Troubleshoot a development environment

Choose another MediaWiki checkout

Clear the saved code directory to let the setup wizard ask for it again:

mw dev env delete MEDIAWIKI_VOLUMES_CODE
mw dev mediawiki create

mw dev env clear clears all context variables instead. Use it only when you want to configure the entire context again. Neither command is a substitute for destroying service containers or volumes.

To keep another checkout as a separate environment, use a different context:

mw dev --context another mediawiki create

Docker reports missing cgroup support

Messages such as Your kernel does not support cgroup memory limit or Unable to find cpu cgroup in mounts come from the Docker host setup. Check the installed Docker version and host configuration:

docker version
docker info

Updating an old Docker installation may resolve these warnings. When Docker runs inside a VM, check the Docker installation and cgroup support on that VM.

See setup, service configuration and MediaWiki debugging for related workflows.

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Read this guide offline with mw help guides dev troubleshooting.

Adapted from MediaWiki.org under CC BY-SA 4.0; see the linked page history for contributors.