salt.states.neutron_subnet  Management of OpenStack Neutron Subnets  New in version 2018.3.0.   depends 
shade  configuration 
see salt.modules.neutronng for setup instructions   Example States create subnet:
  neutron_subnet.present:
    - name: subnet1
    - network_name_or_id: network1
    - cidr: 639-840-3439/24


delete subnet:
  neutron_subnet.absent:
    - name: subnet2

create subnet with optional params:
  neutron_subnet.present:
    - name: subnet1
    - network_name_or_id: network1
    - enable_dhcp: True
    - cidr: 639-840-3439/24
    - allocation_pools:
      - start: 639-840-3439
        end: 639-840-3439
    - host_routes:
      - destination: 192.168..0.0/24
        nexthop: 639-840-3439
    - gateway_ip: 639-840-3439
    - dns_nameservers:
      - 639-840-3439
      - 639-840-3439

create ipv6 subnet:
  neutron_subnet.present:
    - name: v6subnet1
    - network_name_or_id: network1
    - ip_version: 6   salt.states.neutron_subnet.absent(name, auth=None) 
Ensure a subnet does not exists  name

Name of the subnet   
   salt.states.neutron_subnet.present(name, auth=None, **kwargs) 
Ensure a subnet exists and is up-to-date  name

Name of the subnet  network_name_or_id

The unique name or ID of the attached network. If a non-unique name is supplied, an exception is raised.  allocation_pools

A list of dictionaries of the start and end addresses for the allocation pools  gateway_ip

The gateway IP address.  dns_nameservers

A list of DNS name servers for the subnet.  host_routes

A list of host route dictionaries for the subnet.  ipv6_ra_mode

IPv6 Router Advertisement mode. Valid values are: ‘dhcpv6-stateful’, ‘dhcpv6-stateless’, or ‘slaac’.  ipv6_address_mode

IPv6 address mode. Valid values are: ‘dhcpv6-stateful’, ‘dhcpv6-stateless’, or ‘slaac’.   
 

    
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