Ansible is a configuration management tool used to automate cloud provisioning and configuration management.

Prerequisites

Clone Milvus repository from GitHub to download the Ansible Milvus node deployment Playbook.

git clone https://github.com/milvus-io/milvus.git
Configure installation files
    
The inventory.ini and ansible.cfg files are used to control the environment variables and log-in verification methods in Ansible playbook. In the inventory.ini file, the dockernodes section defines all the servers of docker engines. The ansible.cfg section defines all the servers of Milvus coordinators. The node section defines all the servers of Milvus nodes.
Enter the local path to the Playbook and configure the installation files.
$ cd ./milvus/deployments/docker/cluster-distributed-deployment
inventory.ini
Configure inventory.ini to divide hosts in groups in accordance with their roles in the Milvus system.
Add host names, and define docker group and vars.
[dockernodes] #Add docker host names.
dockernode01
dockernode02
dockernode03
[admin] #Add Ansible controller name.
ansible-controller
[coords] #Add the host names of Milvus coordinators.
; Take note the IP of this host VM, and replace 10.170.0.17 with it.
dockernode01
[nodes] #Add the host names of Milvus nodes.
dockernode02
[dependencies] #Add the host names of Milvus dependencies.
; dependencies node will host etcd, minio, pulsar, these 3 roles are the foundation of Milvus. 
; Take note the IP of this host VM, and replace 10.170.0.19 with it.
dockernode03
[docker:children]
dockernodes
coords
nodes
dependencies
[docker:vars]
ansible_python_interpreter= /usr/bin/python3
StrictHostKeyChecking= no
; Setup variables to control what type of network to use when creating containers.
dependencies_network= host
nodes_network= host
; Setup varibale to control what version of Milvus image to use.
image= milvusdb/milvus-dev:master-20220412-4781db8a
; Setup static IP addresses of the docker hosts as variable for container environment variable config.
; Before running the playbook, below 4 IP addresses need to be replaced with the IP of your host VM
; on which the etcd, minio, pulsar, coordinators will be hosted.
etcd_ip= 10.170.0.19
minio_ip= 10.170.0.19
pulsar_ip= 10.170.0.19
coords_ip= 10.170.0.17
; Setup container environment which later will be used in container creation.
ETCD_ENDPOINTS= {{etcd_ip}}:2379 
MINIO_ADDRESS= {{minio_ip}}:9000
PULSAR_ADDRESS= pulsar://{{pulsar_ip}}:6650
QUERY_COORD_ADDRESS= {{coords_ip}}:19531
DATA_COORD_ADDRESS= {{coords_ip}}:13333
ROOT_COORD_ADDRESS= {{coords_ip}}:53100
INDEX_COORD_ADDRESS= {{coords_ip}}:31000
ansible.cfg
ansible.cfg controls the action of the playbook, for example, SSH key, etc. Do not set up passphrase via the SSH key on docker hosts. Otherwise, the Ansible SSH connection will fail. We recommend setting up the same username and SSH key on the three hosts and setting up the new user account to execute sudo without a password. Otherwise, you will receive errors that the user name does not match the password or you are not granted elevated privileges when running Ansible playbook.
[defaults]
host_key_checking = False
inventory = inventory.ini # Specify the Inventory file
private_key_file=~/.my_ssh_keys/gpc_sshkey # Specify the SSH key that Ansible uses to access Docker host
deploy-docker.yml
deploy-docker.yml defines the tasks during the installation of Docker. See the code comments in the file for details.
- name: setup pre-requisites # Install prerequisite
  hosts: all
  become: yes
  become_user: root
  roles:
    - install-modules
    - configure-hosts-file
- name: install docker
  become: yes
  become_user: root
  hosts: dockernodes
  roles:
    - docker-installation
Test Ansible connectivity
    
Test the connectivity to Ansible.
$ ansible all -m ping
Add -i in the command to specify the path to the inventory file if you did not specify it in ansible.cfg, otherwise Ansible uses /etc/ansible/hosts.
The terminal returns as follow:
dockernode01 | SUCCESS => {
"changed": false,
"ping": "pong"
ansible-controller | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    "changed": false,
    "ping": "pong"
dockernode03 | SUCCESS => {
    "changed": false,
    "ping": "pong"
dockernode02 | SUCCESS => {
    "changed": false,
    "ping": "pong"
Check the Playbook Syntax
    
Check the syntax of the Playbook.




    

$ ansible-playbook deploy-docker.yml --syntax-check
Normally, the terminal returns as follow:
playbook: deploy-docker.yml
Install Docker
    
Install Docker with the Playbook.
$ ansible-playbook deploy-docker.yml
If Docker is successfully installed on the three hosts, the terminal returns as follow:
TASK [docker-installation : Install Docker-CE] *******************************************************************
ok: [dockernode01]
ok: [dockernode03]
ok: [dockernode02]
TASK [docker-installation : Install python3-docker] **************************************************************
ok: [dockernode01]
ok: [dockernode02]
ok: [dockernode03]
TASK [docker-installation : Install docker-compose python3 library] **********************************************
changed: [dockernode01]
changed: [dockernode03]
changed: [dockernode02]
PLAY RECAP *******************************************************************************************************
ansible-controller         : ok=3    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
dockernode01               : ok=10   changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
dockernode02               : ok=10   changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
dockernode03               : ok=10   changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
Verify the installation
    
Log in to the three hosts with the SSH key, and verify the installation on the hosts.
For root host:
$ docker -v
For non-root hosts:
$ sudo docker -v
Normally, the terminal returns as follow:
Docker version 20.10.14, build a224086
Check the running status of the containers.
$ docker ps
Check the Syntax
    
Check the Syntax of deploy-milvus.yml.
$ ansible-playbook deploy-milvus.yml --syntax-check
Normally, the terminal returns as follow:
playbook: deploy-milvus.yml
Create Milvus container
    
The tasks to create Milvus container are defined in deploy-milvus.yml.
$ ansible-playbook deploy-milvus.yml
The terminal returns:
PLAY [Create milvus-etcd, minio, pulsar] *****************************************************************
TASK [Gathering Facts] ********************************************************************************************
ok: [dockernode03]
TASK [etcd] *******************************************************************************************************
changed: [dockernode03]
TASK [pulsar] *****************************************************************************************************
changed: [dockernode03]
TASK [minio] ******************************************************************************************************
changed: [dockernode03]
PLAY [Create milvus nodes] ****************************************************************************************
TASK [Gathering Facts] ********************************************************************************************
ok: [dockernode02]
TASK [querynode] **************************************************************************************************
changed: [dockernode02]
TASK [datanode] ***************************************************************************************************
changed: [dockernode02]
TASK [indexnode] **************************************************************************************************
changed: [dockernode02]
PLAY [Create milvus coords] ***************************************************************************************
TASK [Gathering Facts] ********************************************************************************************
ok: [dockernode01]
TASK [rootcoord] **************************************************************************************************
changed: [dockernode01]
TASK [datacoord] **************************************************************************************************
changed: [dockernode01]
TASK [querycoord] *************************************************************************************************
changed: [dockernode01]
TASK [indexcoord] *************************************************************************************************
changed: [dockernode01]
TASK [proxy] ******************************************************************************************************
changed: [dockernode01]
PLAY RECAP ********************************************************************************************************
dockernode01               : ok=6    changed=5    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
dockernode02               : ok=4    changed=3    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
dockernode03               : ok=4    changed=3    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
Now you have Milvus deployed on the three hosts.
Stop nodes
    
You can stop all nodes after you do not need a Milvus cluster any longer.
 Ensure that the terraform binary is available on your PATH. 
Run terraform destroy and enter yes when prompted.
If successful, all node instances are stopped.
What’s next
    
If you want to learn how to deploy Milvus on other clouds: