How to deal with state "Exit 0" in Docker

Question

I have build a Docker image and afterwards run a container using Docker Compose. The following command will do the job for me:

docker-compose up -d

I have restarted the PC and now I want to start the previous container that I've created before. So I have tried the following command:

$ docker-compose start 
Starting php-apache ... done

Apparently it works but it doesn't as per the output for the following command:

$ docker-compose ps
          Name                         Command               State    Ports 
---------------------------------------------------------------------------
php55devwork_php-apache_1   /bin/sh -c bash -C '/usr/l ...   Exit 0        

For sure something is wrong and I am trying to find out what.

• How do I find why the command is failing?
• Is there any place where I could see a log file or something that help me to identify and fix the error?

Here is the repository if you want to give it a try.

Update

If I remove the container: docker rm <container-id> and recreate it by running docker-compose up -d --build it works again.

Update #1

I am not able to see such weird characters:

Answer 1

This is what helped me to resolve this issue: Under one of your services in the docker-compose yaml file, type in the following:

tty: true so it'll look like

version: '3'

services: 
   web: 
     tty: true

Hopefully this helps someone; thumps up if it helps you :)

Answer 2

I took a look into your Docker github and setup_php_settings on line (line n. 27) there is source /etc/apache2/envvars && exec /usr/sbin/apache2 -DFOREGROUND

and that runs apache2 on foreground so it shouldn't exit with status code 0.

But it seems to me like your setup_php_settings contains some weird character (when I run your image with compose) (original is one on right side) weird character I have changed it to new lines and it worked for me. Let us know if it helped.

If you want to debug your docker container you can run it without entrypoint like:

docker run -it yourImage bash

---

-- AFTER some investigation:

There were still some errors when I restart docker container - like in your case stopped container and start after reboot. There were problems: symbolic links already exist and apache2 has grumpy PID so we need to do something like in oficial php docker

This is full setup_php_settings worked for me after container restart.

#!/bin/bash -x
set -e

PHP_ERROR_REPORTING=${PHP_ERROR_REPORTING:-"E_ALL & ~E_DEPRECATED & ~E_NOTICE"}
sed -ri 's/^display_errors\s*=\s*Off/display_errors = On/g' /etc/php5/apache2/php.ini
sed -ri 's/^display_errors\s*=\s*Off/display_errors = On/g' /etc/php5/cli/php.ini
sed -ri "s/^error_reporting\s*=.*$//g" /etc/php5/apache2/php.ini
sed -ri "s/^error_reporting\s*=.*$//g" /etc/php5/cli/php.ini
echo "error_reporting = $PHP_ERROR_REPORTING" >> /etc/php5/apache2/php.ini
echo "error_reporting = $PHP_ERROR_REPORTING" >> /etc/php5/cli/php.ini

mkdir -p /data/tmp/php/uploads
mkdir -p /data/tmp/php/sessions
mkdir -p /data/tmp/php/xdebug

chown -R www-data:www-data /data/tmp/php*

ln -sf /etc/php5/mods-available/zz-php.ini /etc/php5/apache2/conf.d/zz-php.ini
ln -sf /etc/php5/mods-available/zz-php-directories.ini /etc/php5/apache2/conf.d/zz-php-directories.ini

# Add symbolic link to get Zend out of the current install dir
ln -sf /usr/share/php/libzend-framework-php/Zend/ /usr/share/php/Zend

a2enmod rewrite
php5enmod mcrypt

# Apache gets grumpy about PID files pre-existing
: "${APACHE_PID_FILE:=${APACHE_RUN_DIR:=/var/run/apache2}/apache2.pid}"
rm -f "$APACHE_PID_FILE"

source /etc/apache2/envvars && exec /usr/sbin/apache2 -DFOREGROUND "$@"

Answer 3

You can check logs with docker compose logs.

Looking through your repo, you have

ENTRYPOINT bash -C '/usr/local/bin/setup_php_settings';'bash'

which, without an interactive session, bash will exit immediately (with an exit code 0) after reading the end of file on stdin.

Answer 4

Normally getting an exit 0 should be a reason to celebrate, as it indicates that your command has ended successfully (http://www.tldp.org/LDP/abs/html/exit-status.html).

Having had a look at your Dockerfile it looks like, your just invoking bash in your entry point which then for sure will exit (as it is non blocking). In order to serve some data, you should rather be calling php (which is a blocking operation that keeps the container up), like done in the official docker files for php (see the CMD ["php", "-a"] at https://github.com/docker-library/php/blob/1c56325a69718a3e3cf76179e75d070b7e23da62/5.6/Dockerfile)