Flynn is a next generation open source Platform as a Service (PaaS).
Unlike most PaaS's, Flynn can run stateful services as well as twelve-factor apps. This includes built-in database appliances (just Postgres to start). Flynn is modular so users can easily modify, upgrade, and replace components.
Flynn components are divided into two layers.
Layer 1 is a set of higher level components that makes it easy to deploy and maintain applications and databases.
You can learn more about the project at the Flynn website.
Flynn is in active development and currently unsuitable for production use.
Users are encouraged to experiment with Flynn but should assume there are stability, security, and performance weaknesses throughout the project. This warning will be removed when Flynn is ready for production use.
Please report bugs as issues on this repository after searching to see if anyone has already reported the issue.
We have a web dashboard for launching Flynn clusters on your Amazon Web Services account.
You can also download a demo environment for your local machine or learn about the components below.
Trying it out
With a Flynn cluster running and the
flynn tool installed and configured, the
first thing you'll want to do is add your SSH key so that you can deploy
flynn key add
After adding your ssh key, you can deploy a new application:
git clone https://github.com/flynn/nodejs-flynn-example cd nodejs-flynn-example flynn create example git push flynn master
By default there will be one process running, add some more web processes using
flynn scale web=3
Visit the application in your browser or with curl:
Repeated requests should show that the requests are load balanced across the running processes.
flynn ps will show the running processes:
$ flynn ps ID TYPE e4cffae4ce2b-8cb1212f582f498eaed467fede768d6f web e4cffae4ce2b-da9c86b1e9e743f2acd5793b151dcf99 web e4cffae4ce2b-1b17dd7be8e44ca1a76259a7bca244e1 web
To get the log from a process, use
$ flynn log e4cffae4ce2b-8cb1212f582f498eaed467fede768d6f Listening on 55007
An interactive one-off process may be spawned in a container:
flynn run bash
Manual Ubuntu Deployment
Currently only Ubuntu 14.04 amd64 is supported for manual installation, but this is a temporary packaging limitation, we have no actual dependency on Ubuntu.
If you plan to run a multi-node cluster, you should boot at least 3 nodes to keep etcd efficient (see here for an explanation).
The first step is to install the
flynn-host package and container images:
apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv BC79739C507A9B53BB1B0E7D820A5489998D827B echo deb https://dl.flynn.io/ubuntu flynn main > /etc/apt/sources.list.d/flynn.list apt-get update apt-get install -y linux-image-extra-$(uname -r) flynn-host flynn-release download /etc/flynn/version.json
Do this on every host that you want to be in the Flynn cluster.
The ports 80, 443, and 2222 must be open externally on the firewalls for all nodes in the cluster, and the nodes need to be able to communicate with each other internally on all ports.
The next step is to configure a Layer 0 cluster. The host daemon finds other members of the cluster using the etcd, which needs to be bootstrapped.
Note: a new token must be used every time you restart all nodes in the cluster.
Then, start the daemon by running
After you have a running Layer 0 cluster, bootstrap Layer 1 with
flynn-bootstrap. You'll need a domain name with DNS A records pointing to
every node IP address and a second, wildcard domain CNAME to the cluster domain.
demo.localflynn.com. A 192.168.84.42 *.demo.localflynn.com. CNAME demo.localflynn.com.
DEFAULT_ROUTE_DOMAIN should be set to the two
CONTROLLER_DOMAIN=demo.localflynn.com \ DEFAULT_ROUTE_DOMAIN=demo.localflynn.com \ flynn-bootstrap /etc/flynn/bootstrap-manifest.json
The Layer 1 bootstrapper will get all necessary services running using the Layer 0 API. The final log line will contain configuration that may be used with the command-line interface.
If you try these instructions and run into issues, please open an issue or pull request.
host The Flynn host service, manages containers on each host and provides the scheduling framework.
discoverd The Flynn service discovery system.
bootstrap Bootstraps Flynn Layer 1 from a JSON manifest using the Layer 0 API.
controller Provides management and scheduling of applications running on Flynn via an HTTP API.
gitreceived An SSH server made specifically for accepting git pushes.
cli Command-line Flynn HTTP API client.
receiver Flynn's git deployer.
router Flynn's TCP/HTTP router/load balancer.
blobstore A simple, fast HTTP file service.
taffy Taffy pulls git repos and deploys them to Flynn.
We welcome and encourage community contributions to Flynn.
Since the project is still unstable, there are specific priorities for development. Pull requests that do not address these priorities will not be accepted until Flynn is production ready.
There are many ways to help Flynn besides contributing code:
- Find bugs and file issues.
- Improve the documentation and website.
Learn more at flynn.io.
Flynn is a trademark of Prime Directive, Inc.