Kitz Forum

Broadband Related => Broadband Hardware => Topic started by: hake on January 20, 2009, 09:33:59 AM

Title: Calling all BT Voyager 2100 users
Post by: hake on January 20, 2009, 09:33:59 AM
Are you able to browse the www.adobe.com web site through your BT Voyager 2100?

None of my pool of three BT Voyager 2100 routers will permit that (one is deployed at my wife's sisters' house 40 miles away from me).  When I use a Solwise SAR110 or SmartAX MT 882, the Adobe web site can be browsed.  I use Internet Explorer, Firefox, Opera and Google Chrome.  It happens on both my Windows XP systems and with Windows 98SE.

The browser sends the request to the server but the server reply just doesn't get through.   The web browser client screen remains blank.  I can ping www.adobe.com and get the proper response.

The Voyagers are using the latest firmware ( 2.18.01.17i_a023g1.d15g ) but the problem also happens with older firmware.

I rarely visit the Adobe web site except to download updates for the Flash player so it is hardly a real problem.

I have experienced no such problems with browsing any other web site.

Acrobat.com is also unable to function when communicating through the Voyager.

I am mystified.   :'(
Title: Re: Calling all BT Voyager 2100 users
Post by: kitz on January 20, 2009, 01:07:10 PM
Hi hake

I dont (cant) use the 2100 anymore since its not adsl2+, but you not being able to reach a site reminds me of a problem that I had with my 2100 in that there were a couple of sites that I had difficulty reaching.  This problem bugged me for months and months until I eventually fixed it.  One of the sites I couldnt get to was http://www.arrse.co.uk/

I actually found the solution was something to do with MTU and the way the 2100 handled the MSS.  I'm going from memory now because its a bug in the way the firmware dealt with the difference between MTU and the MSS.

Theres 2 places in the 2100 where you have to set MTU and if you dont set them both it has problems.. and it also seems to have problems if they are not set at 1500.  Unfortunately now because I cant access mine I cant recall where both settings are that need to be changed.. but theres defintely 2 places in the web interface where it needs to be done.
Title: Re: Calling all BT Voyager 2100 users
Post by: hake on January 20, 2009, 01:44:19 PM
Thank you Kitz :flower: .  I had set the MTU to 1430.  Setting it to 1500 in both places has solved the problem. :)
Title: Re: Calling all BT Voyager 2100 users
Post by: kitz on January 20, 2009, 02:16:32 PM
yw - glad it solved the problem :)

There was some official explanation what the problem was but its so long ago now that I cant recall :/
Title: Re: Calling all BT Voyager 2100 users
Post by: bobpullen on January 20, 2009, 03:07:10 PM
I've a 2110 and 2091 that both work fine with the MTU configured to 1430. I have set the adapters on my machines to use this value too mind you.
Title: Re: Calling all BT Voyager 2100 users
Post by: kitz on January 20, 2009, 06:09:14 PM
Hiya Bob thanks for the input.

This one plagued me for ages and I did have 1430 set on the local machines. I also tried various other MTUs but it still played silly beggars.  Tomo was involved in this at some point too and like the OP everything worked fine with other routers - just the 2100. 

Going back to 2006 when I was beta testing the new multicast firmware Ian pollock first mentioned this problem and that it only seemed to be occuring on the PN platform - but I wasnt experiencing it then and it only came about later.  Voyager wrote it off as a plusnet specific problem.  It was only later when I got affected and I also started seeing it crop up with some other ISPs too that I decided to investigate further. 

The full details and Tomo's explanation are some where in the PUG forums and I mentioned that if any of your customers are using the 2100 and are having problems with odd pages not displaying properly to try 1500 MTU in both settings.  This has also helped some of your other customers displaying the same symptoms using the 2100.

Another way which it may materialise is that if the ellacoyas/centrals are busy, then speeds will also take an artificial dive as it works fine on RIN.


[edited to add]

FYI you may also be interested in this thread (http://community.plus.net/forum/index.php/topic,62056.0.html) where someone else with a 2100 said they couldnt reach the Adobe site unless MTU was set at 1500 on the router.
Title: Re: Calling all BT Voyager 2100 users
Post by: spudnik on February 09, 2009, 09:19:01 AM
 I had this problem for several weeks. It was first noticed when trying to login into www.reguk.co.uk login site. The captcha image never appeared.
Then when trying to access adobe.com site, all I got was timed out. This occured on three computers networked together. Therefore assumed it must be the router.
When checking the default settings on voyager 2100 I noticed that the MTU for the internet was set at 1500 and the MTU for local network was 1400.
I changed the local network to 1500 to match. Once the settings were saved and router rebooted, all pages / sites could be accessed. All still working fine.
Title: Re: Calling all BT Voyager 2100 users
Post by: kitz on February 09, 2009, 12:57:27 PM
Quote
MTU for local network was 1400

Thats the one - I believe its set as 1400 by default on some firmware versions.

Quote
the MTU for the internet was set at 1500

..  and because that figure is more easily accessible most people looking, think that the router MTU must be set correctly.

Quote
I changed the local network to 1500 to match. Once the settings were saved and router rebooted, all pages / sites could be accessed. All still working fine.

Glad you sorted it and thanks for letting us know  :)

Title: Re: Calling all BT Voyager 2100 users
Post by: audiolab on February 09, 2009, 06:51:55 PM
i had a 2100 a long time ago ,i used it all the time palying xbox live,so much one of the led's melted