[SLUG] the curious case of the inaccessible websites

[david]

I have a "business ethernet" internet connection from a TPG reseller.

Suddenly some external websites or partial websites are inaccessible
from local clients. I haven't yet figured out a pattern, but it looks
like javascript or some such is holding up the webpage download. The
browser is waiting for a script or css or something not immediately
obvious. I get the same problem with different browsers.

Some sites work perfectly - eg Westpac. The ABC site works, but after
apparently loading it then constantly waits for something but I can't
tell what. Some google responses work and some don't.

For example, http://www.trivago.com.au waits indefinitely for
jse.trivago.com and never loads, although I can telnet to port 80. BTW,
lynx works fine - which makes me more suspicious that it's CSS or some such.

I rang the help desk late on Friday. They suggested DNS (??), but I
don't think that's it because I tried using an external DNS server and
in any case there doesn't seem to be any resolution problem. On their
suggestion I've rebooted both the Cisco router and NTU with no change.
Does anybody have any thoughts?

David
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[Michael McAllister]

It smells like MTU. Run some pings and play around with the packet size to find out when it gets fragmented.


From: david
Sent: Monday 8 June 3:25 pm
Subject: [SLUG] the curious case of the inaccessible websites
To: ***@slug.org.au

I have a "business ethernet" internet connection from a TPG reseller. Suddenly some external websites or partial websites are inaccessible from local clients. I haven't yet figured out a pattern, but it looks like javascript or some such is holding up the webpage download. The browser is waiting for a script or css or something not immediately obvious. I get the same problem with different browsers. Some sites work perfectly - eg Westpac. The ABC site works, but after apparently loading it then constantly waits for something but I can't tell what. Some google responses work and some don't. For example, http://www.trivago.com.au waits indefinitely for jse.trivago.com and never loads, although I can telnet to port 80. BTW, lynx works fine - which makes me more suspicious that it's CSS or some such. I rang the help desk late on Friday. They suggested DNS (??), but I don't think that's it because I tried using an external DNS server and in any case there doesn't seem to be any resolution
problem. On their suggestion I've rebooted both the Cisco router and NTU with no change. Does anybody have any thoughts? David -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
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[DaZZa]

What browser?

Recently, Chrome (and possibly Firefox) decided that all java pugins (and
others like Silverlight) were "unsecured", and the simply stopped allowing
the plugins to work.

Broke countless business-related Web sites - I had a storm of them, all
being blamed on "the firewall", or "the network".

I can't find the reference articles I dug up at the time as I'm mobile,
but try a different browser and see if that helps.

DaZZa
On 08/06/2015 3:24 PM, "david" <***@kenpro.com.au> wrote:

> I have a "business ethernet" internet connection from a TPG reseller.
>
> Suddenly some external websites or partial websites are inaccessible from
> local clients. I haven't yet figured out a pattern, but it looks like
> javascript or some such is holding up the webpage download. The browser is
> waiting for a script or css or something not immediately obvious. I get the
> same problem with different browsers.
>
> Some sites work perfectly - eg Westpac. The ABC site works, but after
> apparently loading it then constantly waits for something but I can't tell
> what. Some google responses work and some don't.
>
> For example, http://www.trivago.com.au waits indefinitely for
> jse.trivago.com and never loads, although I can telnet to port 80. BTW,
> lynx works fine - which makes me more suspicious that it's CSS or some such.
>
> I rang the help desk late on Friday. They suggested DNS (??), but I don't
> think that's it because I tried using an external DNS server and in any
> case there doesn't seem to be any resolution problem. On their suggestion
> I've rebooted both the Cisco router and NTU with no change. Does anybody
> have any thoughts?
>
> David
> --
> SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
>
--
SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html

[Amos Shapira]

You probably refer to the drop of support for NPAPI (e.g. article in
http://venturebeat.com/2014/11/24/google-chrome-will-block-all-netscape-plugin-api-plugins-in-january-drop-support-completely-in-september/
about Chrome but Firefox is following cloesely behind).

There are temporary work-around provided by Google to keep letting some
plugins to be enabled by some sites, but they are all expected to be gone
by the end of 2015 so should better find alternatives soon.

As for the original question - I doubt that it's a plugin issue. It sounds
more like some of the dependent resources on these pages are being blocked
or otherwise (temporarily?) unavailable. What does the JavaScript console
show? Do you have some corporate proxy which could be misbehaving?

Just for shits and giggles, I visited www.trivago.com.au and had no problem
accessing it, even on my flaky home ADSL2+ line.

--Amos

On 8 June 2015 at 17:13, DaZZa <***@gmail.com> wrote:

> What browser?
>
> Recently, Chrome (and possibly Firefox) decided that all java pugins (and
> others like Silverlight) were "unsecured", and the simply stopped allowing
> the plugins to work.
>
> Broke countless business-related Web sites - I had a storm of them, all
> being blamed on "the firewall", or "the network".
>
> I can't find the reference articles I dug up at the time as I'm mobile,
> but try a different browser and see if that helps.
>
> DaZZa
> On 08/06/2015 3:24 PM, "david" <***@kenpro.com.au> wrote:
>
> > I have a "business ethernet" internet connection from a TPG reseller.
> >
> > Suddenly some external websites or partial websites are inaccessible from
> > local clients. I haven't yet figured out a pattern, but it looks like
> > javascript or some such is holding up the webpage download. The browser
> is
> > waiting for a script or css or something not immediately obvious. I get
> the
> > same problem with different browsers.
> >
> > Some sites work perfectly - eg Westpac. The ABC site works, but after
> > apparently loading it then constantly waits for something but I can't
> tell
> > what. Some google responses work and some don't.
> >
> > For example, http://www.trivago.com.au waits indefinitely for
> > jse.trivago.com and never loads, although I can telnet to port 80. BTW,
> > lynx works fine - which makes me more suspicious that it's CSS or some
> such.
> >
> > I rang the help desk late on Friday. They suggested DNS (??), but I don't
> > think that's it because I tried using an external DNS server and in any
> > case there doesn't seem to be any resolution problem. On their suggestion
> > I've rebooted both the Cisco router and NTU with no change. Does anybody
> > have any thoughts?
> >
> > David
> > --
> > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
> >
> --
> SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
>



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[David]

It seems that "an upstream supplier" has made changes that specifically
require an MTU of 1492. Problem solved.

Only some sites were affected, which made it confusing. I can't imagine
why anyone would do this and not tell anybody. My reseller couldn't tell
me who the "upstream supplier" is, except that it isn't TPG.

Go figure.

On 08/06/15 18:41, Amos Shapira wrote:
> You probably refer to the drop of support for NPAPI (e.g. article in
> http://venturebeat.com/2014/11/24/google-chrome-will-block-all-netscape-plugin-api-plugins-in-january-drop-support-completely-in-september/
> about Chrome but Firefox is following cloesely behind).
>
> There are temporary work-around provided by Google to keep letting
> some plugins to be enabled by some sites, but they are all expected to
> be gone by the end of 2015 so should better find alternatives soon.
>
> As for the original question - I doubt that it's a plugin issue. It
> sounds more like some of the dependent resources on these pages are
> being blocked or otherwise (temporarily?) unavailable. What does the
> JavaScript console show? Do you have some corporate proxy which could
> be misbehaving?
>
> Just for shits and giggles, I visited www.trivago.com.au
> <http://www.trivago.com.au> and had no problem accessing it, even on
> my flaky home ADSL2+ line.
> --Amos
>
> On 8 June 2015 at 17:13, DaZZa <***@gmail.com
> <mailto:***@gmail.com>> wrote:
>
> What browser?
>
> Recently, Chrome (and possibly Firefox) decided that all java
> pugins (and
> others like Silverlight) were "unsecured", and the simply stopped
> allowing
> the plugins to work.
>
> Broke countless business-related Web sites - I had a storm of
> them, all
> being blamed on "the firewall", or "the network".
>
> I can't find the reference articles I dug up at the time as I'm
> mobile,
> but try a different browser and see if that helps.
>
> DaZZa
> On 08/06/2015 3:24 PM, "david" <***@kenpro.com.au
> <mailto:***@kenpro.com.au>> wrote:
>
> > I have a "business ethernet" internet connection from a TPG
> reseller.
> >
> > Suddenly some external websites or partial websites are
> inaccessible from
> > local clients. I haven't yet figured out a pattern, but it looks
> like
> > javascript or some such is holding up the webpage download. The
> browser is
> > waiting for a script or css or something not immediately
> obvious. I get the
> > same problem with different browsers.
> >
> > Some sites work perfectly - eg Westpac. The ABC site works, but
> after
> > apparently loading it then constantly waits for something but I
> can't tell
> > what. Some google responses work and some don't.
> >
> > For example, http://www.trivago.com.au waits indefinitely for
> > jse.trivago.com <http://jse.trivago.com> and never loads,
> although I can telnet to port 80. BTW,
> > lynx works fine - which makes me more suspicious that it's CSS
> or some such.
> >
> > I rang the help desk late on Friday. They suggested DNS (??),
> but I don't
> > think that's it because I tried using an external DNS server and
> in any
> > case there doesn't seem to be any resolution problem. On their
> suggestion
> > I've rebooted both the Cisco router and NTU with no change. Does
> anybody
> > have any thoughts?
> >
> > David
> > --
> > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
> >
> --
> SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
>
>
>
>
> --
> <http://au.linkedin.com/in/gliderflyer>

--
David McQuire
0418 310312

--
SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html

[Amos Shapira]

"tcptraceroute" (or "traceroute -T" in some versions) could possibly expose
the culprit, it's a very useful tool to have in your toolbox for such
situations.

On 9 June 2015 at 11:34, David <***@kenpro.com.au> wrote:

> It seems that "an upstream supplier" has made changes that specifically
> require an MTU of 1492. Problem solved.
>
> Only some sites were affected, which made it confusing. I can't imagine
> why anyone would do this and not tell anybody. My reseller couldn't tell me
> who the "upstream supplier" is, except that it isn't TPG.
>
> Go figure.
>
> On 08/06/15 18:41, Amos Shapira wrote:
>
> You probably refer to the drop of support for NPAPI (e.g. article in
> http://venturebeat.com/2014/11/24/google-chrome-will-block-all-netscape-plugin-api-plugins-in-january-drop-support-completely-in-september/
> about Chrome but Firefox is following cloesely behind).
>
> There are temporary work-around provided by Google to keep letting some
> plugins to be enabled by some sites, but they are all expected to be gone
> by the end of 2015 so should better find alternatives soon.
>
> As for the original question - I doubt that it's a plugin issue. It
> sounds more like some of the dependent resources on these pages are being
> blocked or otherwise (temporarily?) unavailable. What does the JavaScript
> console show? Do you have some corporate proxy which could be misbehaving?
>
> Just for shits and giggles, I visited www.trivago.com.au and had no
> problem accessing it, even on my flaky home ADSL2+ line.
>
> --Amos
>
> On 8 June 2015 at 17:13, DaZZa <***@gmail.com> wrote:
>
>> What browser?
>>
>> Recently, Chrome (and possibly Firefox) decided that all java pugins (and
>> others like Silverlight) were "unsecured", and the simply stopped allowing
>> the plugins to work.
>>
>> Broke countless business-related Web sites - I had a storm of them, all
>> being blamed on "the firewall", or "the network".
>>
>> I can't find the reference articles I dug up at the time as I'm mobile,
>> but try a different browser and see if that helps.
>>
>> DaZZa
>> On 08/06/2015 3:24 PM, "david" <***@kenpro.com.au> wrote:
>>
>> > I have a "business ethernet" internet connection from a TPG reseller.
>> >
>> > Suddenly some external websites or partial websites are inaccessible
>> from
>> > local clients. I haven't yet figured out a pattern, but it looks like
>> > javascript or some such is holding up the webpage download. The browser
>> is
>> > waiting for a script or css or something not immediately obvious. I get
>> the
>> > same problem with different browsers.
>> >
>> > Some sites work perfectly - eg Westpac. The ABC site works, but after
>> > apparently loading it then constantly waits for something but I can't
>> tell
>> > what. Some google responses work and some don't.
>> >
>> > For example, http://www.trivago.com.au waits indefinitely for
>> > jse.trivago.com and never loads, although I can telnet to port 80. BTW,
>> > lynx works fine - which makes me more suspicious that it's CSS or some
>> such.
>> >
>> > I rang the help desk late on Friday. They suggested DNS (??), but I
>> don't
>> > think that's it because I tried using an external DNS server and in any
>> > case there doesn't seem to be any resolution problem. On their
>> suggestion
>> > I've rebooted both the Cisco router and NTU with no change. Does anybody
>> > have any thoughts?
>> >
>> > David
>> > --
>> > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
>> > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
>> >
>> --
>> SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
>> Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
>>
>
>
>
> --
> <http://au.linkedin.com/in/gliderflyer>
>
>
> --
> David McQuire0418 310312
>
>


--
<http://au.linkedin.com/in/gliderflyer>
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Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html

[Michael McAllister]

Glad to hear you got your MTU issue fixed :-)


Sent by Outlook<http://taps.io/outlookmobile> for Android



On Mon, Jun 8, 2015 at 10:02 PM -0700, "David" <***@kenpro.com.au<mailto:***@kenpro.com.au>> wrote:

It seems that "an upstream supplier" has made changes that specifically
require an MTU of 1492. Problem solved.

Only some sites were affected, which made it confusing. I can't imagine
why anyone would do this and not tell anybody. My reseller couldn't tell
me who the "upstream supplier" is, except that it isn't TPG.

Go figure.

On 08/06/15 18:41, Amos Shapira wrote:
> You probably refer to the drop of support for NPAPI (e.g. article in
> http://venturebeat.com/2014/11/24/google-chrome-will-block-all-netscape-plugin-api-plugins-in-january-drop-support-completely-in-september/
> about Chrome but Firefox is following cloesely behind).
>
> There are temporary work-around provided by Google to keep letting
> some plugins to be enabled by some sites, but they are all expected to
> be gone by the end of 2015 so should better find alternatives soon.
>
> As for the original question - I doubt that it's a plugin issue. It
> sounds more like some of the dependent resources on these pages are
> being blocked or otherwise (temporarily?) unavailable. What does the
> JavaScript console show? Do you have some corporate proxy which could
> be misbehaving?
>
> Just for shits and giggles, I visited www.trivago.com.au<http://www.trivago.com.au>
> <http://www.trivago.com.au> and had no problem accessing it, even on
> my flaky home ADSL2+ line.
> --Amos
>
> On 8 June 2015 at 17:13, DaZZa <***@gmail.com
> <mailto:***@gmail.com>> wrote:
>
> What browser?
>
> Recently, Chrome (and possibly Firefox) decided that all java
> pugins (and
> others like Silverlight) were "unsecured", and the simply stopped
> allowing
> the plugins to work.
>
> Broke countless business-related Web sites - I had a storm of
> them, all
> being blamed on "the firewall", or "the network".
>
> I can't find the reference articles I dug up at the time as I'm
> mobile,
> but try a different browser and see if that helps.
>
> DaZZa
> On 08/06/2015 3:24 PM, "david" <***@kenpro.com.au
> <mailto:***@kenpro.com.au>> wrote:
>
> > I have a "business ethernet" internet connection from a TPG
> reseller.
> >
> > Suddenly some external websites or partial websites are
> inaccessible from
> > local clients. I haven't yet figured out a pattern, but it looks
> like
> > javascript or some such is holding up the webpage download. The
> browser is
> > waiting for a script or css or something not immediately
> obvious. I get the
> > same problem with different browsers.
> >
> > Some sites work perfectly - eg Westpac. The ABC site works, but
> after
> > apparently loading it then constantly waits for something but I
> can't tell
> > what. Some google responses work and some don't.
> >
> > For example, http://www.trivago.com.au waits indefinitely for
> > jse.trivago.com <http://jse.trivago.com> and never loads,
> although I can telnet to port 80. BTW,
> > lynx works fine - which makes me more suspicious that it's CSS
> or some such.
> >
> > I rang the help desk late on Friday. They suggested DNS (??),
> but I don't
> > think that's it because I tried using an external DNS server and
> in any
> > case there doesn't seem to be any resolution problem. On their
> suggestion
> > I've rebooted both the Cisco router and NTU with no change. Does
> anybody
> > have any thoughts?
> >
> > David
> > --
> > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
> >
> --
> SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
> Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
>
>
>
>
> --
> <http://au.linkedin.com/in/gliderflyer>

--
David McQuire
0418 310312

--
SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/
Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
--
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Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html

[James Gray]

> On 8 Jun 2015, at 5:13 pm, DaZZa <***@gmail.com> wrote:
>
> What browser?
>
> Recently, Chrome (and possibly Firefox) decided that all java pugins (and
> others like Silverlight) were "unsecured", and the simply stopped allowing
> the plugins to work.
>
> Broke countless business-related Web sites - I had a storm of them, all
> being blamed on "the firewall", or "the network".
>
> I can't find the reference articles I dug up at the time as I'm mobile,
> but try a different browser and see if that helps.
>
> DaZZa

Amos beat me to the chase, and I think he’s on the money. Chrome is phasing our NPAPI plugins (Java, Flash and a bunch of others) and I understand Firefox is going the same way too, albeit on a slightly different schedule:
http://en.wikipedia.org/wiki/NPAPI

I got bitten on the arse with Java in Chrome (thanks Oracle, IBM and other dinosaurs
you suck!) so I still have to fire up Firefox until they too drop support, then I’m royally screwed. We have a very finite mix of browsers and Java versions that work with our “enterprise” data warehouse - Java 6u45 and that’s it. Yep, one version works, all others fail in subtle and/or spectacular ways at different points. Yay.

Good luck.

--
James

[James Gray]

> On 8 Jun 2015, at 2:10 pm, david <***@kenpro.com.au> wrote:
>
> I have a "business ethernet" internet connection from a TPG reseller.
>
> Suddenly some external websites or partial websites are inaccessible from local clients. I haven't yet figured out a pattern, but it looks like javascript or some such is holding up the webpage download. The browser is waiting for a script or css or something not immediately obvious. I get the same problem with different browsers.

—>8— snipped

> For example, http://www.trivago.com.au waits indefinitely for jse.trivago.com and never loads, although I can telnet to port 80. BTW, lynx works fine - which makes me more suspicious that it's CSS or some such.

FWIW, you can test the jse.trivago.com request by manually requesting (from Safari on OS X): http://jse.trivago.com/osp/v9_05_4ae/pricesearch/js/common.es5.ltr.ec.js

It’s just a big JS library for hunting prices down. I had some fun messing round with the local copy, so some prices for $1000+/night hotels came up as “FREE!”
would be fun getting them to price match that :)

—>8— snipped again


As for the weird connectivity, I know TPG for a long time ran transparent proxies without really making it widely known. I’ve seen similar behaviour to that which you describe when my local Squid cache get’s it’s panties in a bunch. “squid -k restart” usually does the trick. However, before rattling TPG’s cage, maybe try flushing the browser cache and see if the problems persist.

Good luck.

--
James

[Amos Shapira]

On 8 June 2015 at 18:59, James Gray <***@gray.net.au> wrote:

> As for the weird connectivity, I know TPG for a long time ran transparent
> proxies without really making it widely known. I’ve seen similar behaviour
> to that which you describe when my local Squid cache get’s it’s panties in
> a bunch. “squid -k restart” usually does the trick. However, before
> rattling TPG’s cage, maybe try flushing the browser cache and see if the
> problems persist.
>

Or try using a VPN to escape the TPG cage and see if it helps?
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