Ansible 기본4(Facts)

2024.03.11 - [Ansible] - Ansible 기본1(설치 후 기본 활용)

Ansible 기본1(설치 후 기본 활용)

2024.03.26 - [Ansible] - Ansible 기본2(변수)

Ansible 기본2(변수)

2024.03.26 - [Ansible] - Ansible 기본3(Ansible Vault)

Ansible 기본3(Ansible Vault)

---

Ansible 실무에 활용 전 vm 통해 테스트하는 방법 안내하도록 하겠습니다.
관련하여 Ansible 사용하실분들은 참고하여 실무에 적용하시면 좋을 것 같습니다.
무작정 따라하시기보다, 내용 변경해가며 따라하시는걸 추천드립니다.

서버 정보

ansible-control	Ubuntu 22.04	4vcore	8GB	80GB	10.10.x.123
ansible1	Ubuntu 22.04	4vcore	8GB	80GB	10.10.x.124
ansible2	Ubuntu 22.04	4vcore	8GB	80GB	10.10.x.125
ansible3	Ubuntu 22.04	4vcore	8GB	80GB	10.10.x.126

---

설정파일 수정이 많다보니 vscode로 진행했습니다.
DevOps 업무하게 되면 vscode에 익숙해져야 할 것 같네요.

https://code.visualstudio.com/

Visual Studio Code - Code Editing. Redefined

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Facts 자동으로 검색한 변수

Discovering variables: facts and magic variables

- Facts 사용하기 : 기본 활성화로, 플레이북을 실행할 때 자동으로 팩트가 수집됨. ansible_facts 변수로 사용.

• ansible/facts.yml

---

- hosts: db

  tasks:
  - name: Print all facts
    ansible.builtin.debug:
      var: ansible_facts

• 실행

#
ansible-playbook facts.yml
...
"default_ipv4": {
    "address": "10.10.x.126",
"fqdn": "ansible3",
...
"kernel": "6.5.0-17-generic"
...

• ansible/facts1.yml

# 파일 복사
cp facts.yml facts1.yml

# facts1.yml 파일 편집
---

- hosts: db

  tasks:
  - name: Print all facts
    ansible.builtin.debug:
      msg: >
        The default IPv4 address of {{ ansible_facts.fqdn }}
        is {{ ansible_facts.default_ipv4.address }}

• 실행

#
ansible-playbook facts1.yml
...
TASK [Gathering Facts] **********************************************************************************************************************************************************************************************************************
ok: [ansible3]

TASK [Print all facts] **********************************************************************************************************************************************************************************************************************
ok: [ansible3] => {
    "msg": "The default IPv4 address of ansible3 is 10.10.x.126"
}

---

- 변수로 사용할 수 있는 Ansible Facts

• ansible/facts2.yml

# 파일 복사
cp facts1.yml facts2.yml

# facts2.yml 파일 편집
---

- hosts: db

  tasks:
  - name: Print all facts
    ansible.builtin.debug:
      msg: >
        The node's host name is {{ ansible_hostname }}
        and the ip is {{ ansible_default_ipv4.address }}

• 실행

#
ansible-playbook facts2.yml
...
TASK [Print all facts] **********************************************************************************************************************************************************************************************************************
ok: [ansible3] => {
    "msg": "The node's host name is ansible3 and the ip is 10.10.x.126"
}

• ansible.cfg 수정 후 실행

# ansible.cfg 파일 편집
[defaults]
inventory = ./inventory
remote_user = root
ask_pass = false
inject_facts_as_vars = false  ##추가

[privilege_escalation]
become = true
become_method = sudo
become_user = root
become_ask_pass = false

# 실행
ansible-playbook facts2.yml

---

- Facts 수집 끄기

• ansible/facts3.yml

# 파일 복사
cp facts1.yml facts3.yml

# facts3.yml 파일 편집
---

- hosts: db
  gather_facts: no

  tasks:
  - name: Print all facts
    ansible.builtin.debug:
      msg: >
        The default IPv4 address of {{ ansible_facts.fqdn }}
        is {{ ansible_facts.default_ipv4.address }}

• 실행

# 실행 결과 확인 : 팩트를 수집하지 않았는데, 팩트에서 수집해야만 하는 변수를 사용하려고 해서 에러가 발생
ansible-playbook facts3.yml

# 파일 복사
cp facts3.yml facts3-2.yml

# facts3-2.yml 파일 편집
---

- hosts: db
  gather_facts: no

  tasks:
  - name: Print message
    debug:
      msg: Hello Ansible World

# 실행 : TASK [Print all facts] 가 없다!
ansible-playbook facts3-2.yml
PLAY [db] ***************************************************************************

TASK [Print message] ***************************************************************************************
ok: [ansible3] => {
    "msg": "Hello Ansible World"
}
...

• ansible/facts4.yml

# 파일 복사
cp facts3.yml facts4.yml

# facts4.yml 파일 편집
---

- hosts: db
  gather_facts: no

  tasks:
  - name: Manually gather facts
    ansible.builtin.setup:

  - name: Print all facts
    ansible.builtin.debug:
      msg: >
        The default IPv4 address of {{ ansible_facts.fqdn }}
        is {{ ansible_facts.default_ipv4.address }}

• 실행

#
ansible-playbook facts4.yml
...
TASK [Manually gather facts] *******************************************************************************
ok: [ansible3]

TASK [Print all facts] *************************************************************************************
ok: [ansible3] => {
    "msg": "The default IPv4 address of ansible3 is 10.10.x.126"
}

---

도전과제3 Facts를 사용하여 3개의 VM의 ‘커널 버전’과 ‘운영체제 종류’를 출력해보자

 

# 파일 복사
cp facts3.yml facts6.yml

# facts6.yml 파일 편집
---

- hosts: all
  gather_facts: no

  tasks:
  - name: Manually gather facts
    ansible.builtin.setup:

  - name: Print all facts
    ansible.builtin.debug:
      msg: >
        The kernel_version is {{ ansible_facts.kernel }}
        The OS is {{ ansible_facts.lsb.description }}

# 실행
ansible-playbook facts6.yml
TASK [Manually gather facts] ****************************************************************************************************************************************************************************************************************
ok: [ansible3]
ok: [ansible2]
ok: [ansible1]

TASK [Print all facts] **********************************************************************************************************************************************************************************************************************
ok: [ansible1] => {
    "msg": "The kernel_version is 6.5.0-17-generic is Ubuntu 22.04.4 LTS"
}
ok: [ansible2] => {
    "msg": "The kernel_version is 6.5.0-17-generic is Ubuntu 22.04.4 LTS"
}
ok: [ansible3] => {
    "msg": "The kernel_version is 6.5.0-17-generic is Ubuntu 22.04.4 LTS"
}

PLAY RECAP **********************************************************************************************************************************************************************************************************************************
ansible1                   : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   
ansible2                   : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   
ansible3                   : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0