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Invalid password. Server to Client challange do not match

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By bhatiasidharth.89 , 12 August, 2021
Forums
DLMSDirector

I created a sample meter with an Arduino Mega using Gurux's sample Arduino code then tried to connect to it using the DLMS director. I If I connect with the authentication set to High and password as 'Gurux' (as described in Gurux's youtube video about the DLMS director) I get an error message: 'Invalid password. Server to Client challange do not match.' I am able to connect to the meter when I set the authentication to none. Request you to please help in this regard.

Thanks

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Kurumi

4 years 10 months ago

Hi,

Hi,

What version you are using from Arduino IDE?
BR,
Mikko

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Kurumi

4 years 10 months ago

Hi,

Hi,

There is a new version where Low and High-level passwords are print to trace on startup.
I hope it will help you.

BR,
Mikko

bhatiasidharth.89

4 years 10 months ago

Hi Mikko,

Hi Mikko,

Thanks for adding the prints for the Low and High-level passwords to trace on startup. I tried but still the same issue. The password for hls is printed as Gurux but I am not able to connect to the meter using the High authentication in DLMS director. Here are the logs that I get from the meter when I try to connect in High authentication mode:
Meter started...:Communication speed 9600..:Test mode Is ON...:LLS passwordGurux..:HLS passwordGurux..:EEPROM size 4096..:Server started...:svr_preAction: 40 0.0.25.9.0.255..:sendPush40 0.0.25.9.0.255..:svr_preRead: 1 0.0.42.0.0.255..:svr_postRead: 1 0.0.42.0.0.255..:svr_preRead: 40 0.0.25.9.0.255..:svr_postRead: 40 0.0.25.9.0.255..:svr_isTarget...:Connecting using High authentication...:svr_validateAuthentication..:findObject15 0.0.40.0.0.255..:findObject15 0.0.40.0.0.255..:svr_preAction: 15 0.0.40.0.3.255..:svr_postAction: 15 0.0.40.0.3.255..:svr_invalidConnection.

I should also add that I am able to connect to the meter using the Low authentication in DLMS director. In this case too the password printed at startup for lls is Gurux and this password does work for Low authentication connection.

Profile picture for user Kurumi

Kurumi

4 years 10 months ago

Hi,

Hi,

I took the latest version from GitHub and it worked without problems.
Are you using settings like in the pic below?

BR,
Mikko

Image

bhatiasidharth.89

4 years 10 months ago

Hi Mikko,

Hi Mikko,

Sorry I missed your first question. I am using Arduino IDE version 1.8.13.

Thanks

Profile picture for user Kurumi

Kurumi

4 years 10 months ago

Hi,

Hi,

Have you made any changes to the source code except gxignore.h?
Reject all the changes from the other files.

Uncomment only those from gxignore.h
#define DLMS_IGNORE_CLIENT
#define DLMS_IGNORE_MALLOC

BR,
Mikko

bhatiasidharth.89

4 years 10 months ago

Hi Mikko,

Hi Mikko,

I downloaded the latest version from github again and the latest Arduino IDE 1.8.15 and it worked. Thanks.
I have a suggestion though. The arduino code does not compile straightaway. But the only change I needed to make it work is to declare two function prototypes at the top of server.ino file as in the attached image. If possible please add this to the git repo as It would make it easier for people to start with the library. Otherwise the compiler shows a lot of unrelated errors.

Thanks

Image
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