Merge pull request #7884 from jprorama/fix-7171

[WIP] Fix #7171: select instance network on which to assign floating ip

builder/openstack/builder.go

@@ -129,6 +129,7 @@ func (b *Builder) Run(ctx context.Context, ui packer.Ui, hook packer.Hook) (pack
 			FloatingIPNetwork:     b.config.FloatingIPNetwork,
 			FloatingIP:            b.config.FloatingIP,
 			ReuseIPs:              b.config.ReuseIPs,
+			InstanceFloatingIPNet: b.config.InstanceFloatingIPNet,
 		},
 		&communicator.StepConnect{
 			Config: &b.config.RunConfig.Comm,

builder/openstack/networks.go

@@ -2,6 +2,7 @@ package openstack
 
 import (
 	"fmt"
+	"log"
 
 	"github.com/google/uuid"
 	"github.com/gophercloud/gophercloud"
@@ -66,7 +67,10 @@ func FindFreeFloatingIP(client *gophercloud.ServiceClient) (*floatingips.Floatin
 // GetInstancePortID returns internal port of the instance that can be used for
 // the association of a floating IP.
 // It will return an ID of a first port if there are many.
-func GetInstancePortID(client *gophercloud.ServiceClient, id string) (string, error) {
+func GetInstancePortID(client *gophercloud.ServiceClient, id string, instance_float_net string) (string, error) {
+
+	selected_interface := 0
+
 	interfacesPage, err := attachinterfaces.List(client, id).AllPages()
 	if err != nil {
 		return "", err
@@ -79,7 +83,16 @@ func GetInstancePortID(client *gophercloud.ServiceClient, id string) (string, er
 		return "", fmt.Errorf("instance '%s' has no interfaces", id)
 	}
 
-	return interfaces[0].PortID, nil
+	for i := 0; i < len(interfaces); i++ {
+		log.Printf("Instance interface: %v: %+v\n", i, interfaces[i])
+		if interfaces[i].NetID == instance_float_net {
+			log.Printf("Found preferred interface: %v\n", i)
+			selected_interface = i
+			log.Printf("Using interface value: %v", selected_interface)
+		}
+	}
+
+	return interfaces[selected_interface].PortID, nil
 }
 
 // CheckFloatingIPNetwork checks provided network reference and returns a valid

builder/openstack/run_config.go

@@ -28,6 +28,7 @@ type RunConfig struct {
 	ReuseIPs              bool              `mapstructure:"reuse_ips"`
 	SecurityGroups        []string          `mapstructure:"security_groups"`
 	Networks              []string          `mapstructure:"networks"`
+	InstanceFloatingIPNet string            `mapstructure:"instance_floating_ip_net"`
 	Ports                 []string          `mapstructure:"ports"`
 	UserData              string            `mapstructure:"user_data"`
 	UserDataFile          string            `mapstructure:"user_data_file"`

builder/openstack/step_allocate_ip.go

@@ -14,6 +14,7 @@ type StepAllocateIp struct {
 	FloatingIPNetwork     string
 	FloatingIP            string
 	ReuseIPs              bool
+	InstanceFloatingIPNet string
 }
 
 func (s *StepAllocateIp) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
@@ -114,7 +115,7 @@ func (s *StepAllocateIp) Run(ctx context.Context, state multistep.StateBag) mult
 		ui.Say(fmt.Sprintf("Associating floating IP '%s' (%s) with instance port...",
 			instanceIP.ID, instanceIP.FloatingIP))
 
-		portID, err := GetInstancePortID(computeClient, server.ID)
+		portID, err := GetInstancePortID(computeClient, server.ID, s.InstanceFloatingIPNet)
 		if err != nil {
 			err := fmt.Errorf("Error getting interfaces of the instance '%s': %s", server.ID, err)
 			state.Put("error", err)

website/source/docs/builders/openstack.html.md

@@ -155,6 +155,13 @@ builder.
 -   `insecure` (boolean) - Whether or not the connection to OpenStack can be
     done over an insecure connection. By default this is false.
 
+-   `instance_floating_ip_net` (string) - The ID of the network to which the
+    instance is attached and which should be used to associate with the floating
+    IP. This provides control over the floating ip association on multi-homed
+    instances. The association otherwise depends on a first-returned-interface
+    policy which could fail if the network to which it is connected is
+    unreachable from the floating IP network.
+
 -   `key` (string) - Client private key file path for SSL client
     authentication. If omitted the `OS_KEY` environment variable can be used.