore to 2 days before the issue began, and the problem is the exact same, not to mention it won't connect on ubuntu either.
Any ideas?