README.rst

Open edX Devstack

Get up and running quickly with Open edX services.

This project replaces the older Vagrant-based devstack with a multi-container approach driven by Docker Compose.

A Devstack installation includes the following Open edX components by default:

• The Learning Management System (LMS)
• Open Response Assessments (ORA2), among other LMS plug-ins.
• Open edX Studio
• Discussion Forums
• E-Commerce
• Credentials
• Notes
• Course Discovery
• Open edX Search
• A demonstration Open edX course
• The Publisher and Gradebook micro-frontends

It also includes the following extra components:

• XQueue
• The components needed to run the Open edX Analytics Pipeline. This is the primary extract, transform, and load (ETL) tool that extracts and analyzes data from the other Open edX services.
• The Learning micro-frontend (A.K.A the new Courseware experience)
• The Program Console micro-frontend
• edX Registrar service.

Table of Contents

• Where to Find Help
• Prerequisites
• Using the Latest Images
• Getting Started
• Usernames and Passwords
• Service List
• Useful Commands
• Troubleshooting: General Tips
• Troubleshooting: Common Issues
• Troubleshooting: Performance
• Advanced Configuration Options

Where to Find Help

There are a number of places to get help, including mailing lists and real-time chat. Please choose an appropriate venue for your question. This helps ensure that you get good prompt advice, and keeps discussion focused. For details of your options, see the Community pages.

Prerequisites

You will need to have the following installed:

• make
• Python 3
• Docker

This project requires Docker 17.06+ CE. We recommend Docker Stable, but Docker Edge should work as well.

NOTE: Switching between Docker Stable and Docker Edge will remove all images and settings. Don't forget to restore your memory setting and be prepared to provision.

For macOS users, please use Docker for Mac. Previous Mac-based tools (e.g. boot2docker) are not supported.

Since a Docker-based devstack runs many containers, you should configure Docker with a sufficient amount of resources. We find that configuring Docker for Mac with a minimum of 2 CPUs and 8GB of memory does work.

Docker for Windows may work but has not been tested and is not supported.

If you are using Linux, use the overlay2 storage driver, kernel version 4.0+ and not overlay. To check which storage driver your docker-daemon uses, run the following command.

docker info | grep -i 'storage driver'

Please note

You should run all make commands described below on your local machinge, not from within a Virtual Machine, as these commands are meant to stand up a VM-like environment using Docker containers.

However, you may want to run the make commands from within a Python 3 virtual environment, as described in Getting Started. This will keep the Python packages required for Devstack separate from the ones installed globally on your system.

Using the Latest Images

New images for our services are published frequently. Assuming that you've followed the steps in Getting Started below, run the following sequence of commands if you want to use the most up-to-date versions of all default devstack images.

make down
make dev.pull
make dev.up

This will stop any running devstack containers, pull the latest images, and then start all of the devstack containers.

If you wish to pull only images relevant to certain services, you can run make dev.pull.<services>. For example, the following only only pulls images of E-Commerce and Credentials, as well as their dependencies (like LMS).

make dev.pull.ecommerce+credentials

To further save time, make dev.pull.without-deps.<services> pulls the images for the specified service and nothing else.

make dev.pull.without-deps.ecommerce+credentials

Getting Started

The default devstack services can be run by following the steps below. For analyticstack, follow Getting Started on Analytics.

1. Install the requirements inside of a Python virtualenv.

   make requirements

   This will install docker-compose and other utilities into your virtualenv.

2. The Docker Compose file mounts a host volume for each service's executing code. The host directory defaults to be a sibling of this directory. For example, if this repo is cloned to ~/workspace/devstack, host volumes will be expected in ~/workspace/course-discovery, ~/workspace/ecommerce, etc. These repos can be cloned with the command below.

   make dev.clone  # or, `make dev.clone.https` if you don't have SSH keys set up.

   You may customize where the local repositories are found by setting the DEVSTACK_WORKSPACE environment variable.

   (macOS only) Share the cloned service directories in Docker, using Docker -> Preferences -> File Sharing in the Docker menu.

3. Pull any changes made to the various images on which the devstack depends.

   make dev.pull

3. Optional: You have an option to use NFS on MacOS which may improve the performance significantly. To set it up ONLY ON MAC, do

   make dev.nfs.setup

4. Run the provision command, if you haven't already, to configure the various services with superusers (for development without the auth service) and tenants (for multi-tenancy).

   NOTE: When running the provision command, databases for ecommerce and edxapp will be dropped and recreated.

   The username and password for the superusers are both edx. You can access the services directly via Django admin at the /admin/ path, or login via single sign-on at /login/.

   Default:

   make dev.provision

   Provision using docker-sync:

   make dev.sync.provision

   Provision using NFS:

   make dev.nfs.provision

   This is expected to take a while, produce a lot of output from a bunch of steps, and finally end with Provisioning complete!

5. Start the services. This command will mount the repositories under the DEVSTACK_WORKSPACE directory.

   NOTE: it may take up to 60 seconds for the LMS to start, even after the make dev.up command outputs done.

   Default:

   make dev.up

   Start using docker-sync:

   make dev.sync.up

   Start using NFS:

   make dev.nfs.up

After the services have started, if you need shell access to one of the services, run make dev.shell.<service>. For example to access the Catalog/Course Discovery Service, you can run:

make dev.shell.discovery

To see logs from containers running in detached mode, you can either use "Kitematic" (available from the "Docker for Mac" menu), or by running the following:

make dev.logs

To view the logs of a specific service container run make dev.logs.<service>. For example, to access the logs for Ecommerce, you can run:

make dev.logs.ecommerce

For information on the supported make commands, you can run:

make help

Usernames and Passwords

The provisioning script creates a Django superuser for every service.

Email: [email protected]
Username: edx
Password: edx

The LMS also includes demo accounts. The passwords for each of these accounts is edx.

Account	Description
[email protected]	An LMS and Studio user with course creation and editing permissions. This user is a course team member with the Admin role, which gives rights to work with the demonstration course in Studio, the LMS, and Insights.
[email protected]	A student account that you can use to access the LMS for testing verified certificates.
[email protected]	A student account that you can use to access the LMS for testing course auditing.
[email protected]	A student account that you can use to access the LMS for testing honor code certificates.

Service List

These are the edX services that Devstack can provision, pull, run, attach to, etc. Each service is accessible at localhost on a specific port. The table below provides links to the homepage, API root, or API docs of each service, as well as links to the repository where each service's code lives.

The services marked as Default are provisioned/pulled/run whenever you run make dev.provision / make dev.pull / make dev.up, respectively.

The extra services are provisioned/pulled/run when specifically requested (e.g., make dev.provision.xqueue / make dev.pull.xqueue / make dev.up.xqueue). Alternatively, you can run these by modifying the DEFAULT_SERVICES option as described in the Advanced Configuration Options section.

Service	URL	Type	Role
lms	http://localhost:18000/	Python/Django	Default
studio	http://localhost:18010/	Python/Django	Default
forum	http://localhost:44567/api/v1/	Ruby/Sinatra	Default
discovery	http://localhost:18381/api-docs/	Python/Django	Default
ecommerce	http://localhost:18130/dashboard/	Python/Django	Default
credentials	http://localhost:18150/api/v2/	Python/Django	Default
edx_notes_api	http://localhost:18120/api/v1/	Python/Django	Default
frontend-app-publisher	http://localhost:18400/	MFE (React.js)	Default
gradebook	http://localhost:1994/	MFE (React.js)	Default
registrar	http://localhost:18734/api-docs/	Python/Django	Extra
program-console	http://localhost:1976/	MFE (React.js)	Extra
frontend-app-learning	http://localhost:2000/	MFE (React.js)	Extra
xqueue	http://localhost:18040/api/v1/	Python/Django	Extra
analyticspipeline	http://localhost:4040/	Python	Extra
marketing	http://localhost:8080/	PHP/Drupal	Extra

Useful Commands

Abbreviated versions of commands

You may notice that many Devstack commands come in the form dev.ACTION.SERVICE. As examples:

make dev.up.registrar
make dev.shell.lms
make dev.attach.studio
make dev.down.credentials
make dev.migrate.edx_notes_api
make dev.static.ecommerce
make dev.restart-devserver.forum
make dev.logs.gradebook

In general, these commands can also be given in the form SERVICE-ACTION, which saves some keystrokes and is often more friendly for automatic command-completion by hitting TAB. As examples:

make registrar-up
make lms-shell
make studio-attach
make credentials-down
make edx_notes_api-migrate
make ecommerce-static
make forum-restart-devserver
make gradebook-logs

Bringing up fewer services

make dev.up can take a long time, as it starts all services, whether or not you need them. To instead only start a single service and its dependencies, run make dev.up.<services>. For example:

make dev.up.lms

That above command will bring up LMS (along with Memcached, MySQL, DevPI, et al), but it will not bring up Credentials, Studio, or E-Commerce or any of the other default services.

You can also specify multiple services:

make dev.up.ecommerce+studio

Pulling fewer images

Similarly, make dev.pull can take a long time, as it pulls all services' images, whether or not you need them. To instead only pull images required by your service and its dependencies, run make dev.pull.<services>. For example:

make dev.pull.discovery

Restarting servers and containers

Sometimes you may need to manually restart a particular application server To do so, the quickest command to run is make dev.restart-devserver.<service>, which restarts the Django/Sinatra server inside the container without restarting the container itself. For example:

make dev.restart-devserver.credentials

This can be helpful, for example, if automatic code reloading isn't working for some reason.

If you wish to restart the container itself, which takes a bit longer but may resolve a larger class of issues, use make dev.restart-container.<services>. For example:

make dev.restart-container.credentials

Frequently Asked Questions

How do I run the images for a named Open edX release?

1. Set the OPENEDX_RELEASE environment variable to the appropriate image tag; "hawthorn.master", "zebrawood.rc1", etc. Note that unlike a server install, OPENEDX_RELEASE should not have the "open-release/" prefix.
2. Check out the appropriate branch in devstack, e.g. git checkout open-release/ironwood.master
3. Use make dev.checkout to check out the correct branch in the local checkout of each service repository once you've set the OPENEDX_RELEASE environment variable above.
4. make dev.pull to get the correct images.

All make target and docker-compose calls should now use the correct images until you change or unset OPENEDX_RELEASE again. To work on the master branches and latest images, unset OPENEDX_RELEASE or set it to an empty string.

How do I define my own local targets?

If you'd like to add some convenience make targets, you can add them to a local.mk file, ignored by git.

How do I make payments?

The ecommerce image comes pre-configured for payments via CyberSource and PayPal. Additionally, the provisioning scripts add the demo course (course-v1:edX+DemoX+Demo_Course) to the ecommerce catalog. You can initiate a checkout by visiting http://localhost:18130/basket/add/?sku=8CF08E5 or clicking one of the various upgrade links in the LMS. The following details can be used for checkout. While the name and address fields are required for credit card payments, their values are not checked in development, so put whatever you want in those fields.

• Card Type: Visa
• Card Number: 4111111111111111
• CVN: 123 (or any three digits)
• Expiry Date: 06/2025 (or any date in the future)

PayPal (same for username and password): [email protected]

How do I develop on an installed Python package?

If you want to modify an installed package – for instance edx-enterprise or completion – clone the repository in ~/workspace/src/your-package. Next, ssh into the appropriate docker container (make lms-shell), run pip install -e /edx/src/your-package, and restart the service.

How do I upgrade Python packages?

Unlike the node_modules directory, the virtualenv used to run Python code in a Docker container only exists inside that container. Changes made to a container's filesystem are not saved when the container exits, so if you manually install or upgrade Python packages in a container (via pip install, paver install_python_prereqs, etc.), they will no longer be present if you restart the container. (Devstack Docker containers lose changes made to the filesystem when you reboot your computer, run make down, restart or upgrade Docker itself, etc.) If you want to ensure that your new or upgraded packages are present in the container every time it starts, you have a few options:

• Merge your updated requirements files and wait for a new edxops Docker image for that service to be built and uploaded to Docker Hub. You can then download and use the updated image (for example, via make dev.pull.<service>). The discovery and edxapp images are built automatically via a Jenkins job. All other images are currently built as needed by edX employees, but will soon be built automatically on a regular basis. See building images for devstack for more information.
• You can update your requirements files as appropriate and then build your own updated image for the service as described above, tagging it such that docker-compose will use it instead of the last image you downloaded. (Alternatively, you can temporarily edit docker-compose.yml to replace the image entry for that service with the ID of your new image.) You should be sure to modify the variable override for the version of the application code used for building the image. See How do I build images?. for more information.
• You can temporarily modify the main service command in docker-compose.yml to first install your new package(s) each time the container is started. For example, the part of the studio command which reads ...&& while true; do... could be changed to ...&& pip install my-new-package && while true; do....
• In order to work on locally pip-installed repos like edx-ora2, first clone them into ../src (relative to this directory). Then, inside your lms shell, you can pip install -e /edx/src/edx-ora2. If you want to keep this code installed across stop/starts, modify docker-compose.yml as mentioned above.

How do I upgrade Node.js packages?

JavaScript packages for Node.js are installed into the node_modules directory of the local git repository checkout which is synced into the corresponding Docker container. Hence these can be upgraded via any of the usual methods for that service (npm install, paver install_node_prereqs, etc.), and the changes will persist between container restarts.

How do I rebuild static assets?

Optimized static assets are built for all the Open edX services during provisioning, but you may want to rebuild them for a particular service after changing some files without re-provisioning the entire devstack. To do this, run the make dev.static.<service> target. For example:

make dev.static.credentials

To rebuild static assets for all service containers:

make dev.static

How do I connect to the databases from an outside editor?

To connect to the databases from an outside editor (such as MySQLWorkbench), first uncomment these lines from docker-compose.yml's mysql section:

ports:
  - "3506:3306"

Then connect using the values below. Note that the username and password will vary depending on the database. For all of the options, see provision.sql.

• Host: localhost
• Port: 3506
• Username: edxapp001
• Password: password

If you have trouble connecting, ensure the port was mapped successfully by running make dev.ps and looking for a line like this: edx.devstack.mysql docker-entrypoint.sh mysql ... Up 0.0.0.0:3506→3306/tcp.

How do I run the edX.org Drupal Marketing Site?

The edX.org marketing site built on Drupal is being deprecated, but it can still be run via Devstack. See the Marketing Site instructions for details on getting it up and running. This will not be useful to those outside of edX, Inc.

How do I build the service images myself?

See the instructions for building images for devstack.

How do I create relational database dumps?

See the instructions for updating relational database dumps.

How do I keep my database up to date?

To run Django migrations for a particular service, bring up the service and use make dev.migrate.<service>. For example:

make dev.up.studio
make dev.migrate.studio

To run migrations for all services at once, run:

make dev.up
make dev.migrate

Alternatively, you can discard and rebuild the entire database for all devstack services by re-running make dev.provision or make dev.sync.provision as appropriate for your configuration. Note that if your branch has fallen significantly behind master, it may not include all of the migrations included in the database dump used by provisioning. In these cases, it's usually best to first rebase the branch onto master to get the missing migrations.

How do I access a database shell?

To access a MongoDB shell, run the following commands:

make dev.shell.mongo
mongo

To access the MySQL shell for a particular database, run:

make dev.shell.mysql
mysql
use <database>;

Equivalently, you can use the command make dev.dbshell.<database> as a shortcut. For example, this will put you in a MySQL shell using the E-Commerce database:

make dev.dbshell.ecommerce

How do I create new migrations?

For LMS, log into the LMS shell and run the makemigrations command with the devstack_docker settings:

make dev.shell.lms
./manage.py lms makemigrations <appname> --settings=devstack_docker

For Studio, it is similar:

make dev.shell.studio
./manage.py cms makemigrations <appname> --settings=devstack_docker

Finally, for any other service, run:

make dev.shell.<service>
./manage.py makemigrations <appname>

Also, make sure you are aware of the Django Migration Don'ts as the edx-platform is deployed using the red-black method.

Switching branches

You can usually switch branches on a service's repository without adverse effects on a running container for it. The service in each container is using runserver and should automatically reload when any changes are made to the code on disk. However, note the points made above regarding database migrations and package updates.

When switching to a branch which differs greatly from the one you've been working on (especially if the new branch is more recent), you may wish to halt the existing containers via make down, pull the latest Docker images via make dev.pull.<service>, and then re-run make dev.provision or make dev.sync.provision in order to recreate up-to-date databases, static assets, etc.

If making a patch to a named release, you should pull and use Docker images which were tagged for that release.

Changing LMS/Studio settings

LMS and Studio (a.k.a. CMS) read many configuration settings from the container filesystem in the following locations:

• /edx/app/edxapp/lms.env.json
• /edx/app/edxapp/lms.auth.json
• /edx/app/edxapp/cms.env.json
• /edx/app/edxapp/cms.auth.json

Changes to these files will not persist over a container restart, as they are part of the layered container filesystem and not a mounted volume. However, you may need to change these settings and then have the LMS or Studio pick up the changes.

After changing settings, you can restart the LMS/Studio process without restarting the container by running the following on your host machine:

make dev.restart-devserver.lms     # For LMS
make dev.restart-devserver.studio  # For Studio/CMS

How do I integrate with PyCharm?

See the Pycharm Integration documentation.

What is DevPI and how does it affect Devstack?

LMS and Studio use a devpi container to cache PyPI dependencies, which speeds up several Devstack operations. See the devpi documentation.

Testing and Debugging

Debugging using PDB

It's possible to debug any of the containers' Python services using PDB. To do so, start up the containers as usual with:

make dev.up

This command starts each relevant container with the equivalent of the '--it' option, allowing a developer to attach to the process once the process is up and running.

To attach to a container and its process, use make dev.attach.<service>. For example:

make dev.attach.lms

Set a PDB breakpoint anywhere in the code using one of the following:

breakpoint()                # Works in Python >= 3.7
import pdb;pdb.set_trace()  # Workg in any version of Python

and your attached session will offer an interactive PDB prompt when the breakpoint is hit.

You may be able to detach from the container with the Ctrl-P, Ctrl-Q key sequence. If that doesn't work, you will have either close your terminal window or bring the service down with:

make dev.down.<service>

You can bring that same service back up with:

make dev.up.<service>

Running LMS and Studio Tests

After entering a shell for the appropriate service via make lms-shell or make studio-shell, you can run any of the usual paver commands from the edx-platform testing documentation. Examples:

paver run_quality
paver test_a11y
paver test_bokchoy
paver test_js
paver test_lib
paver test_python

Tests can also be run individually. Example:

pytest openedx/core/djangoapps/user_api

Tests can also be easily run with a shortcut from the host machine, so that you maintain your command history:

./in lms pytest openedx/core/djangoapps/user_api

Connecting to Browser

If you want to see the browser being automated for JavaScript or bok-choy tests, you can connect to the container running it via VNC.

Browser	VNC connection
Firefox (Default)	vnc://0.0.0.0:25900
Chrome (via Selenium)	vnc://0.0.0.0:15900

On macOS, enter the VNC connection string in the address bar in Safari to connect via VNC. The VNC passwords for both browsers are randomly generated and logged at container startup, and can be found by running make vnc-passwords.

Most tests are run in Firefox by default. To use Chrome for tests that normally use Firefox instead, prefix the test command with SELENIUM_BROWSER=chrome SELENIUM_HOST=edx.devstack.chrome.

Running End-to-End Tests

To run the base set of end-to-end tests for edx-platform, run the following make target:

make e2e-tests

If you want to use some of the other testing options described in the edx-e2e-tests README, you can instead start a shell for the e2e container and run the tests manually via paver:

make e2e-shell
paver e2e_test --exclude="whitelabel\|enterprise"

The browser running the tests can be seen and interacted with via VNC as described above (Firefox is used by default).

Troubleshooting: General Tips

If you are having trouble with your containers, this sections contains some troubleshooting tips.

Check the logs

If a container stops unexpectedly, you can look at its logs for clues:

make dev.logs.<service>

Update the code and images

Make sure you have the latest code and Docker images.

Pull the latest Docker images by running the following command from the devstack directory:

make dev.pull

Pull the latest Docker Compose configuration and provisioning scripts by running the following command from the devstack directory:

git pull

Lastly, the images are built from the master branches of the application repositories (e.g. edx-platform, ecommerce, etc.). Make sure you are using the latest code from the master branches, or have rebased your branches on master.

Clean the containers

Sometimes containers end up in strange states and need to be rebuilt. Run make dev.down to remove all containers and networks. This will NOT remove your data volumes.

Reset to a sane state

Sometimes you just aren't sure what's wrong, if you would like to hit the reset button run make dev.reset.

Running this command will perform the following steps:

• Bring down all containers
• Reset all git repositories to the HEAD of master
• Pull new images for all services
• Compile static assets for all services
• Run migrations for all services

This does not delete your data and you do not need to re-provision after running it. It can be good to try this before asking for help.

Re-provision individual database(s)

If you botched a migration for a service, or just want to start with a clean database for a service without re-provisioning every single service, you can drop that service's database and re-provision it.

1. Drop the correct database (see provision.sql for the full list of database names):

make dev.drop-db.<database>

2. Re-provision the service(s):

make dev.provision.<services>

For example, if you messed up just your Course Discovery and Registrar databases, you could try running:

make dev.drop-db.discovery
make dev.drop-db.registrar
make dev.provision.discovery+registrar

Start over

If you want to completely start over, run make dev.destroy. This will remove all containers, networks, AND data volumes, requiring you to re-provision.

Troubleshooting: Common issues

File ownership change

If you notice that the ownership of some (maybe all) files have changed and you need to enter your root password when editing a file, you might have pulled changes to the remote repository from within a container. While running git pull, git changes the owner of the files that you pull to the user that runs that command. Within a container, that is the root user - so git operations should be ran outside of the container.

To fix this situation, change the owner back to yourself outside of the container by running:

$ sudo chown <user>:<group> -R .

Running LMS commands within a container

Most of the paver commands require a settings flag. If omitted, the flag defaults to devstack. If you run into issues running paver commands in a docker container, you should append the devstack_docker flag. For example:

$ paver update_assets --settings=devstack_docker

Resource busy or locked

While running make static within the ecommerce container you could get an error saying:

Error: Error: EBUSY: resource busy or locked, rmdir '/edx/app/ecommerce/ecommerce/ecommerce/static/build/'

To fix this, remove the directory manually outside of the container and run the command again.

No space left on device

If you see the error no space left on device, Docker has run out of space in its Docker.qcow2 file.

Here is an example error while running make dev.pull:

...
32d52c166025: Extracting [==================================================>] 1.598 GB/1.598 GB
ERROR: failed to register layer: Error processing tar file(exit status 1): write /edx/app/edxapp/edx-platform/.git/objects/pack/pack-4ff9873be2ca8ab77d4b0b302249676a37b3cd4b.pack: no space left on device
make: *** [pull] Error 1

Try this first to clean up dangling images:

docker system prune -f  # (This is very safe, so try this first.)

If you are still seeing issues, you can try cleaning up dangling volumes.

1. Bring up all containers.

make dev.up

2. Remove all unused volumes. Warning: this will remove all Docker data on your system that is not currently in use by a container, which is why it's important to run the previous step. Otherwise, this will wipe out your Devstack data.

   docker volume prune -f

No such file or directory

While provisioning, some have seen the following error:

...
cwd = os.getcwdu()
OSError: [Errno 2] No such file or directory
make: *** [dev.provision.services] Error 1

This issue can be worked around, but there's no guaranteed method to do so. Rebooting and restarting Docker does not seem to correct the issue. It may be an issue that is exacerbated by our use of sync (which typically speeds up the provisioning process on Mac), so you can try the following:

# repeat the following until you get past the error.
make stop
make dev.provision

Once you get past the issue, you should be able to continue to use sync versions of the make targets.

Memory Limit

While provisioning, some have seen the following error:

...
Build failed running pavelib.assets.update_assets: Subprocess return code: 137

This error is an indication that your docker process died during execution. Most likely, this error is due to running out of memory. Try increasing the memory allocated to Docker.

Docker is using lots of CPU time when it should be idle

On the Mac, this often manifests as the hyperkit process using a high percentage of available CPU resources. To identify the container(s) responsible for the CPU usage:

make dev.stats

Once you've identified a container using too much CPU time, check its logs; for example:

make dev.logs.lms

The most common culprit is an infinite restart loop where an error during service startup causes the process to exit, but we've configured docker-compose to immediately try starting it again (so the container will stay running long enough for you to use a shell to investigate and fix the problem). Make sure the set of packages installed in the container matches what your current code branch expects; you may need to rerun pip on a requirements file or pull new container images that already have the required package versions installed.

Troubleshooting: Performance

Improve Mac OSX Performance using nfs

The option to use docker with nfs on mac was added recently. This can potentially increase performance in mac osx. However, this option is still in testing phase. If you find any corrections that should be made, please start a PR with corrections.

Improve Mac OSX Performance with docker-sync

NOTE:

docker-sync is no longer actively supported. See section for nfs above for possible alternative.

Docker for Mac has known filesystem issues that significantly decrease performance for certain use cases, for example running tests in edx-platform. To improve performance, Docker Sync can be used to synchronize file data from the host machine to the containers.

Many developers have opted not to use Docker Sync because it adds complexity and can sometimes lead to issues with the filesystem getting out of sync.

You can swap between using Docker Sync and native volumes at any time, by using the make targets with or without 'sync'. However, this is harder to do quickly if you want to switch inside the PyCharm IDE due to its need to rebuild its cache of the containers' virtual environments.

If you are using macOS, please follow the Docker Sync installation instructions before provisioning.

Docker Sync Troubleshooting tips

Check your version and make sure you are running 0.4.6 or above:

docker-sync --version

If not, upgrade to the latest version:

gem update docker-sync

If you are having issues with docker sync, try the following:

make stop
docker-sync stop
docker-sync clean

Cached Consistency Mode

The performance improvements provided by cached consistency mode for volume mounts introduced in Docker CE Edge 17.04 are still not good enough. It's possible that the "delegated" consistency mode will be enough to no longer need docker-sync, but this feature hasn't been fully implemented yet (as of Docker 17.12.0-ce, "delegated" behaves the same as "cached"). There is a GitHub issue which explains the current status of implementing delegated consistency mode.

Advanced Configuration Options

The file options.mk sets several configuration options to default values. For example DEVSTACK_WORKSPACE (the folder where your Git repos are expected to be) is set to this directory's parent directory by default, and DEFAULT_SERVICES (the list of services that are provisioned and run by default) is set to a fairly long list of services out of the box. For more detail, refer to the comments in the file itself.

If you're feeling brave, you can create an git-ignored overrides file called options.local.mk in the same directory and set your own values. In general, it's good to bring down containers before changing any settings.