Sometimes, it is convenient to have a UID in a Docker container match the UID in the host. You can’t do it all the time and it isn’t everyone’s cup of tea, but here’s how I made my MySQL user ID and gr

First, I always create a build script. i.e. Don’t just build your container from a Dockerfile via a straight command line. I call my build script “”. I also always use docker-compose. Tha

Here’s code from

if ! id -u mysql ; then
    sudo groupadd -g 400 mysql
    sudo useradd -Ms /bin/false -u 400 -g mysql mysql
MYSQLUID=`id -u mysql`
MYSQLGID=`id -g mysql`

If there is not already a mysql user, we’ll create one with UID and GID 400. You could use another number. I’ve just standardized on that one. Then, whether or not we created a UID, we retrieve the c

Here’s the build statement:

docker-compose build --build-arg MYSQLUID=$MYSQLUID --build-arg MYSQLGID=$MYSQLGID

And here’s an excerpt from Dockerfile:

FROM ubuntu:18.04
RUN id mysql || ( sudo groupadd -g 400 mysql &&  sudo useradd -Ms /bin/false -u 400 -g mysql mysql )
RUN apt-get -y install mysql-server