Xdebug (inside Docker container) ignoring XDEBUG_CONFIG environment variable

I had the same problem. My image was based on nimmis/alpine-apache-php7/. I found that the image was using supervisor to start processes. supervisor has no knowledge of the Docker environment variables.

The convention to tell supervisor that a process needs to be run, is to create a run script at /etc/sv/{process}/run. A script like this was used to start Apache. I needed to change the script so that it would import Docker environment variables before starting Apache.

The docs for the base image explain the convention for importing Docker environment:

If you need environment variables from the docker command line (-e,--env=[]) add

source /etc/envvars

before you use them in the script file

So I created my own custom run script for Apache — I added source /etc/envvars just before execution of httpd.

I overwrote the original run script, by adding a simple COPY to my Dockerfile:

COPY apache-run.sh /etc/sv/apache2/run

This successfully ensured that my $XDEBUG_CONFIG was visible to httpd at the time it was launched. I was able to confirm that this affected my PHP configuration, by printing phpinfo(); in a webpage.

Did you do a phpinfo();? That should tell you the settings used.

I had the same problem... took me forever to figure out. Are you using xdebug.remote_connect_back=1? If so remove that line.

My nginx proxy was forwarding an IP through (which was wrong) and so the ip set in XDEBUG_CONFIG was being ignored.

For me it was a different problem using the official PHP-FPM-Alpine docker image (FROM php:7-fpm-alpine)

I needed to add the XDEBUG-CONFIG to the fpm pool config:env[XDEBUG_CONFIG] = $XDEBUG_CONFIG

See full config https://github.com/attrib/docker-symfony