Frustrated that I don't UNDERSTAND why my network times out - Page 3

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Re: Frustrated that I don't UNDERSTAND why my network times out
On Wed, 09 Oct 2013 11:18:19 +0000, billy wrote:
Quoted text here. Click to load it


You might try  
 traceroute -I centos.org

Re: Frustrated that I don't UNDERSTAND why my network times out
Quoted text here. Click to load it


That's a good starting point, yes. Now you need to see whether your web
browser can access centos.org. If it does, increase the MTU until it
breaks and then back it off a little.

If it still can't access centos.org, even though you've got your MTU
down at 500 then the chances are that this suggestion is inappropriate
for your situation.

Chris

Re: Frustrated that I don't UNDERSTAND why my network times out
On Wed, 09 Oct 2013 19:27:40 +0100, Chris Davies wrote:

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The MTU setting made no difference to the web situation.
The ONLY things that seem to work are:
a) Go to my neighbor's wireless setup
b) Use TOR

It's almost as if my IP address is being blocked by
that penultimate router.

Is that possible?


Re: Frustrated that I don't UNDERSTAND why my network times out
Quoted text here. Click to load it

Of course it is possible.  

Quoted text here. Click to load it

Re: Frustrated that I don't UNDERSTAND why my network times out
David Hough wrote:

Quoted text here. Click to load it

While I definitely value the help, part of why I am  
frustrated is that I don't UNDERSTAND the problem, and,  
as such, I consider ping a diagnostic tool.  

The point being, the ping isn't the problem (it's just
one way of showing the problem).

So, even if I get the ping to work, it still does nothing
to solve the problem (although it may explain a bit).

Since the problem manifests itself in the inability to  
connect via port 80 (i.e., the web), I have previously  
doubted the way I'm running ping has anything to do with it.

To me, in my simple mind, trying to get the ping to work is
sort of like having an engine misfire, and then I try all
sorts of options on my voltmeter to get it to give me a  
good reading.

Whether or not I get a good reading on the voltmeter, I  
still have the misfire.  

Back to the specifics, whether or not I get a good reading
on the ping, I still have the web failing to connect.  

I'm not saying ping isn't a great DIAGNOSTIC tool.

I'm just asking how a ping -M is going to help me UNDERSTAND
why I can't connect via the web to centos.org?

Nonetheless, in the next post, I'll post my ping results
(in the hope that it helps to UNDERSTAND what's going on!).

Re: Frustrated that I don't UNDERSTAND why my network times out
David Hough wrote:

Quoted text here. Click to load it

I'm not sure what an MTU fragmentation issue is, but, if it
is related to helping to EXPLAIN why I can't connect via the  
web to centos.org, I'll be glad to run *any* diagnostic procedure!

Here's the traceroute -M results:  

# traceroute -M icmp www.centos.org
traceroute to www.centos.org (72.232.194.162), 30 hops max, 60 byte packets
 1  192.168.1.1 (192.168.1.1)  2.836 ms  2.828 ms  2.827 ms
 2  MY_WISP_IP_REDACTED (xxx.xxx.xxx.xxx)  2.835 ms  5.766 ms  5.768 ms
 3  10.50.0.1 (10.50.0.1)  12.510 ms  12.509 ms  16.000 ms
 4  10.25.0.1 (10.25.0.1)  18.880 ms  18.878 ms  18.875 ms
 5  10.20.0.1 (10.20.0.1)  31.081 ms  31.335 ms  34.052 ms
 6  10.0.0.1 (10.0.0.1)  34.050 ms  18.724 ms  28.518 ms
 7  69.36.226.193 (69.36.226.193)  28.488 ms  28.064 ms  28.043 ms
 8  vl2.core1.scl.layer42.net (69.36.225.129)  28.025 ms  47.434 ms  47.413 ms
 9  216.156.84.141.ptr.us.xo.net (216.156.84.141)  47.394 ms  30.086 ms  30.064 ms
10  207.88.14.233.ptr.us.xo.net (207.88.14.233)  80.031 ms  60.416 ms  70.204 ms
11  vb15.rar3.dallas-tx.us.xo.net (207.88.12.45)  70.189 ms  120.949 ms  120.925 ms
12  207.88.14.34.ptr.us.xo.net (207.88.14.34)  120.893 ms  75.048 ms  75.028 ms
13  207.88.185.74.ptr.us.xo.net (207.88.185.74)  75.009 ms  68.640 ms  101.778 ms
14  border1.pc2-bbnet2.dal004.pnap.net (216.52.191.81)  101.762 ms border1.pc1-bbnet1.dal004.pnap.net (216.52.191.19)  77.155 ms  87.903  
ms
15  layered-11.border1.dal004.pnap.net (63.251.44.74)  87.889 ms  120.374 ms  123.342 ms
16  * * *
17  * * *
18  * * *
19  * * *
20  * * *
21  * * *
22  * * *
23  * * *
24  * * *
25  * * *
26  * * *
27  * * *
28  * * *
29  * * *
30  * * *
#

Does any of that help diagnose WHY this one IP address times out on  
port 80 for months on end (and then works just fine for months)?



Re: Frustrated that I don't UNDERSTAND why my network times out
nemesis wrote:

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I'm all for a DIAGNOSTIC approach, since what I'm trying
to figure out is WHY the Internet fails me on just one
web site.

I just tried it from Knoppix and it is the same result
(see below for the details).

I also have tried it from other PC's on the network,  
running Windows XP and Windows 7, and the same thing
occurs.

I also run it via TOR on both Windows & Linux, and it
works fine.

So, its clearly not the PC itself.
It's in the network - but WHERE?

Anyway, here are the Knoppix results:
root@Microknoppix:/# uname -a
Linux Microknoppix 3.6.11-64 #10 SMP PREEMPT Wed Dec 19 23:51:48 CET 2012 x86_64 GNU/Linux

root@Microknoppix:/# ifconfig wlan0 mtu 300

root@Microknoppix:/# traceroute -M icmp centos.org
traceroute to centos.org (72.232.194.162), 30 hops max, 60 byte packets
 1  192.168.1.1 (192.168.1.1)  2.932 ms  2.929 ms  2.928 ms
 2  WISP_IP_REDACTED (xxx.xxx.xxx.xxx)  5.683 ms  5.683 ms  5.680 ms
 3  10.50.0.1 (10.50.0.1)  20.479 ms  20.477 ms  20.474 ms
 4  10.25.0.1 (10.25.0.1)  20.469 ms  30.272 ms  33.014 ms
 5  10.20.0.1 (10.20.0.1)  33.009 ms  36.190 ms  36.187 ms
 6  10.0.0.1 (10.0.0.1)  36.182 ms  16.332 ms  39.405 ms
 7  69.36.226.193 (69.36.226.193)  39.377 ms  20.721 ms  23.093 ms
 8  vl2.core1.scl.layer42.net (69.36.225.129)  23.066 ms  16.977 ms  16.947 ms
 9  216.156.84.141.ptr.us.xo.net (216.156.84.141)  16.917 ms  12.782 ms  18.611 ms
10  207.88.14.233.ptr.us.xo.net (207.88.14.233)  69.341 ms  119.252 ms  119.222 ms
11  vb15.rar3.dallas-tx.us.xo.net (207.88.12.45)  116.010 ms  84.054 ms  84.022 ms
12  207.88.14.34.ptr.us.xo.net (207.88.14.34)  83.978 ms  53.016 ms  52.987 ms
13  207.88.185.74.ptr.us.xo.net (207.88.185.74)  56.341 ms  53.502 ms  59.458 ms
14  border1.pc2-bbnet2.dal004.pnap.net (216.52.191.81)  59.430 ms  58.240 ms border1.pc1-bbnet1.dal004.pnap.net (216.52.191.19)  61.422 ms
15  layered-11.border1.dal004.pnap.net (63.251.44.74)  61.383 ms  54.510 ms  54.494 ms
16  * * * <== centos.org is here  
17  * * *
18  * * *
19  * * *
20  * * *
21  * * *
22  * * *
23  * * *
24  * * *
25  * * *
26  * * *
27  * * *
28  * * *
29  * * *
30  * * *
root@Microknoppix:/#  





Re: Frustrated that I don't UNDERSTAND why my network times out
On Wed, 09 Oct 2013 08:58:25 -0300, nemesis wrote:

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I have the basic Netgear home broadband router, just like most of you do,
and, yes, I have admin as I set it up years ago. Bear in mind that nothing
changes on the router that I know of, when this problem comes and goes
(for months). But, if there was a particular setting on that router that
causes this, I'd love to know what it would be, as mine is set up mostly
at default settings (wpa2-psk encryption).

The one thing I have that most of you do not have is I have another
radio and antenna on my roof since there are no wires or cables going
into my house that contain Internet service (too far from the switch  
for DSL).

For you, that 'thing' on my roof would be the "modem' and for all intents
and purposes, it's the same setup you have, only I get to log into my  
receiver/transmitter and see what its settings are.

Again, I set it up myself, so, I'm admin there also, and, again, nothing
has changed in the two years time that it was set up.  

Meanwhile, the ability to connect by the web to centos.org has come
and gone over time.  

So, while there *could* be a setting in either radio, I wouldn't know
where to look since both are set up in the normal configuration for
a standard WISP setup.

PS: Where is Jeff Liebermann when you need him! :)

Re: Frustrated that I don't UNDERSTAND why my network times out
Quoted text here. Click to load it

You have connection to the web. That is not the problem since you say
you can connect to other places. There is something about centos.org
that is behaving weirdly. Now it could be something on your end, and it
is almost certainly something on their end. They may have decided that
you are a pain in the ass and blackballed you (I have no idea why), or
it might be some sort of technical incompatibility between you and them.  
The only way to clear it up is to talk to them about it. If you cannot
then I cannot see how you are going to figure it out.  
Note you could take your computer with you to some other place which
connects to the web in some other way than your microwave link and see
if that works there.  

Quoted text here. Click to load it

Re: Frustrated that I don't UNDERSTAND why my network times out
On Wed, 09 Oct 2013 19:58:49 +0000, unruh wrote:

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I have long ago written to the Centos.org sysadmins, and they confirm
there is nothing wrong with my IP address or login account.

(The login works fine and no, there's no reason for them to have
blackballed me.)

If it were *that* simple, I wouldn't be asking for networking
advice here ... :)

This is not a simple one.


Re: Frustrated that I don't UNDERSTAND why my network times out
["Followup-To:" header set to comp.os.linux.networking.]
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What do  you mean "the login works fine"? You told us you could not
connect in any way to that machine? Was that wrong?

Quoted text here. Click to load it

It is really hard to give help if information supplied is missing or
wrong.

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Re: Frustrated that I don't UNDERSTAND why my network times out
billy wrote:

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Login?  Are you talking about login here?

https://www.centos.org/user.php

The difference between http and https protocols is the layering of http  
over the SSL/TLS protocol and the other difference is the use of port  
443 instead of 80.

Or perhaps you are talking about logging in to some other server - the  
centos forums are at https centos as well.

The bugs.centos server login is at a different IP 83.149.86.133


--  
Mike Easter

Re: Frustrated that I don't UNDERSTAND why my network times out
Mike Easter wrote:

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All I do, on TOR, is type 'http://www.centos.org ' or "centos.org",  
and it gives me a screen where I can enter in my login and password
and it logs me in. On Firefox, I do the same, when everything is
working.

Then, for months at a time, I can't even connect to www.centos.org
or to 'centos.org' - getting the standard "connection timed out"  
message.  

When I run a traceroute (any type of traceroute), the result is
that the last hop before centos.org is the last hop that returns
anything. The centos.org hop is asterisked out.

There's absolutely nothing wrong with my login (I easily log in
with TOR, and I have an old thread asking THEM what's going on,  
and they don't know either).

So, I 'think' it's the ISP that they use.  

I remember having a similar problem with telephones not being able
to call certain numbers, and, we found out it was a routing thing
at the Ooma headquarters. Nobody on the planet could call these
specific numbers, one of whom was a relative of mine so I knew that
the number existed. Yet, nobody could call the number from VOIP.

Same kind of idea seems to be here. Some router somewhere is very
badly set up.  

The funny thing, is that I'm the only one with the problem.  
Worse yet, there are no debugging tools for when a router is  
dropping packets. That's the saddest part.  

I've been trying to solve this for two years running.  
Or, at least understand how it could possibly happen.


Quoted text here. Click to load it

When I point my browser to http://83.149.86.133 I get the message:
 Forbidden
 You don't have permission to access / on this server.  
 Apache/2.2.3 (CentOS) Server at 83.149.86.133 Port 80

# telnet 83.149.86.133 80
Trying 83.149.86.133...
Connected to 83.149.86.133.
Escape character is '^]'.
HEAD HTTP/1.0
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>400 Bad Request</title>
</head><body>
<h1>Bad Request</h1>
<p>Your browser sent a request that this server could not  
understand.<br />
</p>
<hr>
<address>Apache/2.2.3 (CentOS) Server at mirror.centos.org Port  
80</address>
</body></html>
Connection closed by foreign host.

# traceroute -M icmp 83.149.86.133
# traceroute -M icmp 83.149.86.133
traceroute to 83.149.86.133 (83.149.86.133), 30 hops max, 60 byte  
packets
 1  192.168.1.1 (192.168.1.1)  3.423 ms  3.405 ms  6.261 ms
 2  MY_WISP_ADDRESS (xx.xx.xx.xx)  9.844 ms  9.842 ms  9.839 ms
 3  10.50.0.1 (10.50.0.1)  15.284 ms  139.930 ms  139.937 ms
 4  10.25.0.1 (10.25.0.1)  148.735 ms  148.734 ms  148.729 ms
 5  10.20.0.1 (10.20.0.1)  164.306 ms  169.567 ms  169.564 ms
 6  10.0.0.1 (10.0.0.1)  344.049 ms  70.997 ms  189.575 ms
 7  69.36.226.193 (69.36.226.193)  189.531 ms  34.070 ms  136.902 ms
 8  vl2.core2.scl.layer42.net (69.36.225.130)  139.000 ms  47.370 ms  
133.156 ms
 9  xe3-4.core1.mpt.layer42.net (69.36.239.110)  133.125 ms  35.300 ms  
61.929 ms
10  any2ix.coresite.com (206.223.143.213)  73.838 ms  32.061 ms  94.368  
ms
11  te5-2.msc2.wdc.leaseweb.net (217.20.125.40)  155.304 ms  99.444 ms  
109.215 ms
12  * * *
13  31.31.32.5 (31.31.32.5)  260.392 ms  220.540 ms  229.781 ms
14  ten5-4.sbp-sr2.leaseweb.net (85.17.100.202)  229.737 ms  166.166 ms  
243.165 ms
15  centos.yourname.nl (83.149.86.133)  239.189 ms  176.139 ms  194.943  
ms

So, I have absolutely no problem getting to this site.  
But, why would I have a problem getting to centos.org?

Could it be that anything after 15 hops fails no matter what?
To test, do you know of a site that would be more than 15 hops
away from San Francisco, CA?

Re: Frustrated that I don't UNDERSTAND why my network times out
On Wed, 09 Oct 2013 19:58:49 +0000, unruh wrote:

Quoted text here. Click to load it

It's not the computer because that same computer works fine at  
the library and at Starbucks and at a neighbor's house.

The ONLY thing I can think of that's different is  
a) My IP address (it's static)
b) My home broadband router (standard setup)
c) My WISP radio (standard setup)

But, all of this is local.  

The problem actually seems to occur way down at hop #15,  
which is beyond my control (far beyond my control).

Is there any way to go around that hop #15?


Re: Frustrated that I don't UNDERSTAND why my network times out
Quoted text here. Click to load it

For you? No. Get in touch with them.

Quoted text here. Click to load it

Re: Frustrated that I don't UNDERSTAND why my network times out
unruh wrote:

Quoted text here. Click to load it

I will contact them at the email addresses already posted
and ask them if they're periodically doing something nasty  
to my IP address for months at a time (like putting me on a  
blacklist or something).

I'll report back if/when they respond.


Re: Frustrated that I don't UNDERSTAND why my network times out
Below (sorry for the top post) is the old traceroute from yesterday on
Microknoppix.

Here is the new traceroute from a few seconds ago.
The route is entirely different!
Since *UNDERSTANDING* is what we're after, can you give me
insight into *how* all of a sudden, the route is so very different
(and why it works now)?

Who decides what route my packets will take?

knoppix@Microknoppix:~$ traceroute www.centos.org
traceroute to www.centos.org (85.12.30.227), 30 hops max, 60 byte packets
 1  192.168.1.1 (192.168.1.1)  2.940 ms  2.915 ms  5.895 ms
 2  67-218-118-85.ridgewireless.net (67.218.118.85)  23.983 ms  23.970 ms  23.953 ms
 3  10.50.0.1 (10.50.0.1)  23.935 ms  23.920 ms  23.905 ms
 4  10.25.0.1 (10.25.0.1)  33.716 ms  33.701 ms  33.687 ms
 5  10.20.0.1 (10.20.0.1)  113.640 ms  127.266 ms  127.251 ms
 6  10.0.0.1 (10.0.0.1)  155.135 ms  198.034 ms  198.014 ms
 7  69.36.226.193 (69.36.226.193)  77.534 ms  88.951 ms  88.940 ms
 8  vl2.core2.scl.layer42.net (69.36.225.130)  101.711 ms  101.700 ms  107.203 ms
 9  xe-0-0-0-22.r07.snjsca04.us.bb.gin.ntt.net (140.174.21.101)  111.422 ms  111.419 ms  111.404 ms
10  te0-7-0-32.ccr21.sjc03.atlas.cogentco.com (154.54.11.85)  111.376 ms te0-4-0-32.ccr21.sjc03.atlas.cogentco.com (154.54.10.49)  
111.352 ms te0-7-0-32.ccr21.sjc03.atlas.cogentco.com (154.54.11.85)  111.341 ms
11  be2047.ccr22.sjc01.atlas.cogentco.com (154.54.5.113)  111.324 ms  111.311 ms be2000.ccr21.sjc01.atlas.cogentco.com  
(154.54.6.105)  111.251 ms
12  be2165.ccr22.sfo01.atlas.cogentco.com (154.54.28.65)  111.238 ms be2166.mpd21.sfo01.atlas.cogentco.com (154.54.28.69)  58.660 ms  
be2165.ccr22.sfo01.atlas.cogentco.com (154.54.28.65)  66.012 ms
13  be2132.ccr21.mci01.atlas.cogentco.com (154.54.30.54)  168.366 ms be2135.mpd22.mci01.atlas.cogentco.com (154.54.6.34)  168.350 ms  
be2133.ccr22.mci01.atlas.cogentco.com (154.54.30.66)  165.709 ms
14  be2159.mpd22.ord01.atlas.cogentco.com (154.54.24.82)  168.316 ms  168.300 ms be2158.mpd21.ord01.atlas.cogentco.com  
(154.54.7.130)  168.285 ms
15  be2079.ccr21.yyz02.atlas.cogentco.com (154.54.27.182)  139.555 ms  133.671 ms be2138.ccr22.bos01.atlas.cogentco.com  
(154.54.43.202)  155.781 ms
16  be2090.ccr21.ymq02.atlas.cogentco.com (154.54.30.206)  139.505 ms te0-3-0-1.ccr21.lpl01.atlas.cogentco.com (154.54.31.230)  
208.018 ms te0-4-0-3.ccr22.lpl01.atlas.cogentco.com (154.54.44.190)  208.007 ms
17  te0-5-0-6.ccr21.lpl01.atlas.cogentco.com (154.54.87.65)  211.696 ms be2182.ccr21.ams03.atlas.cogentco.com (154.54.77.245)  
226.780 ms te0-4-0-6.ccr22.lpl01.atlas.cogentco.com (154.54.44.214)  211.705 ms
18  be2185.mpd22.ams03.atlas.cogentco.com (154.54.37.105)  229.203 ms te0-0-0-4.mag21.ams03.atlas.cogentco.com (154.54.76.190)  
310.294 ms be2185.mpd22.ams03.atlas.cogentco.com (154.54.37.105)  310.272 ms
19  10ge-2-3.cr1.ams3.baseip.com (149.6.128.198)  305.393 ms te0-0-0-12.mag21.ams03.atlas.cogentco.com (154.54.76.134)  310.218 ms  
10ge-2-3.cr1.ams3.baseip.com (149.6.128.198)  305.367 ms
20  10ge-2-3.cr1.ams3.baseip.com (149.6.128.198)  305.344 ms  305.321 ms  310.147 ms
21  85.12.30.227 (85.12.30.227)  305.263 ms !X  305.254 ms !X  205.255 ms !X
knoppix@Microknoppix:~$  



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Re: Frustrated that I don't UNDERSTAND why my network times out
On Fri, 11 Oct 2013 14:43:51 +0000, billy wrote:

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    OMG, I'm sorry. I take that back. Unless you are a yoga guru, that was
really bad advice.
Quoted text here. Click to load it

    OK, last bit of advice. You use a wireless ISP. Rainy days, interference
from nearby antennas, antenna positioning and a lot of other stuff can
cause lags and mess up traceroutes.
    Since your problems are not linux or freeware related, keep it on
    alt.internet.wireless
    And check your antenna AND cables for shorts etc.
    HTH

Re: Frustrated that I don't UNDERSTAND why my network times out
On Wed, 09 Oct 2013 12:24:19 +0100, p-0''0-h the cat (ES) wrote:

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I'm all for any diagnostic procedure, so, here's the result from
Windows 7 trace route:

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

C:\Users\billy>traceroute -M icmp www.centos.org
'traceroute' is not recognized as an internal or external command,
operable program or batch file.

C:\Users\billy>tracert www.centos.org

Tracing route to www.centos.org [72.232.194.162] over a maximum of 30 hops:

  1    <1 ms    <1 ms    <1 ms  192.168.1.1
  2     2 ms     1 ms     1 ms  REDACTED_WISP_IP [xxx.xxx.xxx.xxx]
  3     6 ms     2 ms     5 ms  10.50.0.1
  4     5 ms     9 ms     4 ms  10.25.0.1
  5     6 ms    13 ms     5 ms  10.20.0.1
  6    28 ms    18 ms    10 ms  10.0.0.1
  7    10 ms    19 ms    19 ms  69.36.226.193
  8    48 ms    49 ms    26 ms  vl2.core1.scl.layer42.net [69.36.225.129]
  9    15 ms     8 ms     9 ms  216.156.84.141.ptr.us.xo.net [216.156.84.141]
 10    60 ms    60 ms    57 ms  207.88.14.233.ptr.us.xo.net [207.88.14.233]
 11    62 ms    54 ms    60 ms  vb15.rar3.dallas-tx.us.xo.net [207.88.12.45]
 12    69 ms    65 ms    72 ms  207.88.14.34.ptr.us.xo.net [207.88.14.34]
 13    73 ms    53 ms    98 ms  207.88.185.74.ptr.us.xo.net [207.88.185.74]
 14    57 ms    54 ms    54 ms  border1.pc2-bbnet2.dal004.pnap.net [216.52.191.81]
 15    51 ms    75 ms    50 ms  layered-11.border1.dal004.pnap.net [63.251.44.74]
 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.

C:\Users\billy>

At this point, we know:
1. Neither Linux nor Windows can get to http://centos.org
2. TOR has no problem getting to http://centos.org
3. Traceroute shows that the penultimate hop is killing packets

But why?


Re: Frustrated that I don't UNDERSTAND why my network times out
["Followup-To:" header set to comp.os.linux.networking.]
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