GRACEFUL_DISCONNECT_WAIT_SEC does not work

[rasmus.elmholt]

Hi all

I have a small script that collects information from a list of devices, but it takes a long time.

I have found out that there is a disconnection time of 10s I think I am hitting.

I have found the documentation that says I can change the settings but when I test it out there is still a delay after the disconnect.

def atswrapper_bfd(dev_ip, cli_username, cli_password):
    atsbfd = None
    testbed = loader.load(
        {
            "devices": {
                device["name"]: {
                    "connections": {
                        "cli": {
                            "protocol": "ssh",
                            "ip": dev_ip,
                            "init_exec_commands": [],
                            "init_config_commands": []
                        },
                        "settings": {
                            "GRACEFUL_DISCONNECT_WAIT_SEC": 1,
                            "POST_DISCONNECT_WAIT_SEC": 1
                        }
                    }, # Find a better way to do this: https://github.com/CiscoTestAutomation/genielibs/issues/12
                    "credentials": {
                        "default": {
                            "username": cli_username,
                            "password": cli_password,
                        }
                    },
                    "type": "Device",
                    "os": "iosxe"
                }
            }
        }
    )
    atsdevice = testbed.devices[device["name"]]
    atsdevice.connect(via='cli', log_stdout=True, learn_hostname=True, connection_timeout=2)

    atsbfd = atsdevice.parse('show bfd neighbors details')
    atsdevice.disconnect()
    return atsbfd

[bigevilbeard]

Hmm... from what you describe, it seems that the 10-second delay you are see is not directly related to GRACEFUL_DISCONNECT_WAIT_SEC / POST_DISCONNECT_WAIT_SEC settings. It might be caused by a combination a few things such as network latency, connection timeouts, or device-specific limitations. I am also unsure if the genielibs library might have additional logic for disconnection that overrides your settings too (guessing here)?

[rasmus.elmholt]

Hi @bigevilbeard 

When I look at the logs it gives from log_stdout=True it completes the show command, hangs for 10 seconds and then continue.

I have tried to add the following lines and then the function is a lot faster.

atsdevice = testbed.devices[device["name"]]
    atsdevice.connect(via='cli', log_stdout=True, learn_hostname=True, connection_timeout=2)

    atsdevice.settings.GRACEFUL_DISCONNECT_WAIT_SEC = 0
    atsdevice.settings.POST_DISCONNECT_WAIT_SEC  = 0

    atsbfd = atsdevice.parse('show bfd neighbors details')
    atsdevice.disconnect()

But I still cannot get it to work when using the dictionary with configuration. 

[bigevilbeard]

Not sure if this would work, but try this idea below, the GRACEFUL_DISCONNECT_WAIT_SEC and POST_DISCONNECT_WAIT_SEC settings are now set within the settings key of the device dictionary, it _should_ correctly set the values and reduce the delay between sending the show command and disconnecting from the device. (I hope!)

def atswrapper_bfd(dev_ip, cli_username, cli_password):
    atsbfd = None
    testbed = loader.load(
        {
            "devices": {
                device["name"]: {
                    "connections": {
                        "cli": {
                            "protocol": "ssh",
                            "ip": dev_ip,
                            "init_exec_commands": [],
                            "init_config_commands": []
                        }
                    },
                    "credentials": {
                        "default": {
                            "username": cli_username,
                            "password": cli_password,
                        }
                    },
                    "type": "Device",
                    "os": "iosxe",
                    "settings": {
                        "GRACEFUL_DISCONNECT_WAIT_SEC": 0,
                        "POST_DISCONNECT_WAIT_SEC": 0
                    }
                }
            }
        }
    )
    atsdevice = testbed.devices[device["name"]]
    atsdevice.connect(via='cli', log_stdout=True, learn_hostname=True, connection_timeout=2)

    atsbfd = atsdevice.parse('show bfd neighbors details')
    atsdevice.disconnect()
    return atsbfd