ansible for devops 读书笔记第二章Ad-Hoc Commands

• 参数

• 参数	说明
  -a	‘Arguments’, —args=’Arguments’ 命令行参数
  -m	NAME, —module-name=NAME 执行模块的名字，默认使用 command 模块，所以如果是只执行单一命令可以不用 -m参数
  -i PATH,	—inventory=PATH 指定库存主机文件的路径,默认为/etc/ansible/hosts.
  -u Username，	—user=Username 执行用户，使用这个远程用户名而不是当前用户
  -U	—sud-user=SUDO_User sudo到哪个用户，默认为 root
  -k	—ask-pass 登录密码，提示输入SSH密码而不是假设基于密钥的验证
  -K	—ask-sudo-pass 提示密码使用sudo
  -s	—sudo sudo运行
  -S	—su 用 su 命令
  -l	—list 显示所支持的所有模块
  -s	—snippet 指定模块显示剧本片段
  -f	—forks=NUM 并行任务数。NUM被指定为一个整数,默认是5。 #ansible testhosts -a “/sbin/reboot” -f 10 重启testhosts组的所有机器，每次重启10台
  —private-key=PRIVATE_KEY_FILE	私钥路径，使用这个文件来验证连接
  -v	—verbose 详细信息
  all	针对hosts 定义的所有主机执行
  -M MODULE_PATH,	—module-path=MODULE_PATH 要执行的模块的路径，默认为/usr/share/ansible/
  —list-hosts	只打印有哪些主机会执行这个 playbook 文件，不是实际执行该 playbook 文件
  -o —one-line	压缩输出，摘要输出.尝试一切都在一行上输出。
  -t Directory,	—tree=Directory 将内容保存在该输出目录,结果保存在一个文件中在每台主机上。
  -B	后台运行超时时间
  -P	调查后台程序时间
  -T Seconds,	—timeout=Seconds 时间，单位秒s
  -P NUM,	—poll=NUM 调查背景工作每隔数秒。需要- b
  -c Connection,	—connection=Connection 连接类型使用。可能的选项是paramiko(SSH),SSH和地方。当地主要是用于crontab或启动。
  —tags=TAGS	只执行指定标签的任务 例子:ansible-playbook test.yml –tags=copy 只执行标签为copy的那个任务
  —list-tasks	列出所有将被执行的任务
  -C,	—check 只是测试一下会改变什么内容，不会真正去执行;相反,试图预测一些可能发生的变化
  —syntax-check	执行语法检查的剧本,但不执行它
  -l SUBSET,	—limit=SUBSET 进一步限制所选主机/组模式 –limit=192.168.0.15 只对这个ip执行
  —skip-tags=SKIP_TAGS	只运行戏剧和任务不匹配这些值的标签 —skip-tags=copy_start
  -e EXTRA_VARS,	—extra-vars=EXTRA_VARS 额外的变量设置为键=值或YAML / JSON
  -l	—limit 对指定的 主机/组 执行任务 —limit=192.168.0.10，192.168.0.11 或 -l 192.168.0.10，192.168.0.11 只对这个2个ip执行任务

• Inventory file for multiple servers
  • vim /etc/ansible/hosts

  • # Application servers
    [app]
    192.168.60.4
    192.168.60.5
    
    # Database server
    [db]
    192.168.60.6
    
    # Group 'multi' with all servers
    [multi:children]
    app
    db
    
    # Variables that will be applied to all servers
    [multi:vars]
    ansible_ssh_user=vagrant
    ansible_ssh_private_key_file=~/.vagrant.d/insecure_private_key
    

    1.The first block puts both of our application servers into an ‘app’ group.

  • 2. The second block puts the database server into a ‘db’ group.

  • 3. The third block tells ansible to define a new group ‘multi’, with child groups, and we add in both the ‘app’ and ‘db’ groups.

  • 4. The fourth block adds variables to the multi group that will be applied to all servers within multi and all its children

• ansible multi -a "hostname"
• ansible multi -a "hostname" -f 1  这一次是只是用了一个线程
• servers have disk space available for our application:
  • ansible multi -a "df -h"
• make sure there is enough memory on our servers
  • 　ansible multi -a "free -m"
• Make changes using Ansible modules
  • ansible multi -s -m yum -a "name=ntp state=present"    -s 的意思是sudo
  • ansible multi -s -m service -a "name=ntpd state=started enabled=yes"
  • ansible multi -s -a "service ntpd stop"
  • ansible multi -s -a "ntpdate -q 0.rhel.pool.ntp.org"
  • ansible multi -s -a "service ntpd start"
• Configure groups of servers, or individual servers
  • ansible app -s -m yum -a "name=MySQL-python state=present"
  • ansible app -s -m yum -a "name=python-setuptools state=present"
  • ansible app -s -m easy_install -a "name=django"
  • ansible app -a "python -c 'import django; print django.get_version()'"
•  Configure the Database servers
  •  ansible db -s -m yum -a "name=mariadb-server state=present"
  • ansible db -s -m service -a "name=mariadb state=started enabled=yes"
  • ansible db -s -a "iptables -F"

  • ansible db -s -a "iptables -A INPUT -s 192.168.60.0/24 -p tcp \
    -m tcp --dport 3306 -j ACCEPT"

  • ansible db -s -m yum -a "name=MySQL-python state=present"

  • ansible db -s -m mysql_user -a "name=django host=% password=12345 \
    priv=*.*:ALL state=present"

• Make changes to just one server
  •  ansible app -s -a "service ntpd status"
  • ansible app -s -a "service ntpd restart" --limit "192.168.60.4"　limit后还可以用正则比如 --limit "*.4"    --limit ~".*\.4"
• Manage users and groups
  • ansible app -s -m group -a "name=admin state=present"
  • ansible app -s -m user -a "name=johndoe group=admin createhome=yes"
  • $ ansible app -s -m user -a "name=johndoe state=absent remove=yes"
• Manage files and directories
  • Get information about a file　
    • ansible multi -m stat -a "path=/etc/environment"
  • Copy a file to the servers
    • ansible multi -m copy -a "src=/etc/hosts dest=/tmp/hosts"
  • Retrieve a file from the servers     
    • ansible multi -s -m fetch -a "src=/etc/hosts dest=/tmp"      远程服务器拉取文件至本机，只能fetch文件，不能fetch目录,如果拉目录，先tar/zip 再拉到本机即可
  • Create directories and files　
    • ansible multi -m file -a "dest=/tmp/test mode=644 state=directory"

    • ansible multi -m file -a "src=/src/symlink dest=/dest/symlink \
      owner=root group=root state=link"

  • Delete directories and files　　
    • ansible multi -m file -a "dest=/tmp/test state=absent"　
• Run operations in the background 
  • ansible multi -s -B 3600 -a "yum -y update"     　
  • ansible multi -s -m async_status -a "jid=763350539037"     

    check on the status elsewhere using Ansible’s
    async_status module

  • Fire-and-forget tasks
    • ansible multi -B 3600 -P 0 -a "/path/to/fire-and-forget-script.sh"
• Check log files
  • ansible multi -s -a "tail /var/log/messages"
• Manage cron jobs
  • ansible multi -s -m cron -a "name='daily-cron-all-servers' \

    hour=4 job='/path/to/daily-script.sh'

  •  ansible multi -s -m cron -a "name='daily-cron-all-servers' state=absent"       删掉