Unable to start Test Data on Demand (TDoD) Service. Error: Exception: A connection was successfully established with the server, but then an error occurred during the login process.

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Article ID: 193697

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Updated On:

Products

CA Test Data Manager (Data Finder / Grid Tools)

Issue/Introduction

We are unable to start TDOD service. When the TDoD Service (GTService) attempts to establish a connection with the gtrep database, we see the following error thrown:

Service startup Error: TDOD service started on local computer started and then stopped. Some services stop automatically if they are not in use by other services.  

We see the following error in the tdod.log:

 Exception: A connection was successfully established with the server, but then an error occurred during the login process. (provider: SSL Provider, error: 0 - The client and server cannot communicate, because they do not possess a common algorithm.)

Cause

I researched the error we are seeing when attempting to connect to the gtrep repository database:

Exception: A connection was successfully established with the server, but then an error occurred during the login process. (provider: SSL Provider, error: 0 - The client and server cannot communicate, because they do not possess a common algorithm.)

This is an SQL Server (SQL Express) error message. My understanding is this error is typically seen when SSL3.0 and/or TLSv1.0 has been disabled, either on the client side or the SQL Server side, for releases prior to SQL Server 2016.

Apparently SQL Server (SQL Express) uses SSL for authentication encryption by default. Only recent releases of SQL Server started supporting TLSv1.2, so when TLSv1.0 and SSL3.0 are disabled, this error is typically seen when attempting to connect to the SQL Server database.

Environment

Release : 4.8

Component : CA Test Data Manager

Resolution


If you have Wireshark on the TDoD server, you could get a packet capture, to see what protocol we are attempting to use to authenticate to SQL Server (SQL Express). Then check the Windows registry, SCHANNEL Protocols, to ensure that protocol has not been disabled. These are located in:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols

Additional Information

There's a good article that covers this topic, and helps troubleshoot the issue. See http://sqlvandalism.com/2017/03/19/the-client-and-server-cannot-communicate-because-they-do-not-possess-a-common-algorithm/

Microsoft has patches available for older releases of SQL Server, in case you need to enable the TLSv1.2 protocol due to security concerns with TLSv1.0. See https://support.microsoft.com/en-us/help/3135244/tls-1-2-support-for-microsoft-sql-server.