FB 4.0 authentication error -with .NET 8 connection wie nuget connection string

[J. P]

we try to connect to a firebird 4.0 via Nuget and connection string, but we always get

back from the Firebird 4.0 (firebird.log)

Authentication error
No matching plugins on server

we installed .net 8 on the firebird server and tried several settings 

(AuthServer = Srp256, Srp, Legacy_Auth)

in the firebird.config, but always the same error

What are we missing? 

What else can we try?

[Mark Rotteveel]

Which version of the Firebird ADO.NET provider are you using?

It sounds like you're using a very old one which doesn't support Srp at
all. Although then I'd expect it to be able to use Legacy_Auth, which
suggests you didn't restart after changing AuthServer, or you still have
it commented out.

Mark
--
Mark Rotteveel

[J. P]

Thx for your answer!!

firebird.config:

AuthServer =  Legacy_Auth

AuthClient = Srp256, Srp, Legacy_Auth           #Non Windows clients

only microsoft .NET SDK 8.0.410 (version 8.4.1025.26616) is installed on server, where firebird is installed.

Do we need additional installation on the server for firebird?

thx for reply!

Jürgen

[Mark Rotteveel]

On 10/06/2025 16:10, J. P wrote:
> Thx for your answer!!
>
> firebird.config:
> AuthServer =  Legacy_Auth
> AuthClient = Srp256, Srp, Legacy_Auth           #Non Windows clients
>
> only microsoft .NET SDK 8.0.410 (version 8.4.1025.26616) is installed on
> server, where firebird is installed.
> Do we need additional installation on the server for firebird?

I asked about the version of the Firebird ADO.NET provider (a.k.a.
FirebirdSql.Data.FirebirdClient), the driver your .NET application is
probably using.

In any case, with the setting AuthServer = Legacy_Auth, recent versions
of the Firebird ADO.NET provider will *not* work, because that driver
only supports the Srp family of authentication plugins when connecting
to Firebird 3.0 or higher.

So, change the setting to

AuthServer = Srp256, Srp, Legacy_Auth

and restart Firebird (you also need to ensure that the user in question
exists for the Srp user manager).

Also, make sure you really need to use Legacy_Auth, otherwise it's
better to remove it from the AuthServer list.

Mark
--
Mark Rotteveel