Assistance, please

[lynxreign]

To all the computer-nerdy/knowledgeable people out there,

I don't normally do much with server setup, but I think it may be at the root of a problem I'm having with some programs.

We have a centrally stored databse that 2 of the programs I inherited here use on startup. They are automatically accessed behind the scenes and thus are difficult for users to assist in debugging. They just know that the program doesn't start.

Normally, I'd just run it myself and try to track it down, therein lies the problem. They can run it in the building with no problems. If they try to run the program on VPN, it crashes. That's for each of the programs and they access the same database at the same time in the program: on startup.

I think, after some research, that the server this SQL Server database resides upon must be specially configured to allow database connectivity over VPN. Is this crazy talk or am I barking up the right tree?

Sincerely,

Lynxreign

Comments

[wizardru.livejournal.com]

I'd need some more details on the application. How is it connecting to the databases? If it's a MS SQL database, you have two ways to connect to it: windows authentication or SQL authentication. Assuming it uses windows credentials, it could be a conflict between the credentials used on the VPN and the local credentials when connecting. If the clients use a specific alternate log-in for the VPN, this may also be the problem, possibly from a access-rights issue.

I would first see if you can establish a SQL connection between the client and the application, first. It's also quite possible that the VPN they are using is specifically blocking certain ports and only explicitly allowing specific applictions to run (again this also may be a right issue through the VPN appliance based on group membership).

[lynxreign.livejournal.com]

It is a MS SQL Database.
I do not know how we handle VPN credentials here. I'll make that a point to find out when making my inquiry. There is nothing in the program that differentiates between local and VPN access for log-in.

Either way, this is a problem to be solved Server-Side, yes?

[wizardru.livejournal.com]

I won't say positively yes, but I'd start with that assumption. A VPN client tunnels all their traffic over the VPN protocol (usually either PPTP or L2TP), so as long as they can connect, all traffic SHOULD pass between the home machine and the corporate network. Establishing a connection between client and server is the first way to start to determine where the problem lies. The possibility exists of some DNS resolution problem, which would prevent the local client from connecting over the VPN, if it can't resolve the server's name.

Your first line of defense should be determining whether or not the problem is a traffic problem or rights problem. I'd start with the VPN authentication and permissions. That's a firewall or network problem. If they have blocking rules (because the VPN server is in a DMZ), then that's still a server/network problem.

I would start from the network, down to the server and then down to the client...with the one caveat that you should verify that connectivity exists between the client and the server itself.

[lynxreign.livejournal.com]

Thank You Mentok.

And based on the distance from which you were diagnosing and the lack of concrete details, I'd be astonished if you were indeed able to provide a positive yes.