Unable to add NAT cloud after configuring “allowed_interfaces” in configuration file

[zccing]

After configuring “allowed_interfaces” in the configuration file, the NAT cloud cannot be added with the following error:

I recovered by modifying the judgment condition here.
I'm not sure this is the most elegant solution.

gns3-server/gns3server/compute/builtin/nodes/nat.py

Line 39 in ce4b309

if allowed_interfaces:

def __init__(self, name, node_id, project, manager, ports=None):

        allowed_interfaces = Config.instance().settings.Server.allowed_interfaces
        if allowed_interfaces and isinstance(allowed_interfaces, str):
            allowed_interfaces = allowed_interfaces.split(',')

[grossmj]

I have added your patch. Thanks again.