實例–rescue

1. 將 lvfs1.yml 腳本的 hosts 改為 test，並存成 lvfs2.yml。
2. ansible-playbook 執行 lvfs2.yml 腳本，因 kvm12 的 vg 不足 200M，所以無法新增，所以執行 rescue 任務，列印客製化訊息 "Could not create logical volume of that size"，並改新增 100M 的 lv。

   [deyu1@kvm19 ansible]$ ansible-playbook lvfs2.yml
   
   PLAY [test] ********************************************************************
   
   TASK [Gathering Facts] *********************************************************
   ok: [kvm12]
   
   TASK [Create a logical volume of 200m] *****************************************
   fatal: [kvm12]: FAILED! => {"changed": false, "err": "  Insufficient free space: 25 
   extents needed, but only 12 available\n", "msg": "Unable to resize test to 200m", "rc": 5}
   
   TASK [debug] *******************************************************************
   ok: [kvm12] => {
       "msg": "Could not create logical volume of that size"
   }
   
   TASK [Create a logical volume of 100m] *****************************************
   changed: [kvm12]
   
   TASK [Create a ext4] ***********************************************************
   changed: [kvm12]
   
   PLAY RECAP *********************************************************************
   kvm12 : ok=4 changed=2 unreachable=0 failed=0 skipped=0 rescued=1 ignored=0
   

3. 登入 kvm12 查看 /dev/fieldwork/test 大小為 100M，且檔案格式為 ext4。

   [root@kvm12 ~]# lvdisplay /dev/fieldwork/test 
     --- Logical volume ---
     LV Path                /dev/fieldwork/test
     LV Name                test
     VG Name                fieldwork
     LV UUID                00btWc-eqJi-2Edq-e3EI-OACb-d7eP-jCbLbK
     LV Write Access        read/write
     LV Creation host, time kvm12.deyu.wang, 2020-04-01 20:13:13 +0800
     LV Status              available
     # open                 0
     LV Size                100.00 MiB
     Current LE             25
     Segments               1
     Allocation             inherit
     Read ahead sectors     auto
     - currently set to     8192
     Block device           253:2
      
   [root@kvm12 ~]# lsblk -f /dev/fieldwork/test
   NAME           FSTYPE LABEL UUID                                 MOUNTPOINT
   fieldwork-test ext4         a1ccbef7-ebd6-479c-8168-1dccb65464f5