Cisco 857 not working since ADSL2 upgrade

Answered Question
Jul 6th, 2009


I have a Cisco 857 router. Recently the ISP (BT) have upgraded the ADSL line to ADSL2. Since then, the router is unable to obtain an internet connection. The CD light flashed constantly, and the PPP light never comes on solid.

There have been no changes to the router config. I tried resetting the router to factory defaults, then giving the router a basic config, but I still get the same result.

My ADSL settings:


VPI: 0

VCI: 38

Address: IP Negatiated

Authentication: Chap & Pap

As a test, I swapped the Cisco 857 for a Netgear 834, and the Netgear connected straight away.

Can anyone suggest anything I can try?



Correct Answer by Giuseppe Larosa about 7 years 7 months ago

Hello Nick,

try the following to download an updated firmware


What you want is 3-0-33 FW.

Thanks to Paolo Bevilaqua

Hope to help


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Overall Rating: 5 (1 ratings)
nickc1976 Wed, 07/08/2009 - 07:13


Thanks for your assistance.

IOS version is 2.4

I entered the command "debug pppatm error", and the message "PPP over ATM errors debugging is on" is displayed. But no debug information was shown. Do I need to enter another command to view the output?


Giuseppe Larosa Wed, 07/08/2009 - 11:25

Hello Nick,


sh dsl interface atm0

to be noted:

if the provider DSLAM has been upgraded to ADSL2 it can be a problem because ADSL2+ is backward compatible with ADSL but ADSL2 isn't.

Hope to help


Giuseppe Larosa Fri, 07/10/2009 - 05:37

Hello Nick,

as I've suspected there is incompatibility.

you probaly need a firmware upgrade to achieve a working link.

the easiest way to do this is to load a newer IOS image like 12.4(20)T or later.


if you look in the forum archive you can find the procedure and the link to download newer firmware.

Hope to help


nickc1976 Fri, 07/10/2009 - 05:43

Thanks Giuseppe.

Can I download the latest IOS from this website?


nickc1976 Fri, 07/10/2009 - 06:09

Thanks. I will check it out and let you know how it goes.


thotsaphon Fri, 07/10/2009 - 06:18


Sorry for replying too late. I got a long weekend. As Giuseppe mentioned, you may try to upgrade your ios. However you need to have CCO to access this software. If you've purchased the service you can request user/password from the vendor.


nickc1976 Wed, 07/15/2009 - 06:08


I am struggling to find how to download the software. This is what I have done so far.

"Products and Services"

"Cisco IOS and NX-OS Software"

Cisco IOS Software Releases > Cisco IOS Software Release 12.4T

Support > Download Software

Log in

Download Software > Select a product

Routers > Cisco 800 Series > Cisco 857 Integrated Services Router

Select a release

Latest Release > 12.4.15T9(MD)

Select the link to the file at bottom of page

"To download this software, you must do all of the following:


Due to United States export compliance regulations, you must be registered on to download this software. If you do not have a username and password, please register now. Registration is free. If you have already registered, please log in to proceed."

I am already logged in!

If I select Log in now, I am returned to the previous page!

Giuseppe Larosa Wed, 07/15/2009 - 22:50

Hello Nick,

the CCO account has to be associated to a service contract to be able to download the IOS image.

Contact who has sold you the router.

your account has not enough rights at the moment.

Hope to help


nickc1976 Sat, 07/18/2009 - 05:55


Thanks for the link. I downloaded the file adsl_alc_20190.3-0-33.bin

Next I used the command "copy tftp flash" to update the router. I have attached the results - is this correct?

I will test this at the affected office on Monday and post back the results.


Giuseppe Larosa Sat, 07/18/2009 - 11:10

Hello Nick,

I give you the link to a similar thread in WAN forum

where Andrew explains the file has to be in flash and has to be renamed to the name the router looks for at boot time.

Here are the Andrew's words

You can also independantly load ADSL firmware outside of the IOS image by copying the firmware file to the flash and renaming it to 'adsl_alc_20190.bin'. During the IOS boot the router checks for this file in flash and if it is there loads this instead of the one embedded in the IOS image. The latest firmware for the ADSL modem in the 857/877 is version 4.0.15 and is available here:

Hope to help


nickc1976 Mon, 07/20/2009 - 03:24

Hi Giuseppe,

I renamed the file to adsl_alc_20190.bin, then copied it to the router, and this has now resolved the issue. Thank you for all your help.

Just out of interest, is there a way to remove this file once it has been copied to the flash?



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