實例–正常任務

1. 腳本 lvfs1.yml 使用 block - rescue - always 語法
   1. when: 限定只有 fieldwork vg 存在時才執行。
   2. 在 fieldwork 新增一個名為 test，大小 200M 的 lv
   3. rescue: 如果無法新增就改新增 100M 的 lv，且印出 "Could not create logical volume of that size"。
   4. always: 新增後將其格式化為 ext4。

   [deyu1@kvm19 ansible]$ vim lvfs1.yml 
   [deyu1@kvm19 ansible]$ cat lvfs1.yml 
   ---
   - hosts: dev 
     tasks:
     - block:
       - name: Create a logical volume of 200m
         lvol:
           vg: fieldwork
           lv: test
           size: '200'
     
       rescue:
       - debug:
           msg: Could not create logical volume of that size
       - name: Create a logical volume of 100m
         lvol:
           vg: fieldwork
           lv: test
           size: '100'
   
       always:
       - name: Create a ext4
         filesystem:
           fstype: ext4
           dev: /dev/fieldwork/test
    
       when: ansible_lvm.vgs.fieldwork is defined
   

2. ansible-playbook 執行 lvfs1.yml 腳本，正常新增 200M lv test，且成功格式化。

   [deyu1@kvm19 ansible]$ ansible-playbook lvfs1.yml
   
   PLAY [dev] *********************************************************************
   
   TASK [Gathering Facts] *********************************************************
   ok: [kvm11]
   
   TASK [Create a logical volume of 200m] *****************************************
   changed: [kvm11]
   
   TASK [Create a ext4] ***********************************************************
   changed: [kvm11]
   
   PLAY RECAP *********************************************************************
   kvm11 : ok=3 changed=2 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
   

3. 登入 kvm11 查看 /dev/fieldwork/test 大小為 200M，且檔案格式為 ext4。

   [root@kvm11 ~]# lvdisplay /dev/fieldwork/test
     --- Logical volume ---
     LV Path                /dev/fieldwork/test
     LV Name                test
     VG Name                fieldwork
     LV UUID                LCXmQs-ZCJb-S5XF-rKWU-ZqB5-1EHD-m5TViN
     LV Write Access        read/write
     LV Creation host, time kvm11.deyu.wang, 2020-04-01 19:21:13 +0800
     LV Status              available
     # open                 0
     LV Size                200.00 MiB
     Current LE             50
     Segments               1
     Allocation             inherit
     Read ahead sectors     auto
     - currently set to     8192
     Block device           253:2
   
   [root@kvm11 ~]# lsblk -f /dev/fieldwork/test
   NAME           FSTYPE LABEL UUID                                 MOUNTPOINT
   fieldwork-test ext4         f2bbe681-5832-4d4e-8765-9cd0ea1f2bee