Open Stack

Hello,

The infra team ran into glean not being able to correctly configure host
interfaces on boot. The trigger for this appears to be this change to
nova which enabled ipv6 in metadata/config drive [0]. I don't think
there is anything wrong with this but it exposed another interesting
behavior.

The config drive network_data.json is:
{
    "links": [
        {
            "ethernet_mac_address": "fa:16:3e:9e:84:5c",
            "id": "tap14b906ba-8c",
            "mtu": 1450,
            "type": "ovs",
            "vif_id": "14b906ba-8c2c-4829-852e-2987d25ceabc"
        }
    ],
    "networks": [
        {
            "id": "network0",
            "link": "tap14b906ba-8c",
            "network_id": "7ee08c00-7323-4f18-94bb-67e081520e70",
            "type": "ipv4_dhcp"
        },
        {
            "id": "network1",
            "link": "tap14b906ba-8c",
            "network_id": "7ee08c00-7323-4f18-94bb-67e081520e70",
            "type": "ipv6_dhcp"
        }
    ],
    "services": []
}

You'll notice that the network1 entry has a type of ipv6_dhcp; however,
if you ask the neutron api it tells slaac is the ipv6_address_mode and
ipv6_ra_mode. But enable_dhcp is also set to True. So which is it? Is
there a bug here or am I missing something obvious? At the very least it
appears that the config drive info is incomplete and does not include
the slaac info.

clarkb at ubuntu-xenial-internap-mtl01-8040461:~$ openstack --os-cloud
devstack network show 7ee08c00-7323-4f18-94bb-67e081520e70
+---------------------------+----------------------------------------------------------------------------+
| Field                     | Value                                     
                                |
+---------------------------+----------------------------------------------------------------------------+
| admin_state_up            | UP                                        
                                |
| availability_zone_hints   |                                           
                                |
| availability_zones        | nova                                      
                                |
| created_at                | 2017-03-23T14:35:33Z                      
                                |
| description               |                                           
                                |
| dns_domain                | None                                      
                                |
| id                        | 7ee08c00-7323-4f18-94bb-67e081520e70      
                                |
| ipv4_address_scope        | None                                      
                                |
| ipv6_address_scope        | None                                      
                                |
| is_default                | None                                      
                                |
| mtu                       | 1450                                      
                                |
| name                      | private                                   
                                |
| port_security_enabled     | True                                      
                                |
| project_id                | 46dd6a74cf244079a4f97ba1fc493793          
                                |
| provider:network_type     | None                                      
                                |
| provider:physical_network | None                                      
                                |
| provider:segmentation_id  | None                                      
                                |
| qos_policy_id             | None                                      
                                |
| revision_number           | 7                                         
                                |
| router:external           | Internal                                  
                                |
| segments                  | None                                      
                                |
| shared                    | False                                     
                                |
| status                    | ACTIVE                                    
                                |
| subnets                   | 2cbae31d-27be-42aa-b543-b2baa5e52130,
92664772-b719-4b2d-9d47-e657be990c0b |
| updated_at                | 2017-03-23T14:35:40Z                      
                                |
+---------------------------+----------------------------------------------------------------------------+
clarkb at ubuntu-xenial-internap-mtl01-8040461:~$ openstack --os-cloud
devstack subnet show 2cbae31d-27be-42aa-b543-b2baa5e52130
+-------------------+--------------------------------------------------------+
| Field             | Value                                             
    |
+-------------------+--------------------------------------------------------+
| allocation_pools  |
fd5a:a41c:fe7a::2-fd5a:a41c:fe7a:0:ffff:ffff:ffff:ffff |
| cidr              | fd5a:a41c:fe7a::/64                               
    |
| created_at        | 2017-03-23T14:35:40Z                              
    |
| description       |                                                   
    |
| dns_nameservers   |                                                   
    |
| enable_dhcp       | True                                              
    |
| gateway_ip        | fd5a:a41c:fe7a::1                                 
    |
| host_routes       |                                                   
    |
| id                | 2cbae31d-27be-42aa-b543-b2baa5e52130              
    |
| ip_version        | 6                                                 
    |
| ipv6_address_mode | slaac                                             
    |
| ipv6_ra_mode      | slaac                                             
    |
| name              | ipv6-private-subnet                               
    |
| network_id        | 7ee08c00-7323-4f18-94bb-67e081520e70              
    |
| project_id        | 46dd6a74cf244079a4f97ba1fc493793                  
    |
| revision_number   | 2                                                 
    |
| segment_id        | None                                              
    |
| service_types     |                                                   
    |
| subnetpool_id     | eba9b529-80ce-4906-a895-ca333731afeb              
    |
| updated_at        | 2017-03-23T14:35:40Z                              
    |
+-------------------+--------------------------------------------------------+

This job is set up using a default devstack + neutron provided network
setup, then we run neutron alongside that so I don't think we are doing
anything here to affect this.

[0] https://review.openstack.org/#/c/430910/

Thanks,
Clark