text: 10.Reboot the VMs: 
  
  **ansible -i <inventory_file> nodes,lb -a 'reboot'**
  wrknode02.domain.example.com | UNREACHABLE! => { 
   "changed": false, 
   "msg": "SSH Error: data could not be sent to remote host 
  \"wrknode02.domain.example.com\". Make sure this host can be reached over ssh", 
   "unreachable": true 
  } 
  
  mstnode01.domain.example.com | UNREACHABLE! => { 
   "changed": false, 
   "msg": "SSH Error: data could not be sent to remote host 
  \"mstnode01.domain.example.com\". Make sure this host can be reached over ssh", 
   "unreachable": true 
  } 
  ... 
  Output truncated 
  ... 
  lbsnode01.domain.example.com | UNREACHABLE! => { 
   "changed": false, 
   "msg": "SSH Error: data could not be sent to remote host 
  \"lbsnode01.domain.example.com\". Make sure this host can be reached over ssh", 
   "unreachable": true 
  } 