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##### SUMMARY
We seem to be having an issue with eos testing and AttributeError: 'NoneType' object has no attribute 'endswith'.

https://object-storage-ca-ymq-1.vexxhost.net/v1/a0b4156a37f9453eb4ec7db5422272df/ansible_79/61779/2a3bc59e39230ad945d42da08a8aad3f91dee027/third-party-check/ansible-test-network-integration-eos-python37/52a7e42/controller/ansible-debug.html#l48225

It looks like self._get_prompt() is None.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
eos_logging

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below

```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
zuul.ansible.com
```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->


##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
2019-09-04 20:16:25,014 p=zuul u=31800 | Traceback (most recent call last):
  File "/home/zuul/src/github.com/ansible/ansible/lib/ansible/utils/jsonrpc.py", line 45, in handle_request
    result = rpc_method(*args, **kwargs)
  File "/home/zuul/src/github.com/ansible/ansible/lib/ansible/plugins/connection/network_cli.py", line 389, in update_play_context
    self._terminal.on_become(passwd=auth_pass)
  File "/home/zuul/src/github.com/ansible/ansible/lib/ansible/plugins/terminal/eos.py", line 62, in on_become
    if self._get_prompt().endswith(b'#'):
AttributeError: 'NoneType' object has no attribute 'endswith'
```

- By default, Ansible will prompt the user before adding SSH keys to the
        known hosts file.  Since persistent connections such as network_cli run
        in background processes, the user will never be prompted.  By enabling
        this option, unknown host keys will automatically be added to the
        known hosts file.
      - Be sure to fully understand the security implications of enabling this
        option on production systems as it could create a security vulnerability.
    default: False
    ini:
      - section: paramiko_connection
        key: host_key_auto_add
    env:
      - name: ANSIBLE_HOST_KEY_AUTO_ADD
  persistent_connect_timeout:
    type: int
    description:
      - Configures, in seconds, the amount of time to wait when trying to
        initially establish a persistent connection.  If this value expires
        before the connection to the remote device is completed, the connection
        will fail.
    default: 30
    ini:
      - section: persistent_connection
        key: connect_timeout
    env:
      - name: ANSIBLE_PERSISTENT_CONNECT_TIMEOUT
    vars:
      - name: ansible_connect_timeout
  persistent_command_timeout:
    type: int