Not able to connect MySQL DB. "Error establishing a database connection"

swapnil.salunke 2018-03-20 20:29:30 UTC #1

Keywords: MariaDB - Microsoft Azure - Technical issue - Connectivity (SSH/FTP)
Description:
Hi All,
I have a linux VM running on Azure and it has my wordpress instance running for multiple sites. Now everything was working fine until I rebooted server this morning in order to change IP Address. But After I rebooted All my websites started showing

Error establishing a database connection

So I did troubleshooting and googled for solution, based on different blogs I could find out below.
Check if MySQL is running using

bitnami@SGProdWeb:~$ sudo /etc/init.d/mysql status
* /usr/bin/mysqladmin  Ver 9.0 Distrib 5.5.57-MariaDB, for debian-linux-gnu on x86_64
Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.
 
Server version          5.5.57-MariaDB-1ubuntu0.14.04.1
Protocol version        10
Connection              Localhost via UNIX socket
UNIX socket             /var/run/mysqld/mysqld.sock
Uptime:                 1 hour 1 min 54 sec
 
Threads: 1  Questions: 81  Slow queries: 0  Opens: 13  Flush tables: 2  Open tables: 39  Queries per second avg: 0.021

But still not able to connect. when I enabled log on my php configuration I got below

Warning: mysqli_real_connect(): (HY000/1045): Access denied for user 'root'@'localhost' (using password: YES) in /opt/bitnami/apache2/*************/wp-includes/wp-db.php on line 1531.
This either means that the username and password information in your wp-config.php file is incorrect or we can’t contact the database server at 127.0.0.1. This could mean your host’s database server is down.


    Are you sure you have the correct username and password?
    Are you sure that you have typed the correct hostname?
    Are you sure that the database server is running?

Can anyone please help finding solution its urgent. Thank you in advance.

Not able to connect MySQL DB. “Error establishing a database connection”

jariza 2018-03-21 09:58:20 UTC #2

Hello @swapnil.salunke

Could you please check the database is running by using the command below?

sudo /opt/bitnami/ctlscript.sh status mariadb

In case it's not running, please run the command:

sudo /opt/bitnami/ctlscript.sh start mariadb

Once it's running, check your WP configuration file (/opt/bitnami/apps/wordpress/htdocs/wp-config.php). You'll find the lines below:

define('DB_USER', 'bn_wordpress');
define('DB_PASSWORD', 'XXXXXXXX');

Using the credentials found there, run the command:

/opt/bitnami/mysql/bin/mysql -u bn_wordpress -pXXXXXXXX

That would help you to detect if WP is able to connect to your database using the credentials available for it.

Please note that you need to substitute XXXXXXX with the actual password you found.

Best Regards,

Juan Ariza

Was my answer helpful? Click on

swapnil.salunke 2018-03-21 11:44:20 UTC #3

Thank you Jariza for your reply.

I used commands you suggested and got below output.

bitnami@MySiteUser:~$ sudo /opt/bitnami/ctlscript.sh status mariadb
usage: /opt/bitnami/ctlscript.sh help
       /opt/bitnami/ctlscript.sh (start|stop|restart|status)
       /opt/bitnami/ctlscript.sh (start|stop|restart|status) php-fpm
       /opt/bitnami/ctlscript.sh (start|stop|restart|status) apache

help       - this screen
start      - start the service(s)
stop       - stop  the service(s)
restart    - restart or start the service(s)
status     - show the status of the service(s)

so I ran below command again.

bitnami@MySiteUser :~$ sudo /etc/init.d/mysql status
 * /usr/bin/mysqladmin  Ver 9.0 Distrib 5.5.57-MariaDB, for debian-linux-gnu on x86_64
Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.

Server version          5.5.57-MariaDB-1ubuntu0.14.04.1
Protocol version        10
Connection              Localhost via UNIX socket
UNIX socket             /var/run/mysqld/mysqld.sock
Uptime:                 6 min 31 sec

Threads: 1  Questions: 82  Slow queries: 0  Opens: 13  Flush tables: 2  Open tables: 39  Queries per second avg: 0.209

bitnami@MySiteUser:~$ sudo /opt/bitnami/ctlscript.sh start mariadb
usage: /opt/bitnami/ctlscript.sh help
       /opt/bitnami/ctlscript.sh (start|stop|restart|status)
       /opt/bitnami/ctlscript.sh (start|stop|restart|status) php-fpm
       /opt/bitnami/ctlscript.sh (start|stop|restart|status) apache

help       - this screen
start      - start the service(s)
stop       - stop  the service(s)
restart    - restart or start the service(s)
status     - show the status of the service(s)

bitnami@MySiteUser:~$ sudo /opt/bitnami/mysql/bin/mysql -u <user> -p <password>.
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/opt/bit      nami/mysql/tmp/mysql.sock' (2)

Thanks in advance.

jariza 2018-03-22 09:25:25 UTC #4

Hi @swapnil.salunke

It seems your stack doesn't include MariaDB/MySQL. Are you using a Multi Tier solution? Please note the databas is running on a different machine on this kind of solutions.

More information in the link below:
https://docs.bitnami.com/azure-templates/apps/wordpress

Best Regards,

Juan Ariza

system 2018-04-05 09:25:45 UTC #5

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.

Bitnami provides free all-in-one installers, virtual machines and cloud images for popular open source applications. Get them now!