12. Create and manage networks

Before you run commands, set the following environment variables:

export OS_USERNAME=admin
export OS_PASSWORD=password
export OS_TENANT_NAME=admin
export OS_AUTH_URL=http://localhost:5000/v2.0

12.1. Create networks

List the extensions of the system:

$ neutron ext-list -c alias -c name

+-----------------+--------------------------+
| alias           | name                     |
+-----------------+--------------------------+
| agent_scheduler | Agent Schedulers         |
| binding         | Port Binding             |
| quotas          | Quota management support |
| agent           | agent                    |
| provider        | Provider Network         |
| router          | Neutron L3 Router        |
| lbaas           | LoadBalancing service    |
| extraroute      | Neutron Extra Route      |
+-----------------+--------------------------+

Create a network:

$ neutron net-create net1

Created a new network:
+---------------------------+--------------------------------------+
| Field                     | Value                                |
+---------------------------+--------------------------------------+
| admin_state_up            | True                                 |
| id                        | 2d627131-c841-4e3a-ace6-f2dd75773b6d |
| name                      | net1                                 |
| provider:network_type     | vlan                                 |
| provider:physical_network | physnet1                             |
| provider:segmentation_id  | 1001                                 |
| router:external           | False                                |
| shared                    | False                                |
| status                    | ACTIVE                               |
| subnets                   |                                      |
| tenant_id                 | 3671f46ec35e4bbca6ef92ab7975e463     |
+---------------------------+--------------------------------------+

Note

Some fields of the created network are invisible to non-admin users.

Create a network with specified provider network type:

$ neutron net-create net2 --provider:network-type local

Created a new network:
+---------------------------+--------------------------------------+
| Field                     | Value                                |
+---------------------------+--------------------------------------+
| admin_state_up            | True                                 |
| id                        | 524e26ea-fad4-4bb0-b504-1ad0dc770e7a |
| name                      | net2                                 |
| provider:network_type     | local                                |
| provider:physical_network |                                      |
| provider:segmentation_id  |                                      |
| router:external           | False                                |
| shared                    | False                                |
| status                    | ACTIVE                               |
| subnets                   |                                      |
| tenant_id                 | 3671f46ec35e4bbca6ef92ab7975e463     |
+---------------------------+--------------------------------------+

Just as shown previously, the unknown option --provider:network-type is used to create a local provider network.

12.2. Create subnets

Create a subnet:

$ neutron subnet-create net1 192.168.2.0/24 --name subnet1

Created a new subnet:
+------------------+--------------------------------------------------+
| Field            | Value                                            |
+------------------+--------------------------------------------------+
| allocation_pools | {"start": "192.168.2.2", "end": "192.168.2.254"} |
| cidr             | 192.168.2.0/24                                   |
| dns_nameservers  |                                                  |
| enable_dhcp      | True                                             |
| gateway_ip       | 192.168.2.1                                      |
| host_routes      |                                                  |
| id               | 15a09f6c-87a5-4d14-b2cf-03d97cd4b456             |
| ip_version       | 4                                                |
| name             | subnet1                                          |
| network_id       | 2d627131-c841-4e3a-ace6-f2dd75773b6d             |
| tenant_id        | 3671f46ec35e4bbca6ef92ab7975e463                 |
+------------------+--------------------------------------------------+

The subnet-create command has the following positional and optional parameters:

The name or ID of the network to which the subnet belongs.
In this example, net1 is a positional argument that specifies the network name.
The CIDR of the subnet.
In this example, 192.168.2.0/24 is a positional argument that specifies the CIDR.
The subnet name, which is optional.
In this example, --name subnet1 specifies the name of the subnet.

12.3. Create routers

Create a router:

$ neutron router-create router1

Created a new router:
+-----------------------+--------------------------------------+
| Field                 | Value                                |
+-----------------------+--------------------------------------+
| admin_state_up        | True                                 |
| external_gateway_info |                                      |
| id                    | 6e1f11ed-014b-4c16-8664-f4f615a3137a |
| name                  | router1                              |
| status                | ACTIVE                               |
| tenant_id             | 7b5970fbe7724bf9b74c245e66b92abf     |
+-----------------------+--------------------------------------+

Take note of the unique router identifier returned, this will be required in subsequent steps.

Link the router to the external provider network:
```
$ neutron router-gateway-set ROUTER NETWORK
```
Replace ROUTER with the unique identifier of the router, replace NETWORK with the unique identifier of the external provider network.
Link the router to the subnet:
```
$ neutron router-interface-add ROUTER SUBNET
```
Replace ROUTER with the unique identifier of the router, replace SUBNET with the unique identifier of the subnet.

12.4. Create ports

Create a port with specified IP address:

$ neutron port-create net1 --fixed-ip ip_address=192.168.2.40

Created a new port:
+--------------------+----------------------------------------------------------------------+
|Field               |Value                                                                 |
+--------------------+----------------------------------------------------------------------+
|admin_state_up      |True                                                                  |
|binding:capabilities|{"port_filter": false}                                                |
|binding:vif_type    |ovs                                                                   |
|device_id           |                                                                      |
|device_owner        |                                                                      |
|fixed_ips           |{"subnet_id": "15a09f6c-87a5-4d14-b2cf-03d97cd4b456", "ip_address": "192.168.2.40"}|
|id                  |f7a08fe4-e79e-4b67-bbb8-a5002455a493                                  |
|mac_address         |fa:16:3e:97:e0:fc                                                     |
|name                |                                                                      |
|network_id          |2d627131-c841-4e3a-ace6-f2dd75773b6d                                  |
|status              |DOWN                                                                  |
|tenant_id           |3671f46ec35e4bbca6ef92ab7975e463                                      |
+--------------------+----------------------------------------------------------------------+

In the previous command, net1 is the network name, which is a positional argument. --fixed-ip ip_address=192.168.2.40 is an option, which specifies the port's fixed IP address we wanted.

Note

When creating a port, you can specify any unallocated IP in the subnet even if the address is not in a pre-defined pool of allocated IP addresses (set by your cloud provider).

Create a port without specified IP address:

$ neutron port-create net1

Created a new port:
+--------------------+-----------------------------------------------------------------+
|Field               |Value                                                            |
+--------------------+-----------------------------------------------------------------+
|admin_state_up      |True                                                             |
|binding:capabilities|{"port_filter": false}                                           |
|binding:vif_type    |ovs                                                              |
|device_id           |                                                                 |
|device_owner        |                                                                 |
|fixed_ips           |{"subnet_id": "15a09f6c-87a5-4d14-b2cf-03d97cd4b456", "ip_address": "192.168.2.2"} |
|id                  |baf13412-2641-4183-9533-de8f5b91444c                             |
|mac_address         |fa:16:3e:f6:ec:c7                                                |
|name                |                                                                 |
|network_id          |2d627131-c841-4e3a-ace6-f2dd75d                                  |
|status              |DOWN                                                             |
|tenant_id           |3671f46ec35e4bbca6ef92ab7975e463                                 |
+--------------------+-----------------------------------------------------------------+

Note

Note that the system allocates one IP address if you do not specify an IP address in the neutron port-create command.

Query ports with specified fixed IP addresses:

$ neutron port-list --fixed-ips ip_address=192.168.2.2 ip_address=192.168.2.40

+--------------------------------------+------+-------------------+-------------------------------------------------------------------------------------+
| id                                   | name | mac_address       | fixed_ips                                                                           |
+--------------------------------------+------+-------------------+-------------------------------------------------------------------------------------+
| baf13412-2641-4183-9533-de8f5b91444c |      | fa:16:3e:f6:ec:c7 | {"subnet_id": "15a09f6c-87a5-4d14-b2cf-03d97cd4b456", "ip_address": "192.168.2.2"}  |
| f7a08fe4-e79e-4b67-bbb8-a5002455a493 |      | fa:16:3e:97:e0:fc | {"subnet_id": "15a09f6c-87a5-4d14-b2cf-03d97cd4b456", "ip_address": "192.168.2.40"} |
+--------------------------------------+------+-------------------+-------------------------------------------------------------------------------------+

--fixed-ips ip_address=192.168.2.2 ip_address=192.168.2.40 is one unknown option.

How to find unknown options? The unknown options can be easily found by watching the output of create_xxx or show_xxx command. For example, in the port creation command, we see the fixed_ips fields, which can be used as an unknown option.