红帽RHCE之Ansible-1-介绍及实验环境准备

Ansible-1-介绍及实验环境准备

Ansible介绍

• ansible是新出现的自动化运维工具，基于Python开发，集合了众多运维工具（puppet、cfengine、chef、func、fabric）的优点，实现了批量系统配置、批量程序部署、批量运行命令等功能。
  ansible是基于模块工作的，本身没有批量部署的能力。真正具有批量部署的是ansible所运行的模块，ansible只是提供一种框架。主要包括：
  (1)、连接插件connection plugins：负责和被监控端实现通信；
  (2)、host inventory：指定操作的主机，是一个配置文件里面定义监控的主机；
  (3)、各种模块核心模块、command模块、自定义模块；
  (4)、借助于插件完成记录日志邮件等功能；
  (5)、playbook：剧本执行多个任务时，非必需可以让节点一次性运行多个任务。

Ansible，实验环境准备

在rh294的机器里面有七个基于KVM的虚拟机，分别如下：

• workstation虚拟机（作为Ansible Control host）；
• Servera，Serverb，Serverc，Serverd（作为Ansible managed host）；
• bastion（提供了一个外部网络）；
• classroom虚拟机（提供了联系环境脚本，软件仓库，课程材料）

1、这些虚拟机的启动顺序：先启动classroom，再启动剩下的所有的虚拟机，刚开始的环境，虚拟机并没有在环境中存在，需要使用命令拉取虚拟机；

//rhl-vmctl命令就是rhl tools
//rht-vmctl fullreset的意思是完全重置某个虚拟机（虚拟机的删除重建）
[kiosk@foundation0 ~]$ rht-vmctl fullreset classroom 
Are you sure you want to full reset classroom? (y/n) y
Powering off classroom.
Full resetting classroom.
Creating virtual machine disk overlay for rh294-classroom-vda.qcow2
Starting classroom.

//虚拟机，不要动这个目录
[kiosk@foundation0 vms]$ pwd
/content/rhel8.0/x86_64/vms
[kiosk@foundation0 vms]$ ls
rh294-bastion-vda.qcow2  rh294-servera-vdb.qcow2  rh294-serverb-vdb.qcow2  rh294-serverc-vdb.qcow2  rh294-serverd-vdb.qcow2  rh294-workstation-vda.qcow2
rh294-bastion.xml        rh294-servera.xml        rh294-serverb.xml        rh294-serverc.xml        rh294-serverd.xml        rh294-workstation.xml
rh294-servera-vda.qcow2  rh294-serverb-vda.qcow2  rh294-serverc-vda.qcow2  rh294-serverd-vda.qcow2  rh294-vms.md5sum

2、classroom启动之后，我们第一次加载环境，需要将其他的虚拟机文件全部加载到环境里面

//将除了classroom之外的所有虚拟机全部删除重建
[kiosk@foundation0 vms]$ rht-vmctl fullreset all

即使你有KVM虚拟化管理经验，也不建议你用KVM的相关操作来管理

[root@foundation0 ~]# virsh list
 Id    Name                           State
----------------------------------------------------
 1     classroom                      running
 2     bastion                        running
 3     workstation                    running
 4     servera                        running
 5     serverb                        running
 6     serverc                        running
 7     serverd                        running

强烈建议使用rhl tools来管理这些虚拟机

//查看所有虚拟机的状态
[root@foundation0 ~]# rht-vmctl status all
bastion RUNNING
workstation RUNNING
servera RUNNING
serverb RUNNING
serverc RUNNING
serverd RUNNING
[root@foundation0 ~]# rht-vmctl status classroom 
classroom RUNNING

//将所有虚拟机恢复快照，不包括classroom
[root@foundation0 ~]# rht-vmctl reset all
Are you sure you want to reset bastion workstation servera serverb serverc serverd? (y/n) y
Powering off bastion..
Powering off workstation..
Powering off servera..
Powering off serverb..
Powering off serverc..
Powering off serverd..
Resetting bastion.
Creating virtual machine disk overlay for rh294-bastion-vda.qcow2
Starting bastion.
Resetting workstation.
Creating virtual machine disk overlay for rh294-workstation-vda.qcow2
Starting workstation.
Resetting servera.
Creating virtual machine disk overlay for rh294-servera-vda.qcow2
Creating virtual machine disk overlay for rh294-servera-vdb.qcow2
Starting servera.
Resetting serverb.
Creating virtual machine disk overlay for rh294-serverb-vda.qcow2
Creating virtual machine disk overlay for rh294-serverb-vdb.qcow2
Starting serverb.
Resetting serverc.
Creating virtual machine disk overlay for rh294-serverc-vda.qcow2
Creating virtual machine disk overlay for rh294-serverc-vdb.qcow2
Starting serverc.
Resetting serverd.
Creating virtual machine disk overlay for rh294-serverd-vda.qcow2
Creating virtual machine disk overlay for rh294-serverd-vdb.qcow2
Starting serverd.

//开启所有虚拟机
[root@foundation0 ~]# rht-vmctl start all

命令查看

[root@foundation0 ~]# rht-vmctl
Error: missing subcommand or VMNAME.

This utility manages the Red Hat Training supplied VMs on the local
hypervisor.

Usage: rht-vmctl [-y|--yes] VMCMD VMNAME [DATETIME]
       rht-vmctl [-i|--inquire] VMCMD VMNAME [DATETIME]
       rht-vmctl -h|--help

  where VMCMD is one of:
    view       - launches console viewer of VMNAME
    start      - obtain and start up VMNAME
    stop       - stop a running VMNAME
    restart    - if running, stop then start VMNAME
    poweroff   - if running, force stop VMNAME
    reset      - poweroff, return to saved or original state, start VMNAME
    save       - stop, save image, start VMNAME (to DATETIME)
    restore    - poweroff, restore to save (to DATETIME), start VMNAME
    listsaves  - list the saves of VMNAME
    status     - display libvirt status of VMNAME
    get        - if not here, obtain VMNAME from server
    remove     - remove VMNAME from system
    fullreset  - poweroff, reobtain from server, start VMNAME (bad save/image)

  -i|--inquire - confirm each VMNAME first
  -y|--yes     - confirm nothing, just do it

  VMNAME of "all" processes all VMs available in the course

3、实验环境的主机解析文件

//环境主机都已经免密登录
[root@foundation0 ~]# ssh workstation
Warning: Permanently added 'workstation,172.25.250.9' (ECDSA) to the list of known hosts.
Activate the web console with: systemctl enable --now cockpit.socket

[student@workstation ~]$ cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

172.25.254.254	classroom.example.com classroom
172.25.254.254	content.example.com content
172.25.254.254	materials.example.com materials
### rht-vm-hosts file listing the entries to be appended to /etc/hosts
#
172.25.250.9    workstation.lab.example.com      workstation
172.25.250.10   servera.lab.example.com servera
172.25.250.11   serverb.lab.example.com serverb
172.25.250.12   serverc.lab.example.com serverc
172.25.250.13   serverd.lab.example.com serverd
172.25.250.254	bastion.lab.example.com bastion

[root@foundation0 ~]# bridge link
6: virbr1-nic:  mtu 1500 master virbr1 state disabled priority 32 cost 100 
8: br1-nic:  mtu 1500 master br1 state disabled priority 32 cost 100 
10: privbr0-nic:  mtu 1500 master privbr0 state disabled priority 32 cost 100 
12: virbr0-nic:  mtu 1500 master virbr0 state disabled priority 32 cost 100 
13: vnet0:  mtu 1500 master br0 state forwarding priority 32 cost 100 
14: vnet1:  mtu 1500 master br1 state forwarding priority 32 cost 100 
24: vnet2:  mtu 1500 master privbr0 state forwarding priority 32 cost 100 
25: vnet3:  mtu 1500 master br0 state forwarding priority 32 cost 100 
26: vnet4:  mtu 1500 master privbr0 state forwarding priority 32 cost 100 
27: vnet5:  mtu 1500 master privbr0 state forwarding priority 32 cost 100 
28: vnet6:  mtu 1500 master virbr1 state forwarding priority 32 cost 100 
29: vnet7:  mtu 1500 master privbr0 state forwarding priority 32 cost 100 
30: vnet8:  mtu 1500 master virbr1 state forwarding priority 32 cost 100 
31: vnet9:  mtu 1500 master privbr0 state forwarding priority 32 cost 100 
32: vnet10:  mtu 1500 master privbr0 state forwarding priority 32 cost 100

4、在rh294的环境里面classroom给我们提供了两个web网站 ，分别是content.example.com和materials.example.com

5、如何操作我们的RH294环境

• 我们后面的实验练习都是通过rh294的物理操作系统连接到workstation进行操作
• workstation是我们的ansible control节点
• Servera ~ d是我们的ansible managed节点
• 几乎所有的虚拟的root密码都是redhat
• 除了root用户之外还有一个叫student的特权用户，该用户的密码是student
• classroom的root密码是Asimov

在rhel8系统，ansible会自动根据你的平台的python版本去选择

[student@workstation ~]$ yum list platform-python

如果你是rhel系统，需要使用订阅命令通过RHN镰刀红帽的软件仓库进行下载安装。
在实验环境里面，已经给我们集成了相关的软件仓库。

//安装ansible
[student@workstation ~]$ sudo yum -y install ansible

//版本信息
[student@workstation ~]$ ansible --version
ansible 2.8.0
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/student/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.6/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.6.8 (default, Apr  3 2019, 17:26:03) [GCC 8.2.1 20180905 (Red Hat 8.2.1-3)]

6、ansible安装

[student@workstation ~]$ lab intro-install start

Setting up the environment for the exercise:

 · Configuring control node packages...........................  SUCCESS

//安装ansible
[student@workstation ~]$ sudo yum -y install ansible

//查看ansible版本
[student@workstation ~]$ ansible --version
ansible 2.8.0
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/student/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.6/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.6.8 (default, Apr  3 2019, 17:26:03) [GCC 8.2.1 20180905 (Red Hat 8.2.1-3)]
 
 //ansible python module location
[student@workstation ~]$ ls /usr/lib/python3.6/site-packages/ansible
cli  compat  config  constants.py  context.py  errors  executor  galaxy  __init__.py  inventory  modules  module_utils  parsing  playbook  plugins  __pycache__  release.py  template  utils  vars

[student@workstation ~]$ lab intro-install finish

Cleaning up environment:

 . Cleaning up.................................................  SUCCESS

7、CentOS8安装Ansible

• centos上安装ansible有两种办法，一种是源码包安装，还有一种是通过epel软件仓库安装

[root@localhost ~]# yum repolist
Last metadata expiration check: 1 day, 9:21:41 ago on Sat 07 Nov 2020 12:16:13 AM EST.
repo id                                                                                                repo name                                                                                                         status
AppStream                                                                                              CentOS-8 - AppStream                                                                                              4,933
BaseOS                                                                                                 CentOS-8 - Base                                                                                                   1,673
extras                                                                                                 CentOS-8 - Extras                                                                                                    27
[root@localhost ~]# yum -y install epel8-release
Last metadata expiration check: 1 day, 9:24:55 ago on Sat 07 Nov 2020 12:16:13 AM EST.


//自动生成epel的软件仓库
[root@localhost ~]# yum -y install epel-release

[root@localhost ~]# yum repolist
Extra Packages for Enterprise Linux Modular 8 - x86_64                                                                                                                                          16 kB/s |  97 kB     00:06    
Extra Packages for Enterprise Linux 8 - x86_64                                                                                                                                                 477 kB/s | 8.3 MB     00:17    
repo id                                                                                 repo name                                                                                                                        status
AppStream                                                                               CentOS-8 - AppStream                                                                                                             4,933
BaseOS                                                                                  CentOS-8 - Base                                                                                                                  1,673
*epel                                                                                   Extra Packages for Enterprise Linux 8 - x86_64                                                                                   6,628
*epel-modular                                                                           Extra Packages for Enterprise Linux Modular 8 - x86_64                                                                               0
extras                                                                                  CentOS-8 - Extras                                                                                                                   27

//此时我们可以从epel仓库中获取到ansible安装包
[root@localhost ~]# yum list | grep ansible
ansible.noarch                                       2.9.15-1.el8                                           epel      
ansible-doc.noarch                                   2.9.15-1.el8                                           epel      
ansible-freeipa.noarch                               0.1.8-3.el8                                            AppStream 
centos-release-ansible-29.noarch                     1-2.el8                                                extras    
vim-ansible.noarch                                   3.0-1.el8                                              epel

//安装ansible
[root@localhost ~]# yum -y install ansible

//安装完成后，可以查看ansible版本
[root@localhost ~]# ansible --version
ansible 2.9.15
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/root/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.6/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.6.8 (default, May 21 2019, 23:51:36) [GCC 8.2.1 20180905 (Red Hat 8.2.1-3)]