_____ __       ____
  / ___// /____  / / /___ ______
  \__ \/ __/ _ \/ / / __ `/ ___/
 ___/ / /_/  __/ / / /_/ / /
/____/\__/\___/_/_/\__,_/_/

Simplified Container Runtime Cluster

Stellar is designed to provide simple container runtime clustering. One or more nodes are joined together to create a cluster. The cluster is eventually consistent making it ideal for transient workloads or edge computing where nodes are not always guaranteed to have high bandwidth, low latency connectivity.

Why

There are several container platforms and container orchestrators out there. However, they are too complex for my use. I like simple infrastructure that is easy to deploy and manage, tolerates failure cases and is easy to debug when needed. With the increased tolerance in failure modes, this comes at a consistency cost. It may not be for you. Use the best tool for your use case. Enjoy :)

Features

• Container execution via containerd
• Multihost Networking via CNI
• Service Discovery via DNS
• Cluster event system via NATS
• Builtin Proxy using Radiant (zero downtime reloads, canary deploys, health checks, automatic HTTPS)
• Masterless design
• Efficient use of system resources
• Simple daemon deployment

Downloads

For official releases, see the Releases

You can also grab the latest Master Build

Building

In order to build Stellar you will need the following:

• A working Go environment (1.11+)
• Protoc 3.x compiler and headers (download at the Google releases page)

Once you have the requirements you can build.

If you change / update the protobuf definitions you will need to generate:

make generate

To build the binaries (client and server) run:

make

Docker

Alternatively you can use Docker to build:

To generate protobuf:

make docker-generate

To build binaries:

make docker-build

Running

To run Stellar, once you have a working containerd installation follow these steps:

• Install Containerd
• Build binaries or get a release
• Copy /bin/sctl to /usr/local/bin/
• Copy /bin/stellar to /usr/local/bin/
• Copy /bin/stellar-cni-ipam to /opt/containerd/bin/ or /opt/cni/bin

First, we will generate a config:

$> stellar config > stellar.conf

This will produce a default configuration. Edit the addresses to match your environment. For this example we will use the IP 10.0.1.70.

{
    "ConnectionType": "local",
    "ClusterAddress": "10.0.1.70:7946",
    "AdvertiseAddress": "10.0.1.70:7946",
    "Debug": false,
    "NodeID": "dev",
    "GRPCAddress": "10.0.1.70:9000",
    "TLSServerCertificate": "",
    "TLSServerKey": "",
    "TLSClientCertificate": "",
    "TLSClientKey": "",
    "TLSInsecureSkipVerify": false,
    "ContainerdAddr": "/run/containerd/containerd.sock",
    "Namespace": "default",
    "DataDir": "/var/lib/stellar",
    "StateDir": "/run/stellar",
    "Bridge": "stellar0",
    "UpstreamDNSAddr": "8.8.8.8:53",
    "ProxyHTTPPort": 80,
    "ProxyHTTPSPort": 443,
    "ProxyTLSEmail": "",
    "GatewayAddress": "127.0.0.1:9001",
    "EventsAddress": "10.0.1.70:4222",
    "EventsClusterAddress": "10.0.1.70:5222",
    "EventsHTTPAddress": "10.0.1.70:4322",
    "CNIBinPaths": [
        "/opt/containerd/bin",
        "/opt/cni/bin"
    ],
    "Peers": [],
    "Subnet": "172.16.0.0/12"
}

To start the initial node run:

$> stellar -D server --config stellar.conf

To join additional nodes simply add the AdvertiseAddress of the first node to the Peers config option of the second node:

For example:

{
    "ConnectionType": "local",
    "ClusterAddress": "10.0.1.71:7946",
    "AdvertiseAddress": "10.0.1.71:7946",
    "Debug": false,
    "NodeID": "dev",
    "GRPCAddress": "10.0.1.71:9000",
    "TLSServerCertificate": "",
    "TLSServerKey": "",
    "TLSClientCertificate": "",
    "TLSClientKey": "",
    "TLSInsecureSkipVerify": false,
    "ContainerdAddr": "/run/containerd/containerd.sock",
    "Namespace": "default",
    "DataDir": "/var/lib/stellar",
    "StateDir": "/run/stellar",
    "Bridge": "stellar0",
    "UpstreamDNSAddr": "8.8.8.8:53",
    "ProxyHTTPPort": 80,
    "ProxyHTTPSPort": 443,
    "ProxyTLSEmail": "",
    "GatewayAddress": "127.0.0.1:9001",
    "EventsAddress": "10.0.1.71:4222",
    "EventsClusterAddress": "10.0.1.71:5222",
    "EventsHTTPAddress": "10.0.1.71:4322",
    "CNIBinPaths": [
        "/opt/containerd/bin",
        "/opt/cni/bin"
    ],
    "Peers": ["10.0.1.70:7946"],
    "Subnet": "172.16.0.0/12"
}

You will now have a two node cluster. To see node information, use sctl.

$> sctl --addr 10.0.1.70:9000 cluster nodes
NAME                ADDR                OS                       UPTIME              CPUS                MEMORY (USED)
stellar-00          10.0.1.70:9000      Linux (4.17.0-3-amd64)   7 seconds           2                   242 MB / 2.1 GB
stellar-01          10.0.1.71:9000      Linux (4.17.0-3-amd64)   6 seconds           2                   246 MB / 2.1 GB

Deploying an Application

To deploy an application, create an application config. For example, create the following as example.conf:

{
    "name": "example",
    "labels": [
        "env=prod",
        "region=us-east"
    ],
    "services": [
        {
            "name": "redis",
            "image": "docker.io/library/redis:alpine",
            "runtime": "io.containerd.runtime.v1.linux",
            "process": {
                "uid": 0,
                "gid": 0,
                "args": ["redis-server"]
            },
            "labels": [
                "env=prod"
            ],
            "network": true
        }
    ]
}

Then run the following to deploy:

$> sctl --addr 10.0.1.70:9000 apps create -f ./example.conf

You should now see the application deployed:

$> sctl --addr 10.0.1.70:9000 apps list
NAME                SERVICES
example             1

$> sctl --addr 10.0.1.70:9000 apps inspect example
Name: example
Services:
  - Name: example.redis
    Image: docker.io/library/redis:alpine
    Runtime: io.containerd.runtime.v1.linux
    Snapshotter: overlayfs
    Labels:
      containerd.io/restart.status=running
      stellar.io/application=example
      stellar.io/network=true

By default all applications that have networking enabled will have a corresponding nameserver record created. To view the records use the following:

$> sctl --addr 10.0.1.70:9000 nameserver list
NAME                    TYPE                VALUE                                            OPTIONS
example.redis.stellar   A                   172.16.0.4
example.redis.stellar   TXT                 node=stellar-00; updated=2018-09-08T10:71:02-04:00