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Finally, after all the configuration stuff is done, we can run the playbooks

Create SSH Access

First the SSH Access on all nodes need to be created. Therefore the access-onprem.yml is used:
Be careful, I used CentOS on my system, so I commented the apt-get and the debian-based part out.
If you want to run the playbook on another operating system, adjust it carefully.

---
# This playbook enable access to all ansible targets via ssh

- name: setup the ansible requirements on all nodes
  hosts: all:!localhost
  #hosts: all
  serial: 20
  remote_user: "{{ initial_remote_user | default('root') }}"
  become: true
  tasks:

#    - name: attempt to update apt's cache
#      raw: test -e /usr/bin/apt-get && apt-get update
#      ignore_errors: yes

#    - name: attempt to install Python on Debian-based systems
#      raw: test -e /usr/bin/apt-get && apt-get -y install python-simplejson python
#      ignore_errors: yes

    - name: attempt to install Python on CentOS-based systems
      raw: test -e /usr/bin/yum && yum -y install python-simplejson python
      ignore_errors: yes

    - name: Create admin user group
      group:
        name: admin
        system: yes
        state: present

    - name: Ensure sudo is installed
      package:
        name: sudo
        state: present

    - name: Remove user centos
      user:
        name: centos
        state: absent
        remove: yes

    - name: Create Ansible user
      user:
        name: "{{ lookup('ini', 'remote_user section=defaults file=../ansible.cfg') }}"
        shell: /bin/bash
        comment: "Ansible management user"
        home: "/home/{{ lookup('ini', 'remote_user section=defaults file=../ansible.cfg') }}"
        createhome: yes
        password: "admin123"

    - name: Add Ansible user to admin group
      user:
        name: "{{ lookup('ini', 'remote_user section=defaults file=../ansible.cfg') }}"
        groups: admin
        append: yes

    - name: Add authorized key
      authorized_key:
        user: "{{ lookup('ini', 'remote_user section=defaults file=../ansible.cfg') }}"
        state: present
        key: "{{ lookup('file', lookup('env','HOME') + '/.ssh/ansible-dcos.pub') }}"

    - name: Copy sudoers file
      command: cp -f /etc/sudoers /etc/sudoers.tmp

    - name: Backup sudoers file
      command: cp -f /etc/sudoers /etc/sudoers.bak

    - name: Ensure admin group can sudo
      lineinfile:
        dest: /etc/sudoers.tmp
        state: present
        regexp: '^%admin'
        line: '%admin ALL=(ALL) NOPASSWD: ALL'
      when: ansible_os_family == 'Debian'

    - name: Ensure admin group can sudo
      lineinfile:
        dest: /etc/sudoers.tmp
        state: present
        regexp: '^%admin'
        insertafter: '^root'
        line: '%admin ALL=(ALL) NOPASSWD: ALL'
      when: ansible_os_family == 'RedHat'

    - name: Replace sudoers file
      shell: visudo -q -c -f /etc/sudoers.tmp && cp -f /etc/sudoers.tmp /etc/sudoers

    - name: Test Ansible user's access
      local_action: "shell ssh {{ lookup('ini', 'remote_user section=defaults file=../ansible.cfg') }}@{{ ansible_host }} 'sudo echo success'"
      become: False
      register: ansible_success

    - name: Remove Ansible SSH key from bootstrap user's authorized keys
      lineinfile:
        path: "{{ ansible_env.HOME }}/.ssh/authorized_keys"
        state: absent
        regexp: '^ssh-rsa AAAAB3N'
      when: ansible_success.stdout == "success"

Start the Playbook for the SSH access

[root@dcos-ansible ansible-dcos]# pwd
/root/ansible-dcos

[root@dcos-ansible ansible-dcos]# ansible-playbook plays/access-onprem.yml
PLAY [setup the ansible requirements on all nodes] 
****************************************************************************************
TASK [Gathering Facts]
****************************************************************************************
ok: [192.168.22.103]
ok: [192.168.22.102]
ok: [192.168.22.104]
ok: [192.168.22.101]
ok: [192.168.22.100]

[....]

PLAY RECAP 
**************************************************************************************
192.168.22.100             : ok=14   changed=6    unreachable=0    failed=0
192.168.22.101             : ok=14   changed=6    unreachable=0    failed=0
192.168.22.102             : ok=14   changed=6    unreachable=0    failed=0
192.168.22.103             : ok=14   changed=6    unreachable=0    failed=0
192.168.22.104             : ok=14   changed=6    unreachable=0    failed=0

This is not the whole output of the playbook. Important to know, during the “TASK [Test Ansible user’s access]” I had to insert the Ansible password 5 times. After that the playbooks finished successfully.

Ping the servers using Ansible

After the playbook finished successfully do a test ping

[root@dcos-ansible ansible-dcos]# ansible all -m ping
192.168.22.102 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}
192.168.22.100 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}
192.168.22.104 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}
192.168.22.101 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}
192.168.22.103 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}

In case of trouble it is really helpful to use the “-vvv” option.
It is also possible to ping only one server using

ansible 192.168.22.100 -m ping

Rollout the DC/OS installation

[root@dcos-ansible ansible-dcos]# pwd
/root/ansible-dcos
[root@dcos-ansible ansible-dcos]# cat plays/install.yml
---
- name: setup the system requirements on all nodes
  hosts: all
  serial: 20
  become: true
  roles:
    - common
    - docker

- name: generate the DC/OS configuration
  hosts: bootstraps
  serial: 1
  become: true
  roles:
    - bootstrap

- name: deploy nodes
  hosts: [ masters, agents, agent_publics]
  serial: 20
  become: true
  roles:
    - node-install

[root@dcos-ansible ansible-dcos]# pwd
/root/ansible-dcos
[root@dcos-ansible ansible-dcos]# ansible-playbook plays/install.yml

PLAY [setup the system requirements on all nodes]
*********************************************************************

TASK [Gathering Facts]
*********************************************************************
ok: [192.168.22.102]
ok: [192.168.22.104]
ok: [192.168.22.101]
ok: [192.168.22.100]
[....]

In case some installation steps fail, Ansible will skip for that server and gives you the opportunity to rerun the playbook on the failed server.

ansible-playbook plays/install.yml --limit @/root/ansible-dcos/plays/install.retry

If you cannot connect to your master via browser: Check your /var/log/messages for error messages. In my case the master searched for the eth0 interface. Which isn’t available on my VM.
Just change the detect-ip script as follows, according to your network interface. Same step is needed on all agent-nodes as well.

[root@dcos-master bin]# cat /opt/mesosphere/bin/detect_ip
#!/usr/bin/env bash
set -o nounset -o errexit
export PATH=/usr/sbin:/usr/bin:$PATH
echo $(ip addr show enp0s8 | grep -Eo '[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}' | head -1)

Install the CLI

For those of you, which prefer a CLI, just install it on your master.

[root@dcos-master ~]#  [ -d /usr/local/bin ] || sudo mkdir -p /usr/local/bin
[root@dcos-master ~]# curl https://downloads.dcos.io/binaries/cli/linux/x86-64/dcos-1.11/dcos -o dcos
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 13.9M  100 13.9M    0     0  1313k      0  0:00:10  0:00:10 --:--:-- 3920k
[root@dcos-master ~]# sudo mv dcos /usr/local/bin
[root@dcos-master ~]# chmod +x /usr/local/bin/dcos
[root@dcos-master ~]# dcos cluster setup http://192.168.22.101
If your browser didn't open, please go to the following link:

    http://192.168.22.101/login?redirect_uri=urn:ietf:wg:oauth:2.0:oob

Enter OpenID Connect ID Token: eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsImtpZCI6Ik9UQkVOakZFTWtWQ09VRTRPRVpGTlRNMFJrWXlRa015Tnprd1JrSkVRemRCTWpBM1FqYzVOZyJ9.eyJlbWFpbCI6Imp1bGlhLmd1Z2VsQGdtYWlsLmNvbSIsImVtYWlsX3ZlcmlmaWVkIjp0cnVlLCJpc3MiOiJodHRwczovL2Rjb3MuYXV0aDAuY29tLyIsInN1YiI6Imdvb2dsZS1vYXV0aDJ8MTA2NTU2OTI5OTM1NTc2MzQ1OTEyIiwiYXVkIjoiM3lGNVRPU3pkbEk0NVExeHNweHplb0dCZTlmTnhtOW0iLCJpYXQiOjE1NDA0NTA4MTcsImV4cCI6MTU0MDg4MjgxN30.M8d6dT4QNsBmUXbAH8B58K6Q2XvnCKnEd_yziiijBXHdW18P2OnJEYrKa9ewvOfFhyisvLa7XMU3xeBUhoqX5T6mGkQo_XUlxXM82Ohv3zNCdqyNCwPwoniX4vU7R736blcLRx1aB8TJnydNb0H0IzEAVzaYBQ1CRV-4a9KsiMXKBBPlskOSvek4b_FRghA6hsjMA2eO-G5r3B6UgHo6CCwdwVrhsOygvJ5NwDC0xiFrnkW-SjZRZztCN8cRj7b40VH43uY6R2ibxJfE7SaGpbWzLyp7juUJ766WXar3O7ww42bYIqLnAx6YmWG5kFeJnmJGT-Rdmhl2JuvdABoozA

That’s it, now you can configure and use your DC/OS. Always keep in mind: the ntpd service is really essential for a working DC/OS Node. Also use the /var/log/messages, it really helps!
One little thing I have to mention at the end. Don’t confide in the official documentation and the troubleshooting guide, it does not help as much as expected…

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Deploy DC/OS using Ansible (Part 2) – Playbooks

Create SSH Access

Start the Playbook for the SSH access

Ping the servers using Ansible

Rollout the DC/OS installation

Install the CLI

Gérard Wisson

Leave a Reply:

Related blog articles

Create SSH Access

Start the Playbook for the SSH access

Ping the servers using Ansible

Rollout the DC/OS installation

Install the CLI

Gérard Wisson

Leave a Reply:

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