A docker container autorestart tool.
When using docker-compose with the network_mode: "service:parent_name" option or docker with the --net:container:parent_name, the attached container will permanantly lose its network connection if the parent container restarts.
This mode enables using the network stack of another container (eg: for tunneling traffic through a VPN), but this inability to restart children makes it less useful in scenarios where the parent container sometimes restarts.
There have been issues raised about this for many years on the Docker github, but they were not resolved:
Dependheal will listen to the docker daemon to know when a container starts or stops.
Containers must have the dependheal.enable=true label for Dependheal to listen for them.
Alternatively, Dependheal will listen to all containers if the environment variable DEPENDHEAL_ENABLE_ALL=true.
Dependheal will connect containers to networks if the dependheal.networks label exists on the container.
This label accepts a comma delimited list of networks, i.e. dependheal.networks = network1, network2.
Any container with the dependheal.parent=<parent_name> label will be restarted automatically if the <parent_name> container restarts.
If the dependheal.wait_for_parent_healthy=true label is set, the container will be restarted once the parent container's healthcheck passes. Otherwise Dependheal will immediately restart it.
Dependheal will also automatically restart containers that have failing healthchecks. To add a timeout between a container going unhealthy and Dependheal restarting it, add this label dependheal.timeout=<timeout> where <timeout> is either an integer or a floating point number. Otherwise Dependheal will immediately restart it.
By default, dependheal will log messages at the info level. To get debug logging, pass the environment variable DEBUG=true.
Run go mod download to download dependencies.
Run go build to build the dependheal executable.
Run the executable with ./dependheal
Run docker build -t dependheal . to build the docker image.
Run docker run -d --name dependheal --restart=unless-stopped -v /var/run/docker.sock:/var/run/docker.sock dependheal:latest to start the docker image.
version: "3.9"
services:
dependheal:
container_name: dependheal
image: dependheal:latest
restart: unless-stopped
volumes:
- /var/run/docker.sock:/var/run/docker.sock
parent_container:
container_name: parent_container
image: parent:latest
restart: unless-stopped
labels:
- "dependheal.enable=true"
child_container:
container_name: child_container
image: child:latest
depends_on:
- parent_container
network_mode: service:parent_container
labels:
- "dependheal.enable=true"
- "dependheal.parent=parent_container"