shanejonas / deis

Your PaaS. Your Rules.

Deis

Deis (pronounced DAY-iss) is an open source PaaS that makes it easy to deploy and manage applications on your own servers. Deis builds upon Docker and CoreOS to provide a lightweight PaaS with a Heroku-inspired workflow.

New Deis

Deis has undergone several improvements recently. If you are updating from Deis version 0.7.0 or earlier, there are several big changes you should know about. Read the MIGRATING.md document for details.

If you need to use Deis with Chef integration, on Ubuntu 12.04 LTS, or on DigitalOcean, you should use the v0.7.0 release of Deis.

Deploying Deis

Deis is a set of Docker containers that can be deployed anywhere including public cloud, private cloud, bare metal or your workstation. Decide where you'd like to deploy Deis, then follow the deployment-specific documentation for Rackspace, EC2, or bare-metal provisioning. Documentation for other platforms is forthcoming. Want to see a particular platform supported? Open an issue and we'll investigate.

Trying out Deis? Continue following these instructions for a local cluster setup. This is also a great Deis testing/development environment.

Install prerequisites

On your workstation:

• Install Vagrant and VirtualBox
• Install the fleetctl client: Install v0.3.2 from the fleet GitHub page.
• Install the Docker client if you want to run Docker commands locally (optional)

If you're on Ubuntu, you need to install the nfs-kernel-server package as it's required for sharing folders between your host and your CoreOS VM:

sudo apt-get install nfs-kernel-server

Additional setup for a multi-node cluster

If you'd like to spin up more than one VM to test an entire cluster, there are a few additional prerequisites:

• Edit contrib/coreos/user-data and add a unique discovery URL generated from https://discovery.etcd.io/new
• Set DEIS_NUM_INSTANCES to the desired size of your cluster (typically 3 or 5): $ export DEIS_NUM_INSTANCES=3
• Instead of local.deisapp.com, use either local3.deisapp.com or local5.deisapp.com as your hostname for accessing the cluster

Note that for scheduling to work properly, clusters must consist of at least 3 nodes and always have an odd number of members. For more information, see optimal etcd cluster size.

Deis clusters of less than 3 nodes are unsupported for anything other than local development.

Boot CoreOS

First, start the CoreOS cluster on VirtualBox. From a command prompt, cd to the root of the Deis project code and type:

$ vagrant up

This instructs Vagrant to spin up each VM. To be able to connect to the VMs, you must add your Vagrant-generated SSH key to the ssh-agent (fleetctl tunnel requires the agent to have this key):

$ ssh-add ~/.vagrant.d/insecure_private_key

Export some environment variables so you can connect to the VM using the docker and fleetctl clients on your workstation.

$ export DOCKER_HOST=tcp://172.17.8.100:4243
$ export FLEETCTL_TUNNEL=172.17.8.100

Build Deis

Use make pull to download cached layers from the public Docker Index. Then use make build to assemble all of the Deis components from Dockerfiles. Grab some coffee while it builds the images on each VM (it can take a while).

$ make pull
$ make build

Run Deis

Use make run to start all Deis containers and attach to their log output. This can take some time - the registry service will pull and prepare a Docker image. Grab some more coffee!

$ make run

Your Vagrant VM is accessible at local.deisapp.com (or local3.deisapp.com/local5.deisapp.com). For clusters on other platforms (EC2, Rackspace, bare metal, etc.), see our guide to Configuring DNS.

Testing the cluster

Integration tests and corresponding documentation can be found under the test/ folder.

These systemd services run the various containers which compose Deis, and can be stopped on a machine with sudo systemctl stop servicename.

• deis-builder.service
• deis-cache.service
• deis-controller.service
• deis-database.service
• deis-discovery.service
• deis-logger.service
• deis-registry.service
• deis-router.service

Logging into one of the CoreOS machines and stopping a container service should cause the same component on another CoreOS host to take over as master. Similarly, bringing down a VM should enable the services on another VM to take over as master.

Install the Deis Client

If you're using the latest Deis release, use pip install deis to install the latest Deis Client or download pre-compiled binaries.

If you're working off master, precompiled binaries are likely out of date. You should either symlink the python file directly or build a local copy of the client:

$ ln -fs $(pwd)/client/deis.py /usr/local/bin/deis

or

$ cd client && python setup.py install

Register a User

Use the Deis Client to register a new user.

$ deis register http://local.deisapp.com:8000
$ deis keys:add

Use deis keys:add to add your SSH public key for git push access.

Initialize a Cluster

Initialize a dev cluster with a list of CoreOS hosts and your CoreOS private key.

$ deis clusters:create dev local.deisapp.com --hosts=local.deisapp.com --auth=~/.vagrant.d/insecure_private_key

The parameters to deis clusters:create are:

• cluster name (dev) - the name used by Deis to reference the cluster
• cluster hostname (local.deisapp.com) - the hostname under which apps are created, like balancing-giraffe.local.deisapp.com
• cluster members (--hosts) - a comma-separated list of cluster members -- not necessarily all members, but at least one (for EC2 and Rackspace, this is a list of the internal IPs like --hosts=10.21.12.1,10.21.12.2,10.21.12.3)
• auth SSH key (--auth) - the SSH private key used to provision servers (for EC2 and Rackspace, this key is likely ~/.ssh/deis)

The dev cluster will be used as the default cluster for future deis commands.

Usage

Create an Application

Create an application on the default dev cluster.

$ deis create

Use deis create --cluster=prod to place the app on a different cluster. Don't like our name-generator? Use deis create myappname.

Push

Push builds of your application from your local git repository or from a Docker Registry. Each build creates a new release, which can be rolled back.

From a Git Repository

When you created the application, a git remote for Deis was added automatically.

$ git push deis master

This will use the Deis builder to package your application as a Docker Image and deploy it on your application's cluster.

Configure

Configure your application with environment variables. Each config change also creates a new release.

$ deis config:set DATABASE_URL=postgres://

Coming soon: Use the integrated ETCD namespace for service discovery between applications on the same cluster.

Test

Run tests

Test your application by running commands inside an ephemeral Docker container.

$ deis run make test

To integrate with your CI system, check the return code.

Scale

Scale containers horizontally with ease.

$ deis scale web=8

Debug

Access to aggregated logs makes it easy to troubleshoot problems with your application.

$ deis logs

Use deis run to execute one-off commands and explore the deployed container. Coming soon: deis attach to jump into a live container.

Known Issues

We have sometimes seen the VM reboot while doing make build against a Vagrant virtual machine. If you see this issue using a recent version of Vagrant and the current master version of Deis, please add to the issue report at https://github.com/coreos/coreos-vagrant/issues/68 to help us pin it down.

Troubleshooting

Common issues that users have run into when provisioning Deis are detailed below.

When running a make action - 'Failed initializing SSH client: ssh: handshake failed: ssh: unable to authenticate'

Did you remember to add your SSH key to the ssh-agent? ssh-agent -L should list the key you used to provision the servers. If it's not there, ssh-add -K /path/to/your/key.

When running a make action - 'All the given peers are not reachable (Tried to connect to each peer twice and failed)'

The most common cause of this issue is that a new discovery URL wasn't generated and updated in contrib/coreos/user-data before the cluster was launched. Each Deis cluster must have a unique discovery URL, else there will be entries for old hosts that etcd will try and fail to connect to. Destroy and relaunch the cluster, ensuring to use a fresh discovery URL.

Various NFS issues, specifically an 'access denied' error

The easiest workaround for this is to use rsync instead of NFS. In the Vagrantfile, swap out the config.vm.synced_folder line for the commented version.

Scaling an app doesn't work, and/or the app shows 'Welcome to nginx!'

This means the controller failed to submit jobs for the app to fleet. fleetctl status deis-controller will show detailed error information, but the most common cause of this is that the cluster was created with the wrong SSH key for the --auth parameter. The key supplied with the --auth parameter must be the same key that was used to provision the Deis servers. If you suspect this to be the issue, you'll need to clusters:destroy the cluster and recreate it, along with the app.

A Deis component fails to start

Use fleetctl status deis-<component>.service to get the output of the service. The most common cause of services failing to start are sporadic issues with the Docker index. The telltale sign of this is:

May 12 18:24:37 deis-3 systemd[1]: Starting deis-controller...
May 12 18:24:37 deis-3 sh[6176]: 2014/05/12 18:24:37 Error: No such id: deis/controller
May 12 18:24:37 deis-3 sh[6176]: Pulling repository deis/controller
May 12 18:29:47 deis-3 sh[6176]: 2014/05/12 18:29:47 Could not find repository on any of the indexed registries.
May 12 18:29:47 deis-3 systemd[1]: deis-controller.service: control process exited, code=exited status=1
May 12 18:29:47 deis-3 systemd[1]: Failed to start deis-controller.
May 12 18:29:47 deis-3 systemd[1]: Unit deis-controller.service entered failed state.

We are exploring workarounds and are working with the Docker team to improve their index. In the meantime, try starting the service again with fleetctl start deis-<component>.service.

Any other issues

Running into something not detailed here? Please open an issue or hop into #deis and we'll help!

License

Copyright 2014, OpDemand LLC

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.