##### SUMMARY
Currently there is some issue with the reboot module with OpenVZ hosts. The reboot command is executed correctly, all hosts reboots, but the Ansible reboot tasks hangs.

If exactly the same playbook is run on KVM or native host, it finish without any issues.

It should be hot fixed in 2.7+ branches.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
reboot module

##### ANSIBLE VERSION
2.7

##### CONFIGURATION
Debian 9.9 / Ansible 2.8

##### OS / ENVIRONMENT
Debian 9.9


##### STEPS TO REPRODUCE
Trigger this reboot handler on OpenVZ hosts
```
- name: Reboot system
  reboot:
    reboot_timeout: 1200
    post_reboot_delay: 5
    connect_timeout: 2
  listen: handler_reboot
```

##### EXPECTED RESULTS
Reboot is executed and once the host is back online, task is marked as changed and the execution of the playbook continues.


##### ACTUAL RESULTS
```
...
RUNNING HANDLER [shared_handlers : Reboot system] ********
```
(and no more output, the Ansible playbook hangs)
- Seconds to wait after the reboot command was successful before attempting to validate the system rebooted successfully.
    - This is useful if you want wait for something to settle despite your connection already working.
    type: int
    default: 0
    version_added: '2.4'
    aliases: [ post_reboot_delay_sec ]
  shutdown_timeout:
    description:
    - Maximum seconds to wait for shutdown to occur.
    - Increase this timeout for very slow hardware, large update applications, etc.
    - This option has been removed since Ansible 2.5 as the win_reboot behavior has changed.
    type: int
    default: 600
    aliases: [ shutdown_timeout_sec ]
  reboot_timeout:
    description:
    - Maximum seconds to wait for machine to re-appear on the network and respond to a test command.
    - This timeout is evaluated separately for both reboot verification and test command success so maximum clock time is actually twice this value.
    type: int
    default: 600
    aliases: [ reboot_timeout_sec ]
  connect_timeout:
    description:
    - Maximum seconds to wait for a single successful TCP connection to the WinRM endpoint before trying again.
    type: int
    default: 5
    aliases: [ connect_timeout_sec ]
  test_command:
    description:
    - Command to expect success for to determine the machine is ready for management.