why am I getting an SSPI context error when connecting to a SQL server from an entra joined jump host?

Question

Hi all, I am working with a vendor and they need to connect to our SQL VM through a Jump Host that is using Entra ID. We are getting the error "The target principle name is incorrect. Cannot generate SSPI context". This only happens from the jump host. It does not happen when we connect from any of the other VM's in the same subnet, resource group etc. Is it because Entra does not pass credentials as expected? Are there any workarounds? Thank you!

Answer 1

Hello Dreamwarrior76

The “The target principle name is incorrect. Cannot generate SSPI context” error occurs when a user tries to connect to a SQL Server instance using a domain account and receives the error message.
This error message indicates that the SQL Server service cannot locate a domain controller(Entra ID) to authenticate the user’s account.

There are multiple reasons for this error. Here are couple reasons and solutions to fix an error:

• Check the SQL Server configuration settings. You should verify that the SQL Server is configured to use Windows Authentication and that the SQL Server service account has the appropriate permissions to access the domain controller.
• Please make sure firewall rules for the database are configured to "Allow access to Azure services" as you can see on below image, and you would need to set up a firewall rule to allow the public IP address used to make a connection. Also make sure you choose Database authentication mode
• Verify SQL Server SPNs using SQLCheck and Setspn tools. https://learn.microsoft.com/en-us/troubleshoot/sql/database-engine/connect/cannot-generate-sspi-context-error#step-3-verify-sql-server-spns-using-sqlcheck-and-setspn-tools https://learn.microsoft.com/en-us/answers/questions/1368194/microsoft-sql-the-target-principal-name-is-incorre
  https://learn.microsoft.com/en-us/troubleshoot/sql/database-engine/connect/cannot-generate-sspi-context-error

Answer 2

So they log on to the VM with Entra ID, and then they try log on to SQL Server with Windows Auth?

I cannot claim a whole lot of expertise in this area, but I would only expect this to work if you have SQL 2022, and you have enabled the instance for Entra ID authentication. And the vendor would have to select Microsoft Entra Integrated.

For Windows Authentication to work, there has to be a Windows user somewhere.

Answer 3

Hello @dreamwa The error “The target principal name is incorrect. "Cannot generate SSPI context” typically occurs when you use Windows authentication to connect to a SQL Server instance remotely.

This error means that SSPI (Security Support Provider Interface) tries but can’t use Kerberos authentication to delegate client credentials through TCP/IP or Named Pipes to SQL Server. In most cases, a misconfigured Service Principal Name (SPN) causes this error.

A Service Principal Names (SPN) is a unique identifier of a service instance. SPNs are used by Kerberos authentication to associate a service instance with a service logon account. For example, a typical SPN for a server that is running an instance of SQL Server is as follows: MSSQLSvc/SQLSERVER1.northamerica.corp.mycompany.com:1433.

If the SPN is not configured correctly, or if the client system is not able to reach the Domain Controller, it can result in the error message you’re seeing. One possible solution is to delete the registered SPN for your SQL Service under the incorrect account, and then register the SPN under the correct service account.

I hope this answers your question, and the links provided helps you.