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Catch Up Ansible! How to Start Ansible

Ansibleに取り組むので自分の学習経路をメモしておく。

https://sonnguyen.ws/wp-content/uploads/2016/01/how-to-use-ansible-1024x300.png

公式Document

流し読みしたけど、なんとなく全体感がわからない

Ansible Documentation — Ansible Documentation

英語だけど動画がなんとなく全体像捉えるにはわかりやすい。 英語聞けなくても、スライドでなんとなく要素はつかめる。 What is Ansible? | Ansible Quick Start Video

スライドをベースにまず要素を学んで、そのあとフォルダ構成をみると、おぉって感じになるのでオススメ。

全体感

要素

  • Playbook … Chefで言うレシピ
  • Vars … 変数を定義できる
  • Inventory … 実行対象ホスト群とそれをまとめるグループを定義出来る

Playbook

Chefのレシピ的なもの。

f:id:umisora2:20170815155506p:plain

f:id:umisora2:20170815160243p:plain

f:id:umisora2:20170815162428p:plain

f:id:umisora2:20170815162443p:plain f:id:umisora2:20170815161315p:plain

Vars

変数管理的なもの

f:id:umisora2:20170815155659p:plain * 色んなパターン、場所でVarsが設定出来るよ。 * group_vars * host_vars

Ansible (8) Ansible Tower:概要とインストール – CLARA ONLINE techblog

Inventories

実行先ホストの定義

f:id:umisora2:20170815160041p:plain * 1行づつ記載も出来るし * グルーピングも出来る * AWS等から動的にリストを取得もできる

実行方法

f:id:umisora2:20170815161422p:plain

Ad-Hoc Command

ansible <host-pattern> [options]

$> ansible --version
ansible 2.3.1.0
 
$> ansible -h
Usage: ansible <host-pattern> [options]

Options:
  -a MODULE_ARGS, --args=MODULE_ARGS
                        module arguments
  --ask-vault-pass      ask for vault password
  -B SECONDS, --background=SECONDS
                        run asynchronously, failing after X seconds
                        (default=N/A)
  -C, --check           don't make any changes; instead, try to predict some
                        of the changes that may occur
  -D, --diff            when changing (small) files and templates, show the
                        differences in those files; works great with --check
  -e EXTRA_VARS, --extra-vars=EXTRA_VARS
                        set additional variables as key=value or YAML/JSON
  -f FORKS, --forks=FORKS
                        specify number of parallel processes to use
                        (default=5)
  -h, --help            show this help message and exit
  -i INVENTORY, --inventory-file=INVENTORY
                        specify inventory host path
                        (default=/usr/local/etc/ansible/hosts) or comma
                        separated host list.
  -l SUBSET, --limit=SUBSET
                        further limit selected hosts to an additional pattern
  --list-hosts          outputs a list of matching hosts; does not execute
                        anything else
  -m MODULE_NAME, --module-name=MODULE_NAME
                        module name to execute (default=command)
  -M MODULE_PATH, --module-path=MODULE_PATH
                        specify path(s) to module library (default=None)
  --new-vault-password-file=NEW_VAULT_PASSWORD_FILE
                        new vault password file for rekey
  -o, --one-line        condense output
  --output=OUTPUT_FILE  output file name for encrypt or decrypt; use - for
                        stdout
  -P POLL_INTERVAL, --poll=POLL_INTERVAL
                        set the poll interval if using -B (default=15)
  --syntax-check        perform a syntax check on the playbook, but do not
                        execute it
  -t TREE, --tree=TREE  log output to this directory
  --vault-password-file=VAULT_PASSWORD_FILE
                        vault password file
  -v, --verbose         verbose mode (-vvv for more, -vvvv to enable
                        connection debugging)
  --version             show program's version number and exit

  Connection Options:
    control as whom and how to connect to hosts

    -k, --ask-pass      ask for connection password
    --private-key=PRIVATE_KEY_FILE, --key-file=PRIVATE_KEY_FILE
                        use this file to authenticate the connection
    -u REMOTE_USER, --user=REMOTE_USER
                        connect as this user (default=None)
    -c CONNECTION, --connection=CONNECTION
                        connection type to use (default=smart)
    -T TIMEOUT, --timeout=TIMEOUT
                        override the connection timeout in seconds
                        (default=10)
    --ssh-common-args=SSH_COMMON_ARGS
                        specify common arguments to pass to sftp/scp/ssh (e.g.
                        ProxyCommand)
    --sftp-extra-args=SFTP_EXTRA_ARGS
                        specify extra arguments to pass to sftp only (e.g. -f,
                        -l)
    --scp-extra-args=SCP_EXTRA_ARGS
                        specify extra arguments to pass to scp only (e.g. -l)
    --ssh-extra-args=SSH_EXTRA_ARGS
                        specify extra arguments to pass to ssh only (e.g. -R)

  Privilege Escalation Options:
    control how and which user you become as on target hosts

    -s, --sudo          run operations with sudo (nopasswd) (deprecated, use
                        become)
    -U SUDO_USER, --sudo-user=SUDO_USER
                        desired sudo user (default=root) (deprecated, use
                        become)
    -S, --su            run operations with su (deprecated, use become)
    -R SU_USER, --su-user=SU_USER
                        run operations with su as this user (default=root)
                        (deprecated, use become)
    -b, --become        run operations with become (does not imply password
                        prompting)
    --become-method=BECOME_METHOD
                        privilege escalation method to use (default=sudo),
                        valid choices: [ sudo | su | pbrun | pfexec | doas |
                        dzdo | ksu | runas ]
    --become-user=BECOME_USER
                        run operations as this user (default=root)
    --ask-sudo-pass     ask for sudo password (deprecated, use become)
    --ask-su-pass       ask for su password (deprecated, use become)
    -K, --ask-become-pass
                        ask for privilege escalation password

Playbook

ansible-playbook playbook.yml

$ ansible-playbook -h
Usage: ansible-playbook playbook.yml

Options:
  --ask-vault-pass      ask for vault password
  -C, --check           don't make any changes; instead, try to predict some
                        of the changes that may occur
  -D, --diff            when changing (small) files and templates, show the
                        differences in those files; works great with --check
  -e EXTRA_VARS, --extra-vars=EXTRA_VARS
                        set additional variables as key=value or YAML/JSON
  --flush-cache         clear the fact cache
  --force-handlers      run handlers even if a task fails
  -f FORKS, --forks=FORKS
                        specify number of parallel processes to use
                        (default=5)
  -h, --help            show this help message and exit
  -i INVENTORY, --inventory-file=INVENTORY
                        specify inventory host path
                        (default=/usr/local/etc/ansible/hosts) or comma
                        separated host list.
  -l SUBSET, --limit=SUBSET
                        further limit selected hosts to an additional pattern
  --list-hosts          outputs a list of matching hosts; does not execute
                        anything else
  --list-tags           list all available tags
  --list-tasks          list all tasks that would be executed
  -M MODULE_PATH, --module-path=MODULE_PATH
                        specify path(s) to module library (default=None)
  --new-vault-password-file=NEW_VAULT_PASSWORD_FILE
                        new vault password file for rekey
  --output=OUTPUT_FILE  output file name for encrypt or decrypt; use - for
                        stdout
  --skip-tags=SKIP_TAGS
                        only run plays and tasks whose tags do not match these
                        values
  --start-at-task=START_AT_TASK
                        start the playbook at the task matching this name
  --step                one-step-at-a-time: confirm each task before running
  --syntax-check        perform a syntax check on the playbook, but do not
                        execute it
  -t TAGS, --tags=TAGS  only run plays and tasks tagged with these values
  --vault-password-file=VAULT_PASSWORD_FILE
                        vault password file
  -v, --verbose         verbose mode (-vvv for more, -vvvv to enable
                        connection debugging)
  --version             show program's version number and exit

  Connection Options:
    control as whom and how to connect to hosts

    -k, --ask-pass      ask for connection password
    --private-key=PRIVATE_KEY_FILE, --key-file=PRIVATE_KEY_FILE
                        use this file to authenticate the connection
    -u REMOTE_USER, --user=REMOTE_USER
                        connect as this user (default=None)
    -c CONNECTION, --connection=CONNECTION
                        connection type to use (default=smart)
    -T TIMEOUT, --timeout=TIMEOUT
                        override the connection timeout in seconds
                        (default=10)
    --ssh-common-args=SSH_COMMON_ARGS
                        specify common arguments to pass to sftp/scp/ssh (e.g.
                        ProxyCommand)
    --sftp-extra-args=SFTP_EXTRA_ARGS
                        specify extra arguments to pass to sftp only (e.g. -f,
                        -l)
    --scp-extra-args=SCP_EXTRA_ARGS
                        specify extra arguments to pass to scp only (e.g. -l)
    --ssh-extra-args=SSH_EXTRA_ARGS
                        specify extra arguments to pass to ssh only (e.g. -R)

  Privilege Escalation Options:
    control how and which user you become as on target hosts

    -s, --sudo          run operations with sudo (nopasswd) (deprecated, use
                        become)
    -U SUDO_USER, --sudo-user=SUDO_USER
                        desired sudo user (default=root) (deprecated, use
                        become)
    -S, --su            run operations with su (deprecated, use become)
    -R SU_USER, --su-user=SU_USER
                        run operations with su as this user (default=root)
                        (deprecated, use become)
    -b, --become        run operations with become (does not imply password
                        prompting)
    --become-method=BECOME_METHOD
                        privilege escalation method to use (default=sudo),
                        valid choices: [ sudo | su | pbrun | pfexec | doas |
                        dzdo | ksu | runas ]
    --become-user=BECOME_USER
                        run operations as this user (default=root)
    --ask-sudo-pass     ask for sudo password (deprecated, use become)
    --ask-su-pass       ask for su password (deprecated, use become)
    -K, --ask-become-pass
                        ask for privilege escalation password

Dry-runもありますよー。 f:id:umisora2:20170815162521p:plain

ディレクトリ構成

Best Practices — Ansible Documentation

Ansible ( 俺の中で ) 最強の Best Practices - Qiita

うんうん。Itamaeと比べるとファイルの種類/区分けが多くて少し目が回るね。 あれとあれの共通。みたいなののパターンが増えている状態を全てフォルダ化したらこうなる気がするね。 なんとなく全体像わかった。

最後に、

私はItamaeで必要十分に実行が出来てたので Itamaeと同じ機能レベルが揃ってれば良くて、特徴的なのは

  • レシピをincludeして階層構造に出来る事 → 出来る
  • subscribes で条件に応じて依存レシピが実行できる、コマンドが実行できる事。 これを調査中。 Ansibleのroleを使いこなす - Qiita