### General Description ###
There is a “Proposed Change” regarding “QoS DSCP marking support” as it documented in:
http://specs.openstack.org/openstack/neutron-specs/specs/newton/ml2-qos-with-dscp.html
We propose an update to the QoS API and OVS driver to support DSCP marks. Valid DSCP mark values can be between 0 and 56, except 2-6, 42, 44, and 50-54.
### Test scenario ###
1) ssh to your Undercloud host
2) switch to “stack” user with: “su – stack“
3) Source overcloudrc file with: “source overcloudrc”
4) Upload the attached “Check_DSCP_Options.py” Python script (inside the attached *.zip) to your home directory (stack home) and run it with “python Check_DSCP_Options.py” command while monitoring “server.log” on your controller node.
### Expected Result ###
Valid DSCP mark values can be between 0 and 56, except 2-6, 42, 44, and 50-54.
### Actual Result ###
1) Failed DSCP mark IDs:
[1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 42, 43, 44, 45, 47, 49, 50, 51, 52, 53, 54, 55]
2) As you can see we do have supported and not DSCP Mark IDs, but it has different behavior than expected.
3) You can find the controller “server.log” attached (inside attached *.zip) and you can see there messages like this one:
2018-07-02 15:04:58.535 28 INFO neutron.api.v2.resource [req-74bb7060-b9b2-4542-bd8a-d805a8ff079c b4332e1592ab480f96fc87e5af797895 f3f03848a45746c7bcbe95b625d7e1d8 - default default] update failed (client error): Invalid input for dscp_mark. Reason: 55 is not in valid_values.
for all mentioned IDs:
[ashtempl@ashtempl ~]$ grep -i 'is not in' server.log | cut -d ':' -f5
1 is not in valid_values.
2 is not in valid_values.
3 is not in valid_values.
4 is not in valid_values.
5 is not in valid_values.
6 is not in valid_values.
7 is not in valid_values.
9 is not in valid_values.
11 is not in valid_values
13 is not in valid_values.
15 is not in valid_values.
17 is not in valid_values.
19 is not in valid_values.
21 is not in valid_values.
23 is not in valid_values.
25 is not in valid_values.
27 is not in valid_values.
29 is not in valid_values.
31 is not in valid_values.
33 is not in valid_values.
35 is not in valid_values.
37 is not in valid_values.
39 is not in valid_values.
41 is not in valid_values.
42 is not in valid_values.
43 is not in valid_values.
44 is not in valid_values.
45 is not in valid_values.
47 is not in valid_values.
49 is not in valid_values.
50 is not in valid_values.
51 is not in valid_values.
52 is not in valid_values.
53 is not in valid_values.
54 is not in valid_values.
55 is not in valid_values.
Fix proposed to branch: master
Review: https:/