Keep DNS Nameserver Order consistency in Neutron

When a subnet has multiple DNS servers, DNS server is set up when it is created, but you can update:

Neutron subnet-update 1a2d261b-b233-3ab9-902e-88576a82afa6--dns_nameservers list=true 3.3.3.3 2.2.2.2 1.1.1.1[email protected]:~/devstack$ Neutron subnet-show 1a2d261b-b233-3ab9-902e-88576a82afa6+------------------+--------------------------------------------+| Field | Value |+------------------+--------------------------------------------+| Allocation_pools | {"Start":"10.0.0.2","End":"10.0.0.254"} || CIDR | 10.0.0.0/24 | | Dns_nameservers |                  3.3.3.3 | | |                  2.2.2.2 | | | 1.1.1.1 | | Enable_dhcp | True | | Gateway_ip | 10.0.0.1 | |                                            Host_routes | || ID | 1a2d26fb-b733-4ab3-992e-88554a87afa6 | | ip_version | 4 | |                                            name | || network_id | A404518c-800d-2353-9193-57dbb42ac5ee | | tenant_id | 3868290AB10F417390ACBB754160DBB2 |+------------------+--------------------------------------------+

Http://docs.openstack.org/developer/neutron/devref/dns_order.html

Keep DNS Nameserver Order consistency in Neutron