Description of problem:

When PXE using LACP on the provisioning interface, we need to have these options enabled:
- force-up on the PXE interface.
- lacp must be set to passive.
- We need to define a native-vlan-id.
- The provisioning vlan must also be part of the vlan members.

[1] Complete config sample assuming xe-0/0/5:0 is the PXE interface, xe-0/0/5:1 it's LACP partner and 1210 is the provisioning VLAN.

[2] These are the templates used as well.

Additional info:

[1]
~~~
xe-0/0/5:0 {
    description rdu2.qfx-5200.r740-6-em1;
    ether-options {
        802.3ad {
            lacp {
                force-up;
            }
            ae60;
        }
    }
}
xe-0/0/5:1 {
    description rdu2.qfx-5200.r740-6-em2;
    ether-options {
        802.3ad ae60;
    }
}
ae60 {
    native-vlan-id 1210;
    mtu 9216;
    aggregated-ether-options {
        link-speed 10g;
        lacp {
            passive;
            periodic fast;
        }
    }
    unit 0 {
        description rdu2.qfx-5200.r740-6.p1p1-p1p2-x710;
        family ethernet-switching {
            interface-mode trunk;
            vlan {
                members [ 1210 1220 1250 1260 ];
            }
            storm-control default;
        }
    }
}
~~~

[2]
~~~
              -
                type: linux_bond
                name: bond_api
                bonding_options: "mode=802.3ad lacp_rate=fast updelay=1000 miimon=100"
                use_dhcp: false
                dns_servers:
                  get_param: DnsServers
 
                addresses:
                  -
                    ip_netmask:
                      list_join:
                        - '/'
                        - - {get_param: ControlPlaneIp}
                          - {get_param: ControlPlaneSubnetCidr}
                routes:
                  -
                    ip_netmask: 169.254.169.254/32
                    next_hop: {get_param: EC2MetadataIp}
                members:
                  -
                     type: interface
                     name: em1
                     primary: true
                  -
                     type: interface
                     name: em2
                     primary: true
              -
                type: vlan
                device: bond_api
                vlan_id: {get_param: InternalApiNetworkVlanID}
                addresses:
                  -
                    ip_netmask: {get_param: InternalApiIpSubnet}
              -
                type: vlan
                device: bond_api
                vlan_id: {get_param: StorageNetworkVlanID}
                addresses:
                  -
                    ip_netmask: {get_param: StorageIpSubnet}
~~~