Subnet onboard¶
The subnet onboard feature allows you to take existing subnets that have been created outside of a subnet pool and move them into an existing subnet pool. This enables you to begin using subnet pools and address scopes if you haven’t allocated existing subnets from subnet pools. It also allows you to move individual subnets between subnet pools, and by extension, move them between address scopes.
How it works¶
One of the fundamental constraints of subnet pools is that all subnets of the same address family (IPv4, IPv6) on a network must be allocated from the same subnet pool. Because of this constraint, subnets must be moved, or “onboarded”, into a subnet pool as a group at the network level rather than being handled individually. As such, the onboarding of subnets requires users to supply the UUID of the network the subnet(s) to onboard are associated with, and the UUID of the target subnet pool to perform the operation.
Does my environment support subnet onboard?¶
To test that subnet onboard is supported in your environment, execute the following command:
$ openstack extension list --network -c Alias -c Description | grep subnet_onboard
| subnet_onboard | Provides support for onboarding subnets into subnet pools
Support for subnet onboard exists in the ML2 plugin as of the Stein release. If you require subnet onboard but your current environment does not support it, consider upgrading to a release that supports subnet onboard. When using third-party plugins with neutron, check with the supplier of the plugin regarding support for subnet onboard.
Demo¶
Suppose an administrator has an existing provider network in their environment that was created without allocating its subnets from a subnet pool.
$ openstack network list
+--------------------------------------+----------------+--------------------------------------+
| ID | Name | Subnets |
+--------------------------------------+----------------+--------------------------------------+
| f643a4f5-f8d3-4325-b1fe-6061a9af0f07 | provider-net-1 | 5153cab7-7ab6-4956-8466-39aa85dccc9a |
+--------------------------------------+----------------+--------------------------------------+
$ openstack subnet show 5153cab7-7ab6-4956-8466-39aa85dccc9a
+-------------------+--------------------------------------+
| Field | Value |
+-------------------+--------------------------------------+
| allocation_pools | 192.168.0.2-192.168.7.254 |
| cidr | 192.168.0.0/21 |
| description | |
| dns_nameservers | |
| enable_dhcp | True |
| gateway_ip | 192.168.0.1 |
| host_routes | |
| id | 5153cab7-7ab6-4956-8466-39aa85dccc9a |
| ip_version | 4 |
| ipv6_address_mode | None |
| ipv6_ra_mode | None |
| network_id | f643a4f5-f8d3-4325-b1fe-6061a9af0f07 |
| prefix_length | None |
| project_id | 7b80998e5e044cee91c1cdb2e9c63afd |
| revision_number | 0 |
| segment_id | None |
| service_types | |
| subnetpool_id | None |
| tags | |
| updated_at | 2019-03-13T18:24:37Z |
+-------------------+--------------------------------------+
The administrator has created a subnet pool named routable-prefixes and
wants to onboard the subnets associated with network provider-net-1. The
administrator now wants to manage the address space for provider networks using
a subnet pool, but doesn’t have the prefixes used by these provider networks
under the management of a subnet pool or address scope.
$ openstack subnet pool list
+--------------------------------------+-------------------+--------------+
| ID | Name | Prefixes |
+--------------------------------------+-------------------+--------------+
| d05e9f61-248c-43f2-98f4-5142570127e1 | routable-prefixes | 10.10.0.0/16 |
+--------------------------------------+-------------------+--------------+
$ openstack subnet pool show routable-prefixes
+-------------------+--------------------------------+
| Field | Value |
+-------------------+--------------------------------+
| address_scope_id | None |
| created_at | 2019-03-102T05:45:01Z |
| default_prefixlen | 26 |
| default_quota | None |
| description | Routable prefixes for projects |
| headers | |
| id | d3aefb76-2527-43d4-bc21-0ec253 |
| | 908545 |
| ip_version | 4 |
| is_default | False |
| max_prefixlen | 32 |
| min_prefixlen | 8 |
| name | routable-prefixes |
| prefixes | 10.10.0.0/16 |
| project_id | cfd1889ac7d64ad891d4f20aef9f8d |
| | 7c |
| revision_number | 1 |
| shared | True |
| tags | [] |
| updated_at | 2019-03-10T05:45:01Z |
+-------------------+--------------------------------+
The administrator can use the following command to bring these subnets under the management of a subnet pool:
$ openstack network onboard subnets provider-net-1 routable-prefixes
The subnets on provider-net-1 should now all have their subnetpool_id
updated to match the UUID of the routable-prefixes subnet pool:
$ openstack subnet show 5153cab7-7ab6-4956-8466-39aa85dccc9a
+-------------------+--------------------------------------+
| Field | Value |
+-------------------+--------------------------------------+
| allocation_pools | 192.168.0.2-192.168.7.254 |
| cidr | 192.168.0.0/21 |
| description | |
| dns_nameservers | |
| enable_dhcp | True |
| gateway_ip | 192.168.0.1 |
| host_routes | |
| id | 5153cab7-7ab6-4956-8466-39aa85dccc9a |
| ip_version | 4 |
| ipv6_address_mode | None |
| ipv6_ra_mode | None |
| network_id | f643a4f5-f8d3-4325-b1fe-6061a9af0f07 |
| prefix_length | None |
| project_id | 7b80998e5e044cee91c1cdb2e9c63afd |
| revision_number | 0 |
| segment_id | None |
| service_types | |
| subnetpool_id | d3aefb76-2527-43d4-bc21-0ec253908545 |
| updated_at | 2019-03-13T18:24:37Z |
+-------------------+--------------------------------------+
The subnet pool will also now show the onboarded prefix(es) in its prefix list:
$ openstack subnet pool show routable-prefixes
+-------------------+--------------------------------+
| Field | Value |
+-------------------+--------------------------------+
| address_scope_id | None |
| created_at | 2019-03-102T05:45:01Z |
| default_prefixlen | 26 |
| default_quota | None |
| description | Routable prefixes for projects |
| headers | |
| id | d3aefb76-2527-43d4-bc21-0ec253 |
| | 908545 |
| ip_version | 4 |
| is_default | False |
| max_prefixlen | 32 |
| min_prefixlen | 8 |
| name | routable-prefixes |
| prefixes | 10.10.0.0/16, 192.168.0.0/21 |
| project_id | cfd1889ac7d64ad891d4f20aef9f8d |
| | 7c |
| revision_number | 1 |
| shared | True |
| tags | [] |
| updated_at | 2019-03-12T13:11:037Z |
+-------------------+--------------------------------+
