Network Reservation

https://blueprints.launchpad.net/blazar/+spec/basic-network-plugin

This plugin supports reserving network segments.

Problem description

In OpenStack deployments with switches that support VLAN tagging, the Neutron service can create isolated network segments by associating VLAN tags with Neutron networks on a first come first serve basis. Possible VLAN tags are limited to a 12-bit field to comply with 802.1Q and, in many cases, only a small subset of the 4,096 possible VLAN tags can be made available to users. Likewise, if the cloud provider makes external Layer-2 connections (stitching) available, users can only employ these connections using a finite number of available network segments.

Use Cases

  • A user requires more network isolation for either research or additional security.

  • A user wants to make use of an external layer 2 connection and requires a VLAN tag dedicated to a provider endpoint.

  • A user plans to create an isolated VLAN and wants to make sure a VLAN tag is available at the reservation start time.

  • A cloud admin does not have enough VLAN tags to give to all users.

    • The admin wants to give a user an isolated VLAN with either host or instance reservation.

Proposed change

Blazar enables users to reserve network VLAN tags (and, by extension, other segmentation types) by specifying the physical network type the users want to reserve. Users can treat the reserved network as usual, except for the create network operation.

A basic idea for the network reservation and its scenario are as follows:

  1. The admin registers some VLAN tags used for network reservation with Blazar. The admin calls Blazar’s network API with a request body which includes the physical network name, the network type, and the segment ID.

  2. A user calls the create lease API specifying a network reservation and the start and end dates of the lease. Optional parameters would include segment ID, network name, and network type. Blazar checks the availability of a network segment for the request. If available, Blazar creates an allocation between network segment and the reservation, then returns the reservation ID. If not, Blazar doesn’t return a reservation ID.

  3. At the start time, Blazar creates the reserved network in the user’s tenant (project). The user can then create, configure, or associate subnet and router to network as usual.

  4. At the end time, Blazar deletes the network and any other associated network components such as subnets, router, ports, etc., if the user hasn’t deleted or disassociated them already.

Alternatives

None

Data model impact

The plugin introduces four new tables, “network_reservations”, “networksegment_extra_capabilities”, “network_allocations”, “network_segments”.

The “network_reservations” table keeps user request information for their network reservation. The role of this table is similar to the role of the computehost_reservations table in the host reservation plugin. This table has id, resource_properties, network_properties, network_name, network_description and network_id columns.

The “networksegment_extra_capabilities” can contain additional informations about particular network segments that a cloud provider wants to provide.

The “network_allocations” table has the relationship between the network_reservations table and the network_segments table.

The “network_segments” table stores information about network segments themselves. The reservable network segments are registered in the table.

The table definitions are as follows:

CREATE TABLE `network_reservations` (
    `created_at` datetime DEFAULT NULL,
    `updated_at` datetime DEFAULT NULL,
    `deleted_at` datetime DEFAULT NULL,
    `deleted` varchar(36) DEFAULT NULL,
    `id` varchar(36) NOT NULL,
    `reservation_id` varchar(36) DEFAULT NULL,
    `resource_properties` mediumtext,
    `network_properties` mediumtext,
    `before_end` varchar(36) DEFAULT NULL,
    `network_name` varchar(255) DEFAULT NULL,
    `network_description` varchar(255) DEFAULT NULL,
    `network_id` varchar(255) DEFAULT NULL,
    PRIMARY KEY (`id`),
    KEY `reservation_id` (`reservation_id`),
    CONSTRAINT `network_reservations_ibfk_1`
    FOREIGN KEY (`reservation_id`) REFERENCES `reservations` (`id`)
);

CREATE TABLE `network_segments` (
    `created_at` datetime DEFAULT NULL,
    `updated_at` datetime DEFAULT NULL,
    `id` varchar(36) NOT NULL,
    `network_type` varchar(255) NOT NULL,
    `physical_network` varchar(255) DEFAULT NULL,
    `segmentation_id` int(11),
    `reservable` boolean NOT NULL,
    PRIMARY KEY (`id`),
    UNIQUE KEY `network_type`
    (`network_type`,`physical_network`,`segmentation_id`)
);

CREATE TABLE `networksegment_extra_capabilities` (
    `created_at` datetime DEFAULT NULL,
    `updated_at` datetime DEFAULT NULL,
    `id` varchar(36) NOT NULL,
    `network_id` varchar(36) NOT NULL,
    `capability_name` varchar(64) NOT NULL,
    `capability_value` mediumtext NOT NULL,
    PRIMARY KEY (`id`),
    KEY `network_id` (`network_id`),
    CONSTRAINT `networksegment_extra_capabilities_ibfk_1`
    FOREIGN KEY (`network_id`) REFERENCES `network_segments` (`id`)
);


CREATE TABLE `network_allocations` (
    `created_at` datetime DEFAULT NULL,
    `updated_at` datetime DEFAULT NULL,
    `deleted_at` datetime DEFAULT NULL,
    `deleted` varchar(36) DEFAULT NULL,
    `id` varchar(36) NOT NULL,
    `network_id` varchar(36) DEFAULT NULL,
    `reservation_id` varchar(36) DEFAULT NULL,
    PRIMARY KEY (`id`),
    KEY `network_id` (`network_id`),
    KEY `reservation_id` (`reservation_id`),
    CONSTRAINT `network_allocations_ibfk_1`
    FOREIGN KEY (`network_id`) REFERENCES `network_segments` (`id`),
    CONSTRAINT `network_allocations_ibfk_2`
    FOREIGN KEY (`reservation_id`) REFERENCES `reservations` (`id`)
);

REST API impact

The network segment reservation introduces a new resource_type to the lease APIs and five new admin APIs to manage the segments.

Changes in the lease APIs

  • URL: POST /v1/leases

    • Introduced new resource_type, network, for a reservation.

Request Example:

{
  "name": "network-reservation-1",
  "reservations": [
    {
      "resource_type": "network",
      "network_name": "my-network-1",
      "physical_network": "physnet-name", # optional
      "segmentation_id": 1234,            # optional
      "network_type": "vlan"              # optional
    }
  ],
  "start_date": "2019-05-17 09:07",
  "end_date": "2019-05-17 09:10",
  "events": []
}

Response Example

{
  "lease": {
    "name": "network-reservation-1"
    "reservations": [
      {
        "id": "reservation-id",
        "status": "pending",
        "lease_id": "lease-id-1",
        "resource_id": "resource_id",
        "resource_type": "network",
        "created_at": "2019-05-17 10:00:00",
        "updated_at": "2017-05-01 11:00:00",
      }],
    "start_date": "2019-05-17 09:07",
    "end_date": "2019-05-17 09:10",
    ..snip..
  }
}
  • URL: GET /v1/leases

  • URL: GET /v1/leases/{lease-id}

  • URL: PUT /v1/leases/{lease-id}

  • URL: DELETE /v1/leases/{lease-id}

  • The change is the same as POST /v1/leases

New network APIs

The five new APIs are admin APIs by default.

  • URL: POST /v1/networks

    • The segmentation_id is a specific VLAN tag the admin wants to add. The tag must be out of allocations pools in Neutron. As of now, only networks making use of VLAN tagging require a segment id per IEEE 802.1Q. A reservable flat network would leave this field empty.

    • The network_type is the type of physical mechanism associated with the network segment. Examples include flat, geneve, gre, local, vlan, vxlan.

    • They physical_network is the name of the physical network in which the network segment is available. This is required for VLANs.

Request Example:

{
  "network_type": "vlan",
  "physical_network": "physical-network-1",
  "segmentation_id": 1234
}
  • The reservable key is a flag describing if the network segment is reservable or not. The flag is always True until the network plugin supports the resource healing feature. (Supporting resource healing to network segments is out of scope in this spec)

Response Example:

{
  "network": {
      "id": "network-id",
      "network_type": "vlan",
      "physical_network": "physical-network-1",
      "segmentation_id": 1234,
      "reservable": true,
      "created_at": "2020-01-01 10:00:00",
      "updated_at": null
  }
}
  • URL: GET /v1/networks

Response Example:

{
  "networks": [
      {
          "id": "network-id",
          "network_type": "vlan",
          "physical_network": "physical-network-1",
          "segmentation_id": 1234,
          "reservable": true,
          "created_at": "2020-01-01 10:00:00",
          "updated_at": null
      }
  ]
}
  • URL: GET /v1/networks/{network-id}

Response Example:

{
  "network": {
      "id": "network-id",
      "network_type": "vlan",
      "physical_network": "physical-network-1",
      "segmentation_id": "1234",
      "reservable": true,
      "created_at": "2020-01-01 10:00:00",
      "updated_at": null
  }
}
  • URL: DELETE /v1/networks/{network-id}

No Request body or Response body.

  • URL: PUT /v1/networks/{network-id}

    Request Example:

{
  "extra_capability_sample": "bar"
}

Response Example:

{
  "network": {
      "id": "network-id",
      "network_type": "vlan",
      "physical_network": "physical-network-1",
      "segmentation_id": "1234",
      "reservable": true,
      "created_at": "2020-01-01 10:00:00",
      "updated_at": null,
      "extra_capability_sample": "bar"
  }
}

Security impact

None

Notifications impact

None

Other end user impact

A user can reserve a network segment as well as host, instance or floating IP in the same lease.

python-blazarclient will support the network segment reservation.

Performance Impact

None

Other deployer impact

None

Developer impact

None

Upgrade impact

Some configuration options for the Neutron util class will be introduced to blazar.conf. If the cloud admin want to activate the network reservation, they will need to set up the configuration.

Implementation

Assignee(s)

Primary assignee:

priteau

Other contributors:

diurnalist jakecoll

Work Items

  • Create the new DB tables

  • Create the network reservation plugin

  • Create the network API object and its route in blazar.api.v1

  • Add network reservation support in python-blazarclient

  • Add scenario tests and API tests in blazar-tempest-plugin

  • Update Blazar docs, API reference and user guide

Dependencies

None

Testing

API tests and scenario tests need to be implemented.

Documentation Impact

This BP adds new APIs and resource type to the lease APIs. The API reference and the Blazar documentation need to be updated.

History

Revisions

Release Name

Description

Train

Introduced

Ussuri

Re-proposed