Remote Hosts

LoggiFly supports connecting to multiple remote hosts.
Remote hosts can be configured by providing a comma-separated list of addresses in the DOCKER_HOST environment variable.
To use TLS you have to mount /certs in the volumes section of your docker compose.
LoggiFly expects the TLS certificates to be in /certs/{ca,cert,key}.pem or in case of multiple hosts /certs/{host}/{ca,cert,key}.pem with {host} being either the IP or FQDN.

INFO

When the connection to a docker host is lost, LoggiFly will try to reconnect every 60s.

Labels

When multiple hosts are set LoggiFly will use labels to differentiate between them both in notifications and in logging.
You can set a label by appending it to the address with "|" (see example).
When no label is set LoggiFly will use the hostname retrieved via the docker daemon. If that fails, usually because INFO=1 has to be set when using a proxy, the labels will just be Host-{Nr}.
Note that labels and hostnames are only being used when there is more than one host being monitored.

TIP

If you want to set a label to your mounted docker socket you can do so by adding unix:///var/run/docker.sock|label in the DOCKER_HOST environment variable (the socket still has to be mounted) or just set the address of a socket proxy with a label.

Assign Containers to Hosts

Option 1: Assign containers to hosts via the hosts section

You can easily configure your containers in the config.yaml file under hosts.<your-hostname>. The labels section above shows how the hostname is constructed.

hosts:
  foo:
    containers:
      container1:
        keywords:
          - error
  bar:
    containers:
      container2:
        keywords:
          - critical
containers:
  container3:
    keywords:
      - timeout

In the above example container1 will only be monitored on host foo and container2 will only be monitored on host bar. container3 will be monitored on all hosts.

INFO

When a container is configured globally and on a specific host, the per-host configuration takes precedence.

Monitor all containers on specific hosts

The settings monitor_all_containers and excluded_containers also work per host

hosts:
  foo:
    monitor_all_containers: true
    excluded_containers:
      - container4
  bar:
    containers:
      container5:
        keywords:
          - error

Option 2: Assign containers to hosts via the hosts field of the container configuration

Another way to assign containers to specific hosts is by providing a comma-separated list of labels/hostnames in the hosts field of the container configuration.
When no hosts are set LoggiFly will look for the container on all configured remote hosts.

Here is a short yaml snippet:

containers:
  container1:
    hosts: foo,bar  # This container will only be monitored on hosts with the labels 'foo' and 'bar'
    keywords:
      - error

Remote Hosts Example

In this example, LoggiFly monitors container logs from the local host via a mounted Docker socket, as well as from two remote Docker hosts configured with TLS. One of the remote hosts is referred to as ‘foobar’. The local host and the second remote host have no custom label and are identified by their respective hostnames.

version: "3.8"
services:
  loggifly:
    image: ghcr.io/clemcer/loggifly:latest
    container_name: loggifly 
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock:ro
      - ./loggifly/config:/config # Place your config.yaml here if you are using one
      - ./certs:/certs
      # Assuming the Docker hosts use TLS, the folder structure for the certificates should be like this:
      # /certs/
      # ├── 192.168.178.80/
      # │   ├── ca.pem
      # │   ├── cert.pem
      # │   └── key.pem
      # └── 192.168.178.81/
      #     ├── ca.pem
      #     ├── cert.pem
      #     └── key.pem
    environment:
      TZ: Europe/Berlin
      DOCKER_HOST: tcp://192.168.178.80:2376,tcp://192.168.178.81:2376|foobar
    restart: unless-stopped

Socket Proxy

The simplest way to use LoggiFly with remote hosts is to use a docker socket proxy. Just take a look at the docker compose examples and set up the socket proxy on your remote host.

INFO

Container restart/stop actions are not supported when using a Docker Socket Proxy unless you use the compose example with tecnativa/docker-socket-proxy and POST=1 is enabled.