Introduction - Percona Ansible to Manage...Redesigned UNIX connection layer and module runtime for...
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Transcript of Introduction - Percona Ansible to Manage...Redesigned UNIX connection layer and module runtime for...
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Introduction
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What does DO do?
Simple, Developer-focused Cloud Hosting
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What are we using
Ansible for?
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Example Deployment
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Example Project Layout
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Project Layout
● Inventories
● Local Module Library
● Group Variables / Host Variables
● Roles
○ Component roles
○ Project Specific Roles
● Playbooks
○ Server Templates
○ Cluster Configuration
○ Actions
● Makefiles
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Inventories
● List hosts (by environment)
● Define groups
● Guardrails
ansible-playbook -i inventories/development ...
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Inventories
● List hosts (by environment)
● Define groups
● Guardrails
all:
children:
mysql:
children:
mysql_managed:
hosts:
test-mysql-0[1:3].atlantic.com:
test-mysql-0[1:6].pacific.com:
mysql_unmanaged:
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Inventories
● List hosts (by environment)
● Define groups
● Guardrails
ansible-playbook ... --extra-vars="target_env=development” ...
Playbook:
---
- hosts: mysql:!mysql_unmanaged:&{{ target_env }}
...
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Inventories: Constructed Groups
plugin: constructed
strict: false
groups:
dev: inventory_hostname.startswith('dev-')
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Inventories: Constructed Groups
plugin: constructed
strict: false
groups:
dev_mysql: (group_names|intersect(['mysql', 'dev']))|length >= 2
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Inventories: Ordering
inventories
- development
- 10_mysql.yml
- 90_environment.yml
- 99_dev_mysql.yml
- production
- staging
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Variable Order of Precedence
1. command values (eg “-u user”)2. role defaults3. inventory file or script group vars4. inventory group_vars/all5. playbook group_vars/all6. inventory group_vars/*7. playbook group_vars/*8. inventory file or script host vars9. inventory host_vars/*
10. playbook host_vars/*11. host facts / cached set_facts
12. play vars13. play vars_prompt14. play vars_files15. role vars (defined in role/vars/main.yml)16. block vars (only for tasks in block)17. task vars (only for the task)18. include_vars19. set_facts / registered vars
20. role (and include_role) params21. include params22. extra vars (always win precedence)
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Variable Management
● Role defaults interface with the role● Define project level generic variables applicable to all environments
○ playbook group_vars/all○ playbook group_vars/*
● Host specific overrides○ inventory host_vars/*
● Variables we construct○ role vars / include_vars / set_facts
● Functional role variables○ role (and include_role) params
● Guardrails○ extra vars (always win precedence)
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Variable Management Example - Defaults---### proxysql installproxysql_create_image: "{{ global_create_image | default(false) }}"proxysql_download_src: https://github.com/sysown/proxysql/releases/downloadproxysql_version: 1.4.10proxysql_mysql_client_version: 5.7
proxysql_user: proxysqlproxysql_group: proxysqlproxysql_datadir: /var/lib/proxysqlproxysql_restart_missing_heartbeats: 10
...
# autocommitproxysql_mysql_autocommit_false_is_transaction: falseproxysql_mysql_autocommit_false_not_reusable: falseproxysql_mysql_enforce_autocommit_on_reads: falseproxysql_mysql_forward_autocommit: false
...
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Variable Management Example - Vars---...
### percona required packagesproxysql_release: "{{ proxysql_download_src }}/v{{ proxysql_version }}/proxysql_{{ proxysql_version }}-ubuntu18_amd64.deb"
...
proxysql_mysql_variables: autocommit_false_is_transaction: variable: "autocommit_false_is_transaction" variable_value: "{{ proxysql_mysql_autocommit_false_is_transaction | to_json }}" autocommit_false_not_reusable: variable: "autocommit_false_not_reusable" variable_value: "{{ proxysql_mysql_autocommit_false_not_reusable | to_json }}" client_found_rows: variable: "client_found_rows" variable_value: "{{ proxysql_mysql_client_found_rows | to_json }}"
...
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Variable Management Example - Config#jinja2: lstrip_blocks: "true"datadir="{{ proxysql_datadir }}"restart_on_missing_heartbeats={{ proxysql_restart_missing_heartbeats }}
admin_variables={{% for config_item in proxysql_admin_variables|dictsort %} {% if config_item.1.variable_value is not none %}
{{ config_item.1.variable }}={{ config_item.1.variable_value | to_json }}{% endif %}
{% endfor %}}
mysql_variables={{% for config_item in proxysql_mysql_variables|dictsort %} {% if config_item.1.variable_value is not none %}
{{ config_item.1.variable }}={{ config_item.1.variable_value | to_json }}{% endif %}
{% endfor %}}
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Anatomy of a Role
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Anatomy of a Role● A role should be map to a single unit of functionality that utilise a common set of variables.
● Roles should be intuitive, and wherever possible mimic a common structure.
● Role Variable Management
○ Where possible, a [component] role should be generic, and any variables should map
to sensible defaults.
○ The interface into role customisation should be via scalar role defaults.
○ Role variables should be used for variables that shouldn't be overridden in normal
circumstance, or as syntactic sugar to construct variables internal to the role.
● A role should have repeatable logic and should avoid logical branching that might be
non-repeatable.
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Component Roles
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Role Versioning
- name: role_mysql_proxysql
src: git+ssh://[email protected]/ansible/role_mysql_proxysql.git
version: 1.1.1
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Example ProxySQL Deployment
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Testing Roles
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● pip install --user molecule
○ pip install --user molecule[ec2]
○ pip install --user molecule[docker]
Molecule
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● create / destroy / list / cleanup
● prepare
● dependency
● login
Molecule Commands
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Anatomy of a Role
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● lint
● syntax
● idempotence
● verify
● check
Molecule Commands
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● converge
● test
● side-effects
Molecule Commands
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Role Development with Molecule
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Testing ProxySQL Example
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Molecule Configuration
dependency: name: galaxydriver: name: dockerlint: name: yamllintplatforms: - name: host1 image: "geerlingguy/docker-${MOLECULE_DISTRO:-ubuntu1804}-ansible:latest" command: ${MOLECULE_DOCKER_COMMAND:-""} volumes: - /sys/fs/cgroup:/sys/fs/cgroup:ro privileged: true pre_build_image: trueprovisioner: name: ansible lint: name: ansible-lint
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Molecule Configuration
scenario: name: default converge_sequence: # - dependency - create # - prepare - converge test_sequence: - lint - destroy # - dependency - syntax - create # - prepare - converge - idempotence # - side_effect - verify - destroy
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Molecule Configuration
verifier: name: testinfra env: PYTHONWARNINGS: "ignore:.*U.*mode is deprecated:DeprecationWarning" options: v: 1 lint: name: flake8
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Functional Testing with TestInfraproxysql_file_attributes = ("proxysql_file," "proxysql_file_user," "proxysql_file_group," "proxysql_file_mode")
@pytest.mark.parametrize(proxysql_file_attributes, [ ("/root/.my.cnf", None, None, 0o600), ("/etc/proxysql.cnf", "proxysql", "proxysql", 0o644),])def test_proxysql_files(host, proxysql_file, proxysql_file_user, proxysql_file_group, proxysql_file_mode): f = host.file(proxysql_file)
assert f.exists assert f.is_file if proxysql_file_user: assert f.user == proxysql_file_user if proxysql_file_group: assert f.group == proxysql_file_group if proxysql_file_mode: assert f.mode == proxysql_file_mode
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Functional Testing with TestInfra
● Host fixture
○ host.file
○ host.package
○ host.service
○ host.run
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Continuous Integration Pipeline
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User Management
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● Deployment and maintenance of individual and Service users
● Maintain user (dynamic) privileges
● Manage secrets (securely)
● Manage across both MySQL and ProxySQL
User Management Story
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Manual Worst Case Scenario
sammy
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User Management Requirements
● Deploy user control manifest to Ansible Project Role
● Generate & Encrypt secrets in Ansible Vault
● Consistent Delivery across technologies / tenancies / environments
● Scalable solution
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Request > New UMC > Gen Secret > commit/PR > Peer Review > Dry Run > Deploy
New User Deploy Chain
+ >> >> >>
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User Control Manifestsammy_ro: state: present active: true default_shard: atlantic default_hostgroup: swimming_pool default_schema: baby_shark enabled_schemas: - baby_shark - left_shark cluster_privs: atlantic: env: dev: - '%’ privs: - 'baby_shark.*:SELECT' pacific: env: dev: - '%’ privs: - 'left_shark.*:SELECT,INSERT,UPDATE,DELETE'
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docs.ansible.com/ansible/latest/modules/list_of_database_modules.html?#proxysql
proxysql_mysql_users
proxysql_query_rules
proxysql_replication_hostgroups
proxysql_scheduler
ProxySQL Ansible Module
proxysql_backend_servers
proxysql_global_variables
proxysql_manage_config
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Secret Storage
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Secret storage
Ansible Vault
● Used for shared secrets● Fine-grained access control
● Simple, no dependencies● Stored in repo w/ inventory &
playbooks
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Ansible Vault
Vault file per environment (dev/stage/production)
---monitoring_password: ooxalohquaiK8aidai0xbackup_password: ahvowooG9dohfashaCho
ansible-vault encrypt
$ANSIBLE_VAULT;1.2;AES256;production3538653766323031333335306239343730333830653630373731383863373638616461633438363135666136383566336661383263383566376361353637636231623034380a3263383163623935383666633463656664653532666338656539633430636266656230626232316662386639343233656439
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Ansible Vault
sammy_ro: dev: '*100569F51F55F3599CECBCABB9AC59AB29F30283' stage2: '*712E505DB01097F24D1B72509A820E254A525528' production: '*1A0174A0F2F4692917994C19C158F96B1914A53F'sammy_rw: dev: '*0A5B11132F429A38988540A351C60A620DE5BBFA' stage2: '*8B5CCFF05B945DED591D603DF936805476E77837' production: '*C0BF0057A4AC079E7ABE2FEC54DC87A1680B95DC'
Two vault files for all password hashes
● Passwords distributed to users via LastPass● Ansible never needs password, just hash
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Ansible Vault
Challenges of ansible-vault approach:
● Merge conflicts● Visibility / discoverability
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diffing Ansible vaults
$ git diff individuals.yml $ANSIBLE_VAULT;1.1;AES256-6530653733663966316630613666393-6139303463613133633262643034633-3235346162366237366538653361653...+3938303335363632343730656164356+3433373263346136653730313636336+3862633932353039616334303631376
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diffing Ansible vaults
.gitconfig:[diff "ansible-vault"]
textconv = ansible-vault viewcachetextconv = false
.gitattributes:individuals.yml diff=ansible-vault
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diffing Ansible vaults
$ git diff individuals.yml sammy_rw: dev: '*0A5B11132F429A3898854' stage2: '*8B5CCFF05B945DED59837'- production: '*C0BF0057A4AC0780B95DC'+ production: '*B1E8174F9DCE654C25608'
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Similar config for merge
/usr/local/bin/ansible-vault-merge
.gitconfig:[merge "ansible-vault"]
name = ansible-vault merge driverdriver = /usr/local/bin/ansible-vault-merge -- %O %A %B %P
.gitattributes:individuals.yml diff=ansible-vault merge=ansible-vault
See github.com/building5/ansible-vault-tools
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Finding variables in vault
Where is backup_password defined?
● Variable prefix○ In vars.yml: backup_password: "{{ vault_backup_password }}"○ In vault.yml: vault_backup_password: ahvowooG9dohfashaCho
● git grep:$ git grep --textconv backup_passwordvars.yml:backup_password: "{{ vault_backup_password }}"vault.yml:vault_backup_password: ahvowooG9dohfashaCho
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Ansible vault passwords
● Store in local file○ Exclude from git!○ Can be executable
● Can define multiple vault-ids:
[defaults]vault_identity_list = [email protected],[email protected]
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HashiCorp Vault
For secrets shared with others
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HashiCorp Vault
# Set VAULT_ADDR$ vault login# Set VAULT_TOKEN
$ vault write secret/sammy pass=Za6Uoy
$ vault read secret/sammyKey Value--- -----pass Za6Uoy
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HashiCorp Vault
● hashi_vault lookup plugin○ https://docs.ansible.com/ansible/latest/plugins/lookup/hashi
_vault.html
● Various auth methods○ We use approle and token
● Auth secret stored in environment variable or in Ansible vault
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HashiCorp Vault
- copy: content: >- {{ lookup('hashi_vault', 'secret=secret/sammy_cert:cert url=https://vault.example.com:8200 auth_method=approle role_id={{ role_id }} secret_id={{ secret_id }} ) }} dest: /etc/nginx/ssl/certificate.crt
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HashiCorp Vault
Why not HashiCorp Vault for everything?
● External dependency● Changing policies requires another commit and
approval by another team
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Ansible Performance
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Performance Visibility
ansible.cfg
callback_whitelist = profile_tasks, profile_roles, timer
stdout_callback = actionable
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Performance
● SSH optimisations
● Gathering Facts
● Play Logic
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Performance
● SSH optimisations
● Gathering Facts
● Play Logic
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A mitogen is a chemical substance, usually a protein, that induces a cell to begin cell division
Mitogen for AnsibleAn Ansible Plugin that replaces the use of SSH
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Mitogen for Ansible
● Redesigned UNIX connection layer and module runtime for Ansible
● Easy installation, minimal configuration
● Immediate gains (immediately) 1% - 7% improvement in run duration
*unless you have and it didn’t help (Windows, Networking equipment)
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Performance Challenges
● Loopy Loops
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Module Override
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With pushdown Without mitogen
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With pushdown With mitogen
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Without pushdown Without mitogen
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Without pushdown With mitogen
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Mitogen SSH Only
Standard mysql_user 4m 23s 10m 6s
Patched mysql_user 7m 33s 8m 19s
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