Solved: Some sites available only through proxy

[mattpi]

Hi all

I have recently been having a very annoying problem with my internet connection. I am not able to connect to some websites: the sites that are unavailable can not be accessed on any device connected to my home network (wireless or plugged directly into the router). I know that the problem does not lie with the sites themselves, since they are working for other people, and I know the sites are not blocking my IP, because when I reset the router, the problem sites become accessible but other sites become inaccessible (on all devices).

The problem isn't the router either: I've tried two, and the same problem has arisen with both. Moreover, I have established that the problem does not lie with DNS resolution. I have repeatedly flushed the DNS cache; DNS lookups work fine on the problem sites, but when I ping the given IP addresses I am getting some packet loss (not necessarily 100% loss). When I use a proxy, I can access the sites without any problem. Does anyone have any ideas?

 

[VictoriaiiCe]

Are you blocked from accessing these sites? Which sites only work with your proxy?

 

[mattpi]

The sites I can't access seem random, and change every time I reset the router (i.e. I can access the ones that wouldn't work before, but others become unavailable), so I'm not being blocked. I can also always access the problem sites via a proxy.

 

[TerryNet]

For a problem site, say www.someproblemsite.com, try (in a Command prompt)

tracert www.someproblemsite.com

If using a proxy you get a "nice" trace, where you can "see" the nodes getting closer to the destination and then ending at the destination but when not using the proxy the route seems to get lost or is much longer then likely your ISP has a routing problem. If this is the case you will need to patiently explain to the first tech person why you think so. When they don't understand politely and firmly ask to speak with a "tier 2" or a supervisor. Explain again and hopefully they will promise to look into it and it will get fixed in a day or less.

Not all nodes return pings, so sometimes the tracert is useless, as it just shows a whole bunch of time outs. The trick will be to find one that is good with the proxy but bad without.

Just for example here is a "nice" trace ...

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:\Users\Terry>tracert yahoo.com

Tracing route to yahoo.com [67.195.160.76]
over a maximum of 30 hops:

1 <1 ms <1 ms <1 ms 192.168.2.1
2 7 ms 11 ms 8 ms 10.20.55.1
3 22 ms 11 ms 11 ms 172.30.9.33
4 12 ms 10 ms * 172.30.9.165
5 15 ms 16 ms 17 ms 12.91.232.13
6 28 ms 25 ms 28 ms cr2.sl9mo.ip.att.net [12.122.152.202]
7 26 ms 27 ms 26 ms cr2.cgcil.ip.att.net [12.122.2.21]
8 23 ms 22 ms 25 ms cgr1.cgcil.ip.att.net [12.122.132.157]
9 22 ms 23 ms 23 ms te-8-3-10G.ar2.CHI2.gblx.net [64.208.110.145]
10 45 ms 47 ms 43 ms 208.178.62.126
11 45 ms 51 ms 54 ms xe-8-0-0.msr2.ac2.yahoo.com [216.115.108.137]
12 51 ms 51 ms 50 ms xe-8-2-0.clr4.ac4.yahoo.com [76.13.0.107]
13 50 ms 51 ms 52 ms te-9-1.bas-a2.ac4.yahoo.com [76.13.0.179]
14 52 ms 52 ms 44 ms ir1.fp.vip.ac4.yahoo.com [67.195.160.76]

Trace complete.

C:\Users\Terry>

 

[mattpi]

Thanks for the reply. Here is the result of a tracert on one of the problem sites:

C:\Windows\system32>tracert www.tvguide.co.uk

Tracing route to www.tvguide.co.uk [213.52.208.236]
over a maximum of 30 hops:

  1     2 ms     1 ms     1 ms  192.168.0.1
  2    33 ms    34 ms    33 ms  217.32.96.250
  3    31 ms    31 ms    31 ms  217.32.96.161
  4    31 ms    30 ms    30 ms  217.47.73.170
  5    31 ms    30 ms    30 ms  217.47.73.58
  6    32 ms    29 ms    30 ms  core2-pos12-2.sheffield.ukcore.bt.net [217.32.17
1.245]
  7    46 ms    41 ms    43 ms  core2-pos0-14-5-0.ealing.ukcore.bt.net [62.172.1
03.117]
  8    40 ms    40 ms    39 ms  peer2-xe10-1-0.telehouse.ukcore.bt.net [109.159.
254.116]
  9    40 ms    40 ms     *     linx1.telecityredbus.net [195.66.226.82]
 10    40 ms    39 ms     *     85.90.226.205
 11     *       39 ms     *     85.90.238.57
 12    40 ms    39 ms    39 ms  1-2-dist65-02.lon7.telecity.net [217.20.44.18]
 13     *        *        *     Request timed out.
 14     *        *        *     Request timed out.
 15     *        *        *     Request timed out.
 16     *        *        *     Request timed out.
 17     *        *        *     Request timed out.
 18     *        *        *     Request timed out.
 19     *        *        *     Request timed out.
 20     *        *        *     Request timed out.
 21     *        *        *     Request timed out.
 22     *        *        *     Request timed out.
 23     *        *        *     Request timed out.
 24     *        *        *     Request timed out.
 25     *        *        *     Request timed out.
 26     *        *        *     Request timed out.
 27     *        *        *     Request timed out.
 28     *        *        *     Request timed out.
 29     *        *        *     Request timed out.
 30     *        *        *     Request timed out.

Trace complete.

I don't know how to run a tracert through the proxy, though - I'm just using quickproxy on firefox

 

[TerryNet]

I don't know how to run a tracert through the proxy, though - I'm just using quickproxy on firefox

Nuts; neither do I. If you use the same proxy in Control Panel - Internet Options - Connections tab - LAN Settings... - maybe that will do the trick (I had assumed that it would, but not sure).

I can access that web site but get the same tracert result you do (disappears after 217.20.44.18), so I guess my idea is not going to work out anyhow. Sorry.

 

[mattpi]

Interestingly, I can still access www.tvguide.co.uk via the proxy, but using this online ping tool I get 100% packet loss from everywhere.

 

[TerryNet]

That site apparently doesn't return pings. Many don't.

 

[mattpi]

Ah, fair enough. I'm going to grit my teeth and ring the ISP to see if they can shed any light on the situation, once I've got through the inevitable half hour of them suggesting I turn everything off and on again.

 

[VictoriaiiCe]

Ah, fair enough. I'm going to grit my teeth and ring the ISP to see if they can shed any light on the situation, once I've got through the inevitable half hour of them suggesting I turn everything off and on again.

Best bet...Let us know how it goes.

 

[mattpi]

Hi - I was going to ring the ISP, but it turns out that the problem randomly fixed itself yesterday morning. Thanks for the help, sorry it ended up being a waste of time!

 

[VictoriaiiCe]

Awesome! You had as at a loss here! Glad to hear Would you mind marking this thread as solved? We'd greatly appreciate it.

 

[TerryNet]

Not a waste of time. I suspect that it indeed was some kind of routing problem and your ISP found and fixed it.