woodpecker/docs/setup/docker.md
2015-10-07 17:17:15 -07:00

2.9 KiB

Docker

Drone uses the local Docker daemon (at unix:///var/run/docker.sock) to execute your builds with 2x concurrency. This section describes how to customize your Docker configuration and concurrency settings using the DOCKER_* environment variables.

Configure a single Docker host (1x build concurrency):

DOCKER_HOST="unix:///var/run/docker.sock"

Concurrency

Configure Drone to run multiple, concurrent builds by increasing the number of registered Docker hosts. Each DOCKER_HOST_* environment variable will increase concurrency by 1.

Configure multiple Docker hosts (4x build concurrency):

DOCKER_HOST_1="unix:///var/run/docker.sock"
DOCKER_HOST_2="unix:///var/run/docker.sock"
DOCKER_HOST_3="unix:///var/run/docker.sock"
DOCKER_HOST_4="unix:///var/run/docker.sock"

Configure a single, external Docker host (1x build concurrency):

DOCKER_HOST="tcp://1.2.3.4:2376"

DOCKER_CA="/path/to/ca.pem"
DOCKER_CERT="/path/to/cert.pem"
DOCKER_KEY="/path/to/key.pem"

Configure multiple, external Docker hosts (4x build concurrency using 2 remote servers):

DOCKER_HOST_1="tcp://1.2.3.4:2376"
DOCKER_HOST_2="tcp://1.2.3.4:2376"

DOCKER_HOST_3="tcp://4.3.2.1:2376"
DOCKER_HOST_4="tcp://4.3.2.1:2376"

DOCKER_CA="/path/to/ca.pem"
DOCKER_CERT="/path/to/cert.pem"
DOCKER_KEY="/path/to/key.pem"

Remote Servers

Connecting to remote Docker servers requires TLS authentication for security reasons. You will therefore need to generate your own self-signed certificates. For convenience, we've created the following gist to help generate a certificate: https://gist.github.com/bradrydzewski/a6090115b3fecfc25280

This will generate the following files:

  • ca.pem
  • cert.pem
  • key.pem
  • server-cert.pem
  • server-key.pem

Tell Drone where to find the cert.pem and key.pem:

DOCKER_CERT="/path/to/cert.pem"
DOCKER_KEY="/path/to/key.pem"

When running Drone inside Docker, you'll need to mount the volume containing the certificate:

docker run
    --volume /path/to/cert.pem:/path/to/cert.pem \
    --volume /path/to/key.pem:/path/to/key.pem   \

Tell Docker where to find the certificate files. Install the certificates on every remote machine (in /etc/ssl/docker/) and update each Docker configuration file (at /etc/init/drone-dart.conf) accordingly:

# Use DOCKER_OPTS to modify the daemon startup options.
DOCKER_OPTS="--tlsverify --tlscacert=/etc/ssl/docker/ca.pem --tlscert=/etc/ssl/docker/server-cert.pem --tlskey=/etc/ssl/docker/server-key.pem -H=0.0.0.0:2376 -H unix:///var/run/docker.sock"

Verify that everything is configured correctly by connecting to a remote Docker server from our Drone server using the following command:

sudo docker                     \
    --tls                       \
    --tlscacert=/path/to/ca.pem \
    --tlscert=/path/to/cert.pem \
    --tlskey=/path/to/key.pem   \
    -H="1.2.3.4:2376" version