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Hi All,
Don't know if this is the right forum for this query, but couldn't find anything more suitable.
I have written a new app in VB.net as a front end to a mySQL database held on a PC on the LAN running Windows XP. This worked fine for a while. The PC running the mySQL server started locking up (XP errors, not mySQL errors according to the event logs), so I decided to have a go installing Ubuntu to run the mySQL server to see if that was more stable.
Ubuntu 11.10 is now installed, and mysql server is also running. I have imported the old sql database files and the mySQL workbench shows all tables are imported successfully.

HOWEVER, I cannot get my VB application to connect to the database now it resides on Ubuntu - just returns "Unable to connect to any of the specified MySQL hosts" when i try to open a connection. I am fairly new to Ubuntu and MySQL, and don't know if the fault lies with the O/S (a firewall config problem perhaps?) or if I need to do something different with mySQL.
I can ping the Ubuntu pc from the client pc and vice versa.
I have used ufw to open port 3306 on the server
The ufw logs do not show any errors when I try to connect from the client pc, so I don't think it's a firewall problem (but could be wrong).
I thought it may be something to do with the usernames I use in the connection string, but when I change these (deliberately use the wrong password for example) I get the same message, rather than a username/password error

Is anyone else using a client PC running Windows (W7 or XP) to connect to a mySQL database running on a Ubuntu server?
All help gratefully received. (again - sorry if this is posted in wrong forum)

Toomutch

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Last Post by toomutch
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Do you mean I should install the adapter/connector on the client, or on the server?

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On the client.

But you may also need to configure the mysql server to allow incoming connections to other than localhost.
In the permission table. (If I'm not mistaken).

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Have installed fresh connector on the client (6.4.4 to 6.5.4), but no difference.
The username I have specified on the server has 'limit connectivity to hosts matching' set to % as I understood this means 'remote' - is this correct?

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That is the wildcard character.

That means that you are allowing any connection from any IP.

Do you have a user setup (with access to the database) on the Ubuntu machine?

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It might also be a good idea to specify the port in the connectionstring, even if it's the default one.
I found a bug report regarding that error message on MySql.com that suggested this could be the problem.

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Thanks for the suggestion Oxiegen, I have added "port=3306" to the connection string, but no difference.

I have already added a user from the 'server administration' panel on the workbench, and have ticked the same boxes as when it was originally on the XP machine. I already had mysql installed on my dev laptop for testing, so I changed my connection string back to use the "127.0.0.1" IP address and this connects fine. I think that this proves that my VB Net coding is correct, and that my connection string is correct. It therefore points to the Ubuntu server as being the problem, so I did a bit more testing: if I remove the user from the Ubuntu server, (workbench, server administration, security, users and privileges - remove) and try to connect I still get the same message (i.e. Unable to connect to any of the specified MySQL hosts.) I don't get any username / password errors. Does this have any relevance?

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did some more digging and eventually found the problem. In the /etc/mysql/my.cnf on the ubuntu server, the bind-address was set to 127.0.0.1 by default, so was only looking for connections from itself. I amended the file to 'bind-address = 0.0.0.0' and all is fine and dandy! Thanks for the suggestions from those who contributed - don't think I would have got there without you.

Toomutch

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