Issue with client application connecting to SQL from remote location

Question

We setup a new virtual server at one of our clients and built a virtual machine running

Microsoft SQL Server Management Studio 10.50.2550.0
Microsoft Analysis Services Client Tools 10.50.2500.0
Microsoft Data Access Components (MDAC) 6.1.7601.17514
Microsoft MSXML 3.0 6.0 
Microsoft Internet Explorer 9.0.8112.16421
Microsoft .NET Framework 2.0.50727.5466
Operating System 6.1.7601

We moved the applications database to this server and I can connect to it from within the network without issue.  The client has remote users who access the application by a firewall rule that forwards a particular port # to the server.  When I point the firewall rule to the old server the remote users application connects to the old SQL server with out issue.  When I point the firewall rule to the new server the connection times out.  I can successfully connect to the new server via telnet from a remote computer via the specified port in the firewall rule.  I know the SQL server is listening properly on the port as the internal clients would not work if that was the case.   Anyone have an idea as to why a remote client can't connect?

Thanks,

Answer 1

What does your connection string look like? Does it have the port number?

Detailed troubleshooting steps at How to Troubleshoot Connecting to the SQL Server Database Engine

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Rick Byham, Microsoft, SQL Server Books Online, Implies no warranty

Answer 2

There are many reasons of SQL server connectivity issue. Refer checklist to find out the real cause of connectivity issue.

1. Check SQL services are running

2. Check SQL Browser service is running

3. Check remote connections are enabled

4. Network connectivity between database & application servers by TRACERT command

5. Check TCP/IP protocol enabled at SQL server

6. Check talent connectivity – telnet <IP address> <port no on SQL server running>

7. Check UDP port 1434 is open or not on SQL Server

8. Check firewall is running or not Check

9. If firewall running, SQL Server & UDP port must be added in exception in firewall

10. Run SQL Discovery report on machine SQL server installed, to check you are using correct instance name to connect( default \named) - http://mssqlfun.com/2013/02/26/sql-server-discovery-report/

http://mssqlfun.com/2012/09/28/check-list-for-sql-server-connectivity-issue/

Also share your connection string, you are trying to use along with full error message.

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Regards,
Rohit Garg
(My Blog)
This posting is provided with no warranties and confers no rights.
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