For more frequently asked questions (FAQ) see GitHub and Stackoverflow


Debug toolbar visible with YII_DEBUG=0

Solution Set YII_ENV=dev which is the variable responsible for the debug toolbar.

AssetManager warning

PHP Warning – yii\base\ErrorException

Cannot use a scalar value as an array
1. in /app/vendor/yiisoft/yii2/web/AssetManager.php

:warning: Fix Check your application for missing asset files or configuration.


Slow or hanging updates

If you're experiencing slow updates, check what's going on in detail with

composer -vvv update

Can't use @dev or dev-master packages

You need to use https://getcomposer.org/doc/articles/aliases.md, see also https://github.com/dmstr/yii2-cms-metapackage/issues/1

config settings

"asset-pattern-skip-version": "(-build|-patch)"


Port is already allocated

ERROR: Cannot start container 88b754d7e46aca58961ef0a049216f0e7331e35ba905d84fab01016a4797a779: failed to create endpoint appdev_mariadb_1 on network bridge: Bind for failed: port is already allocated

Remove or change your port mapping.

Can't push to private registry

See also issue on GitHub

Solution Add the nameserver on your boot2docker vm

echo "nameserver" > /etc/resolv.conf && sudo /etc/init.d/docker restart

VM harddisk out of space

See https://github.com/chadoe/docker-cleanup-volumes

docker run -v /var/run/docker.sock:/var/run/docker.sock -v /var/lib/docker:/var/lib/docker --rm martin/docker-cleanup-volumes

Service 'php' failed to build

Pulling repository docker.io/phundament/php-one
ERROR: Service 'php' failed to build: Network timed out while trying to connect to https://index.docker.io/v1/repositories/phundament/php-one/images. You may want to check your internet connection or if you are behind a proxy.
make: *** [build] Error 1

MySQL connection takes more than 5 seconds

Check your DNS settings, restart VM with docker-machine.

Can not connect to hosts on private networks

May be caused by overlapping subnets, as workaround is to remove networks with docker network ls -q | xargs docker rnetwork rm.

Cleanup volumes

see https://github.com/chadoe/docker-cleanup-volumes

Cleanup images and containers

docker run \
	-it \
	-v /var/run/docker.sock:/var/run/docker.sock \
	yelp/docker-custodian \
		dcgc --max-image-age=30d --max-container-age=1d --dry-run

Registry Login

Interactive login

docker login your-registry.example.com

Login docker CLI

docker login --username=${YOUR_USER} --password=${YOUR_PASS} your-registry.example.com

Note! Check if Docker saves the credentials locally in ~/.docker

Slow running tests

  • check DNS settings
  • check shared memory settings for Selenium container (/dev/shm)
  • removed unnecessary host-volumes

Failing Mailcatcher tests

Use a tagged image matching the codeception module version

image: tophfr/mailcatcher:0.6.5_2

chown commands in Dockefile

For every file, which is "chownd" a copy is created...

The filesystem has to copy up the the file into the new layer so that it can be chowned.


Gitlab CI Server


In case of weird errors you have the following workaround options, which you should try from to bottom:

  • Retry
  • Run a clean-script from time to time.
  • Use a different COMPOSE_PROJECT_NAME name for the CI jobs.
  • Clean project build folder via NAS
  • Clean project build folder via SSH to runner host and docker exec -it runner-x bash
  • Restart Docker daemon (sudo service docker restart and docker start runner-a runner-b ...
  • Move the project to another runner
  • Create a new runner
  • Reboot the runner-host (runners should have restart=always policy)
  • Recreate the runner-host (last resort)


$ bash build/scripts/deploy.sh
Username: EOF

Build variables like REGISTRY_USER not set.

SSH protocol error

> fatal: protocol error: bad line length character: No s

Check SSH key and correct spelling.

Todo: How to allow artifacts? ... cp to tmp and cp from tmp (EXPERIMENTAL!)


Running docker-compose on Windows can be painfully, because at least up to version 1.8.0-RC2 there's no interactive mode for commands like exec or run which renders them pretty unusable for development.

As a workaround you can use docker exec -it appname_php_1 bash to start a bash in a PHP container.

We recommend to run Docker CLI tools from a Linux VM on Windows.

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