If a parameter for a fixed IP or subnet has the string "v6" in the network role portion of the parameter name, then the following tests may fail incorrectly:

test_allowed_address_pairs_include_vm_type_network_role
test_fixed_ips_include_vm_type_network_role
test_neutron_port_fixed_ips_subnet

They each use a regex pattern like: (?P<network_role>.+[^(v6)])(_v6)?_subnet_id$

If the network role has v6 in it (ex: datav6), then this will fail.

To fix the v6 issue, the regex should likely be updated to something like: (?P<network_role>.+?)(_v6)?_subnet_id$

It also appears that the first 2 tests would also have trouble parsing the parameter correctly if either (or both) of the vm-type and network-role had an underscore in them which is allowed. This should be tested and resolved as part of this fix as well