Connect to existing MySQL database on server from local computer - mysql

Question

I am trying to connect to an existing mysql database on a linux server and scaffold tables in my project and working with them via EFCore.
I use this command line to scaffold :
dotnet ef dbcontext scaffold "server={IP};port={PORT};userid={USER_ID};password={PASSWORD};database={DB_NAME};" Pomelo.EntityFrameworkCore.MySql -o Models -f
But it shows this error to me:
Host '{MY_IP}' is not allowed to connect to this MySQL server
I am using Pomelo.EntityFrameworkCore.MySql library on .NET Core 2.1 SDK
What should I do?

Answer 1

If your MySQL instance is bound to the public IP address (you can check this by doing 3306 port scan for that IP - assuming MySQL is running on the standard port) then you need to grant privileges on the database for the user you are using as follows:
GRANT ALL PRIVILEGES ON <yourdb>.* TO `<youruser>`#`<yourip>` IDENTIFIED by '<yourpassword>';
After you have run this you need to run the FLUSH PRIVILEGES; command. Assuming all above conditions are met you should be able to access your DB remotely.

Answer 2

There are 2 things to understand before trying to connect.
1) Generally, databases are allowed to listen to local machine, ie localhost.
2) databases as mysql authentication comes in pair i.e. user#host_name.
So changing the way DB want you are really screwing security.
Now here is the way you can change MySQL listen for rest of world.
1) go to **my.cnf**, Check ‘**bind-address**’, comment this line. it
must be bind with `localhost` or `127.0.0.1`.
2) go to database MySQL, table users, column host replace
`localhost` to `"%"`, so the anyone from anywhere can connect.
3) `CREATE USER ‘root’#‘%’ IDENTIFIED BY ‘some_pass’`;
4) `GRANT ALL PRIVILEGES ON *.* TO ‘root’#‘%’;`
5) `FLUSH PRIVILEGES;`