deis

README

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.

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, DigitalOcean, Google Compute Engine 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.

Upgrading Deis

Upgrading from a previous Deis release? See Upgrading Deis for additional information.

Deis is pre-release software. The current release is v0.11.0. Until there is a stable release, we recommend you check out the latest "master" branch code and refer to the latest documentation.

Install prerequisites

On your workstation:

• Install Vagrant v1.6+ and VirtualBox
• Install the fleetctl client: Install v0.6.2 from the fleet GitHub page.

A single-node cluster launched with Vagrant will consume about 5 GB of RAM on the host machine. Please be sure you have sufficient free memory before proceeding.

Note for Ubuntu users: the VirtualBox package in Ubuntu (as of the last known release for 14.04) has some issues when running in RAM-constrained environments. Please install the lastest version of VirtualBox from Oracle's website.

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
• If you'd like to spin up more than one router, set DEIS_NUM_ROUTERS: $ export DEIS_NUM_ROUTERS=2
• Instead of local.deisapp.com, use either local3.deisapp.com or local5.deisapp.com as your cluster domain

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 FLEETCTL_TUNNEL so you can connect to the VM using the fleetctl client on your workstation.

$ export FLEETCTL_TUNNEL=172.17.8.100

Optional: Build Deis

If you'd like to build Deis from source instead of using the pre-built public Dockerfiles, use make build to build each component from its Dockerfile. Grab some coffee while it builds the images on each VM (it can take a while). If you're not testing code changes for Deis, it's faster just to skip to the next step.

$ make build

Run Deis

Use make run to start all Deis components. This can take some time - the registry service will pull and prepare a large 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, DigitalOcean, bare metal, etc.), see our guide to Configuring DNS.

Testing the cluster

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

Install the Deis Client

If you're using the latest Deis release, use pip install --upgrade 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://deis.local.deisapp.com
$ 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=172.17.8.100 --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 cloud providers, this is a list of the 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 -- cannot have a password (for cloud providers, this key is likely ~/.ssh/deis)

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

Usage

Clone an example application or use an existing one

Example applications can be cloned from the Deis GitHub organization. Commonly-used example applications include Helloworld (Dockerfile), Go, and Ruby.

Create an Application

From within the application directory, create an application on the default dev cluster:

$ cd example-ruby-sinatra
$ 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://

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.

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.

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.