1 .. This work is licensed under a Creative Commons Attribution 4.0 International License.
2 .. http://creativecommons.org/licenses/by/4.0
4 ====================================
6 ====================================
8 https://bugs.launchpad.net/neutron/+bug/1598081
10 Neutron does not detect data plane failures affecting its logical resources.
11 This spec addresses that issue by means of allowing external tools to report to
12 Neutron about faults in the data plane that are affecting the ports. A new REST
13 API field is proposed to that end.
19 An initial description of the problem was introduced in bug #159801 [1_]. This
20 spec focuses on capturing one (main) part of the problem there described, i.e.
21 extending Neutron's REST API to cover the scenario of allowing external tools
22 to report network failures to Neutron. Out of scope of this spec are works to
23 enable port status changes to be received and managed by mechanism drivers.
25 This spec also tries to address bug #1575146 [2_]. Specifically, and argued by
26 the Neutron driver team in [3_]:
28 * Neutron should not shut down the port completly upon detection of physnet
29 failure; connectivity between instances on the same node may still be
30 reachable. Externals tools may or may not want to trigger a status change on
31 the port based on their own logic and orchestration.
33 * Port down is not detected when an uplink of a switch is down;
35 * The physnet bridge may have multiple physical interfaces plugged; shutting
36 down the logical port may not be needed in case network redundancy is in
43 A couple of possible approaches were proposed in [1_] (comment #3). This spec
44 proposes tackling the problema via a new extension API to the port resource.
45 The extension adds a new attribute 'dp-down' (data plane down) to represent the
46 status of the data plane. The field should be read-only by tenants and
49 Neutron should send out an event to the message bus upon toggling the data
50 plane status value. The event is relevant for e.g. auditing.
56 A new attribute as extension will be added to the 'ports' table.
58 +------------+-------+----------+---------+--------------------+--------------+
59 |Attribute |Type |Access |Default |Validation/ |Description |
60 |Name | | |Value |Conversion | |
61 +============+=======+==========+=========+====================+==============+
62 |dp_down |boolean|RO, tenant|False |True/False | |
63 | | |RW, admin | | | |
64 +------------+-------+----------+---------+--------------------+--------------+
70 A new API extension to the ports resource is going to be introduced.
72 .. code-block:: python
74 EXTENDED_ATTRIBUTES_2_0 = {
76 'dp_down': {'allow_post': False, 'allow_put': True,
77 'default': False, 'convert_to': convert_to_boolean,
86 Updating port data plane status to down:
90 PUT /v2.0/ports/<port-uuid>
91 Accept: application/json
100 Command Line Client Impact
101 --------------------------
105 neutron port-update [--dp-down <True/False>] <port>
106 openstack port set [--dp-down <True/False>] <port>
108 Argument --dp-down is optional. Defaults to False.
119 A notification (event) upon toggling the data plane status (i.e. 'dp-down'
120 attribute) value should be sent to the message bus. Such events do not happen
121 with high frequency and thus no negative impact on the notification bus is
134 Other Deployer Impact
135 ---------------------
155 * New 'dp-down' attribute in 'ports' database table
156 * API extension to introduce new field to port
157 * Client changes to allow for data plane status (i.e. 'dp-down' attribute')
159 * Policy (tenants read-only; admins read-write)
165 Documentation for both administrators and end users will have to be
166 contemplated. Administrators will need to know how to set/unset the data plane
173 .. [1] RFE: Port status update,
174 https://bugs.launchpad.net/neutron/+bug/1598081
176 .. [2] RFE: ovs port status should the same as physnet
177 https://bugs.launchpad.net/neutron/+bug/1575146
179 .. [3] Neutron Drivers meeting, July 21, 2016
180 http://eavesdrop.openstack.org/meetings/neutron_drivers/2016/neutron_drivers.2016-07-21-22.00.html