Issue
I am using Docker to create a dockerfile with mysql as the base image:
FROM mysql
#set root pass
ENV MYSQL_ROOT_PASSWORD password
#update linux
RUN apt-get update
#create database
RUN mysql -u root -ppassword -e "CREATE DATABASE dbname"
#install vim
RUN apt-get install vim -y
The dockerfile fails on the step where I try to create a database, it doesn't finish building and i receive this error:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'
When I remove the #create database run command the dockerfile will build and I am able to run a container from that image. I know that it isn't a problem with the mysql server as I can enter the container and run the mysql command manually with success and the service status is running.
Using an environment variable i.e MYSQL_ROOT_PASSWORD within the file also allows me to create a database successfully but this will only work with a single database, I need to be able to use the mysql command to make queries, such as creating additional databases / assigning users etc.
This may be because I need to specify the host and port of the docker container but this still does not allow me to connect
RUN mysql -u root -ppassword -h 127.0.0.1 -P 3308 -e "CREATE DATABASE dbname"
Strangely, doing this also often crashes the container and puts it in a state where it will crash again on start-up every time that I try to restart it again.
Solution
Had the very same problem: When starting the container and running a set of RUN instructions, or .sh or .sql scripts in /docker-entrypoint-initdb.d/ no connection to the database server could be established.
I found the solution by a comment of @wpalmer on the mysql-image:
The init scripts run by the entrypoint, internally, use the variable "${mysql[@]}" to call mysql (for example, when loading .sql files placed in the docker-entrypoint-initdb.d directory. Any .sh files which are processed by the entrypoint are included by "sourcing" them, meaning that variable is available for use by any .sh files which are run).
So what this means for you, instead of providing the plain mysql command with user, pass etc. as in
RUN mysql -u root -ppassword -e "CREATE DATABASE dbname"
use the placeholder instead:
RUN "${mysql[@]}" -e "CREATE DATABASE dbname"
Answered By - jotrocken Answer Checked By - Mildred Charles (WPSolving Admin)
