如何从master获取minion的主机名

Question

I am using salt stack. From the master (node01), I am using cmd.run to run docker-compose task on minions (node02).

My docker-compose file needs to know the hostname of minion node02 but currently since the task is being run from master node01 , the docker-compose file receives the hostname of the master and not the minion.

node01 and node02 are on the same network

Salt command run on node01

 salt-cp -L node02 docker-compose.yml /my/path
 salt -L node02 cmd.run "docker-compose -f /my/path/docker-compose.yml pull &&
 docker-compose -f /my/path/docker-compose.yml down && 
 docker-compose -f /my/path/docker-compose.yml up -d" --timeout=600

In the following example Docker Compose file, I would like to pass the HOST_NAME to the command. Right now, I have to create multiple different docker-compose files for each node as passing the hostname isn't working

version: "3.3"
# interaction
services:
  consul:
    command: -node=HOST_NAME --join=192.168.0.30 --advertise=192.168.0.30
    image: progrium/consul:latest
    hostname: "consul"
    container_name: consul
    ports:
    - "8300:8300"
    - "8400:8400"
    - "8500:8500"
    - "8600:53/udp"
    - "8301:8301"
    - "8302:8302"
    network_mode: "host"
    restart: always

In my current setup, how do I pass the hostname of the minion to docker-compose when running the command from the master?

Answer 1

If you're using a recipe it could be achieve easily with some jinja in your docker compose file:

in your docker-compose.yml you will have this:

version: "3.3"
# interaction
services:
  consul:
    command: -node={{ pillar['docker_hostname'] }} --join=192.168.0.30 --advertise=192.168.0.30
    image: progrium/consul:latest
    hostname: "consul"
    container_name: consul
    ports:
    - "8300:8300"
    - "8400:8400"
    - "8500:8500"
    - "8600:53/udp"
    - "8301:8301"
    - "8302:8302"
    network_mode: "host"
    restart: always

When doing a file.managed from the master to the minion, the jinja part will be replaced.

You will have to put this file in the /srv/salt hierarchy. lets say /srv/salt/files/docker-compose.yml

then in /srv/salt/docker.sls:

copy docker-compose:
  file.managed:
    - name: '/my/path/docker-compose.yml'
    - source: salt://files/docker-compose.yml.jinja
    - template: jinja

run docker:
  cmd.run:
    - name: "docker-compose -f /my/path/docker-compose.yml pull && docker-compose -f /my/path/docker-compose.yml down && docker-compose -f /my/path/docker-compose.yml up -d"

And after you juste have to use your recipe and to pass as a parameter the hostname (test in my example)

salt 'node2' state.sls docker pillar='{"docker_hostname": "test"}'