[SOLVED] .Net Web app SQL Server Connection String Linux Issue

Issue

I am having issues with a SQL Server connection string that is being used by a .net core App that is deployed on a Linux environment. The .net core app needs to access a sql server on a different server.

My connection string I am using is as follows

"ConnectionStrings" : {
SQLDbContext": "Server=serverabc\\dev_xys;Database=mynewDatabase;Integrated Security = True"
}

It works fine when i run locally on my windows pc

But when its deployed to the Linux box i get the following error

ExtendedSocketException: Name or service not known

System.Net.Dns.GetHostEntryOrAddressesCore(string hostName, bool justAddresses) in Dns.cs, line 323

Exception: Cannot connect to SQL Server Browser. Ensure SQL Server Browser has been started

I have checked the Service account that runs the .Net Service Deployed has access to the database.

Does the connection string need altering?

Solution

This will only work if

1. SQL Server has TCP/IP enabled, and the Browser Service running
2. The Windows firewall allows UDP port 1434 and TCP on whatever port the SQL Server instance is listening on.
3. The client can resolve the hostname

Or you could use the SQL Server Configuration Manager to set the SQL Server instance to listen on a fixed port (1433 is the default), and specify that instead of the instance name in your connection string.

Answered By - David Browne - Microsoft