To Reproduce Steps to reproduce the behavior:

1. Follow the FFU doc to upgrade the environment.
2. Execute "openstack undercloud upgrade".
3. Wait execution until the error.
4. See error:

{{Exception occured while running the command
Traceback (most recent call last):
File \"/usr/lib/python3.6/site-packages/tripleoclient/command.py\", line 32, in run
super(Command, self).run(parsed_args)
File \"/usr/lib/python3.6/site-packages/osc_lib/command/command.py\", line 39, in run
return super(Command, self).run(parsed_args)
File \"/usr/lib/python3.6/site-packages/cliff/command.py\", line 186, in run
return_code = self.take_action(parsed_args) or 0
File \"/usr/lib/python3.6/site-packages/tripleoclient/v1/overcloud_node.py\", line 796, in take_action
if (len(deployed_server_port_map) > 0 and
TypeError: object of type 'NoneType' has no len()
object of type 'NoneType' has no len()}}

Expected behavior

• Undercloud upgraded

Screenshots

• Attached Image

Device Info (please complete the following information):

• OS Version: RHEL8.4
• RHOSP: 16.2.6

Bug impact

• Need to upgrade to 17.1 to keep support status

Known workaround

• Not known.

Additional context

• Upgrade fail on TASK "Run undercloud-upgrade-ephemeral-heat.py".
• At that TASK, nova container was removed from director.
• Customer have backup of undercloud.
• A scaled down compute node appears as "enroll" state and 2 ports from it was removed from environment only after few tries to upgrade undercloud. Also, looks that this node was not properly removed from overcloud.