I am remotely debugging my application with azure and VS2019 and it works fine until I have to connect to the database.
Then I get the following error. "The underlying provider failed on Open."
On the other hand, if I debug locally everything works correctly.
Do you have to activate any permission in Azure or in the project config so that the database can be accessed remotely?
Right after the connection string I have put the following.
_context.Database.Connection.Open ();
So it returns the following error to me:
"Unable to connect to any of the specified MySQL hosts".
All this locally does not happen to me. Only when trying to debug remotely.
According to your description, we can ensure that the remote debug function of vs2019 is normal. An error is reported in this _context.Database.Connection.Open (); code. Obviously, the program cannot connect to the mysql database server.
Troubleshooting:
First make sure that your mysql database server can be accessed using tools (such as Mysql Workbench).
Using tools to ensure that the database is accessible is to ensure that the firewall of your database server is open (mysql in azure or other server).
Check the connectionstring of mysql in the released program. According to your error message, it is likely that the connection string is used incorrectly.
Related
I am trying to get the Attunity CDC service to work for me on my laptop. I have created the MSXDBCDC database on my SQL Server and am in the process of setting up my first service
Test connection works fine.
I am using a service account that gets assigned to MSXDBCDC when I click OK on the above form
But then I get the following error
I am working from my laptop setting up a dev environment, but the SQL Server is on a server
Can you see anything glaringly obvious wrong with my approach?
I have developed a c# windows application which uses SQL server 2012 database in Visual Studio 2015 which is running well on my pc.
I am to install this application on a number of computers without SQL server installed on it, but when I run the application, its gives me database connection error.
My question is, how can I create the setup file to be able to run the app on those clients pc without installing SQL server on all those computers. Please I need your help.
Thank you.
Am Emmanuel.
Use an Azure database and have the clients connect to that.
Have a look at https://azure.microsoft.com/en-us/services/sql-database/
Alter your application connection string and make sure you keep the connection string secret.
Server=tcp:myserver.database.windows.net,1433;Database=myDataBase;User ID=mylogin#myserver;Password=myPassword;Trusted_Connection=False;Encrypt=True;MultipleActiveResultSets=True;
An important fact is that the clients need to allow communication via port 1433.
If this is not an option create an API application and query the database via that.
If you need a private database per client you can use a database file and connect to the file
https://learn.microsoft.com/en-us/sql/database-engine/configure-windows/sql-server-express-localdb?view=sql-server-ver15
Update based on reply
You can create a pop-up on the application allowing the users to add valid settings and credentials when your appsettings.json is blank or "a test connect" to the database fails.
Using the basic SqlConnection code below, I have discovered that, at my workstation, I am unable to connect to our Sql Server 2017 deployment via ASP.NET C# code in any given type of Windows-based project, such as Winforms (.NET Framework or Core) or Console apps. However, this code will run without incident in any Web-based project, such as Web Forms or MVC, either using .NET Framework or Core.
protected void testConnection()
{
string con = "Server=MySqlServer;database=MyDatabase;Integrated Security=true";
using (SqlConnection cnn = new SqlConnection(con))
{
cnn.Open();
cnn.Close();
}
}
In a web project, this code runs. In a Windows project, I get this error:
System.Data.SqlClient.SqlException: 'A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)'
In investigating this problem, I have tried the following:
Explicitly declaring the domain on which my SQL server is found (eg. MySqlServer.domain.com). No good.
Explicitly declaring the SQL Server port number, according to the example shown on connectionstrings.com (eg. MySqlServer, 1433). We do use the standard port number, for the record. No good.
Changing the protection level of the test method (protected/private/public). No good.
Connecting to the SQL Server in PowerShell. This connection worked.
Pinging in the SQL Server in a command prompt. The server responded in 1ms consistently.
I have asked other users on this network to test this code in a Winforms project on their workstations. No one is able to reproduce my issue.
Consulted my sysadmin. He is so far not able to find any reason why I should be having this issue.
The only difference I have noticed in all of this is that, when I declare the port number, the Inner Exception returned with the error reads "Win32Exception: A non-recoverable error occurred during a database lookup". Otherwise, it simply reads "Access is Denied."
All of this tells me that the issue is obviously something peculiar to my workstation, but I have no idea what, apart from some firewall or other local security setting that the sysadmin neglected to check. Has anyone encountered this problem?
My VS 2019 installation is only one revision out of date as of this writing, 16.8.3 as opposed to 16.8.4. I am able to connect to and run TSQL code on any database I care to via SSMS. We connect using Windows Authentication. According to the results of "select ##version", our version of SQL Server is 2017, 14.0.3356.20 (x64).
Any insight is appreciated.
We fixed it by forcing Named Pipes to be enabled in SQL Server, as opposed to using the default setting.
I'm trying to connect to an SQL database hosted on Azure from a function app I'm building in Visual Studio but I'm getting the following error:
A network-related or instance-specific error occurred while
establishing a connection to SQL Server. The server was not found or
was not accessible. Verify that the instance name is correct and that
SQL Server is configured to allow remote connections. (provider: TCP
Provider, error: 0 - An attempt was made to access a socket in a way
forbidden by its access permissions.)
I can connect from the same PC using SSMS without a problem. I've tried connecting to the database using data connections in server explorer in VS but I'm getting the same error. If I connect to Azure with my account in server explorer it shows me a selection of services including SQL databases but there are none listed underneath although my account does have access to the database.
Are there any hidden gotchas I'm missing or settings within VS? I've also tried adding my client IP in the firewall settings but that didn't make a difference either.
After doing some more testing it turned out to be the client firewall that was blocking VS and VS Code from connecting to Azure SQL. It seems there was already an exception for SSMS.
The error message states "Verify that the instance name is correct"
It could be that the SSMS is automatically creating a fully qualified name once you say that it is an azure database.
If you use the short name from Visual Studio, then you cannot connect to the SQL server.
For example "myserver.database.windows.net" versus "myserver".
I'm trying to setup a startup template to play around with boilerplate and see what it could potentially offer and I'm running into issues setting up my local database.
I've tried the core startup template download as well as MVC 5 and they've both given me the same issue so far. I'll open up the solution in VS 2017, clean the solution, rebuild, enter Package Manager Console and execute Update-Database on the EntityFramework project and I get this error on both projects,
ClientConnectionId:00000000-0000-0000-0000-000000000000
Error Number:2,State:0,Class:20
A network-related or instance-specific error occurred while establishing
a connection to SQL Server. The server was not found or was not accessible.
Verify that the instance name is correct and that SQL Server is configured
to allow remote connections. (provider: Named Pipes Provider, error: 40 -
Could not open a connection to SQL Server)
I'm having a hard time understanding what this might be indicating. I'm pretty sure I've been able to use my local db in other projects recently.
You need to set up an empty database and provide a valid connection string in appsettings.json.
You can use Microsoft's SQL Server.