Solving a “communications link failure” with JDBC and MySQL [duplicate]

Answer 1

In case you are having problem with a set of Docker containers, then make sure that you do not only EXPOSE the port 3306, but as well map the port from outside the container -p 3306:3306. For docker-compose.yml:

version: '2'

services:
    mdb:
        image: mariadb:10.1
        ports:
            - "3306:3306"
        …

Answer 2

I faced this problem also.

As Soheil suggested, I went to php.ini file at the path C:\windows\php.ini , then I revised port number in this file.

it is on the line mysqli.default_port =..........

So I changed it in my java app as it's in the php.ini file,now it works fine with me.

Answer 3

If you are using MAMP PRO, the easy fix, which I really wish I had realized before I started searching the internet for days trying to figure this out. Its really this simple...

You just have to click "Allow Network Access to MySQL" from the MAMP MySQL tab.

Really, thats it.

Oh, and you MIGHT have to still change your bind address to either 0.0.0.0 or 127.0.0.1 like outlined in the posts above, but clicking that box alone will probably solve your problems if you are a MAMP user.

Answer 4

Go to Windows services in the control panel and start the MySQL service. For me it worked. When I was doing a Java EE project I got this error" Communication link failure". I restarted my system and then it worked.

After that I again got the same error even after restarting my system. Then I tried to open the MySQL command line console and login with root, even then it gave me an error.

Finally when I started the MySQL service from Windows services, it worked.

Answer 5

I was experiencing similar problem and the solution for my case was

1. changing bind-address = 0.0.0.0 from 127.0.0.1
2. changing url's localhost to localhost:3306

the thing i felt is we should never give up, i tried every options from this post and from other forums as well...happy it works @saurab

Answer 6

For Windows :- Goto start menu write , "MySqlserver Instance Configuration Wizard" and reconfigure your mysql server instance. Hope it will solve your problem.