Adding ability to select IP version for SSH connections to OpenStack instances. Addresses #3047

builder/openstack/builder.go

@@ -102,7 +102,8 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 			Config: &b.config.RunConfig.Comm,
 			Host: CommHost(
 				computeClient,
-				b.config.SSHInterface),
+				b.config.SSHInterface,
+				b.config.SSHIPVersion),
 			SSHConfig: SSHConfig(b.config.RunConfig.Comm.SSHUsername),
 		},
 		&common.StepProvision{},

builder/openstack/run_config.go

@@ -13,6 +13,7 @@ type RunConfig struct {
 	Comm           communicator.Config `mapstructure:",squash"`
 	SSHKeyPairName string              `mapstructure:"ssh_keypair_name"`
 	SSHInterface   string              `mapstructure:"ssh_interface"`
+	SSHIPVersion   string              `mapstructure:"ssh_ip_version"`
 
 	SourceImage      string   `mapstructure:"source_image"`
 	SourceImageName  string   `mapstructure:"source_image_name"`

builder/openstack/ssh.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"log"
+	"strconv"
 	"time"
 
 	"github.com/mitchellh/multistep"
@@ -16,13 +17,14 @@ import (
 // CommHost looks up the host for the communicator.
 func CommHost(
 	client *gophercloud.ServiceClient,
-	sshinterface string) func(multistep.StateBag) (string, error) {
+	sshinterface string,
+	sshipversion string) func(multistep.StateBag) (string, error) {
 	return func(state multistep.StateBag) (string, error) {
 		s := state.Get("server").(*servers.Server)
 
 		// If we have a specific interface, try that
 		if sshinterface != "" {
-			if addr := sshAddrFromPool(s, sshinterface); addr != "" {
+			if addr := sshAddrFromPool(s, sshinterface, sshipversion); addr != "" {
 				log.Printf("[DEBUG] Using IP address %s from specified interface %s to connect", addr, sshinterface)
 				return addr, nil
 			}
@@ -41,7 +43,7 @@ func CommHost(
 		}
 
 		// Try to get it from the requested interface
-		if addr := sshAddrFromPool(s, sshinterface); addr != "" {
+		if addr := sshAddrFromPool(s, sshinterface, sshipversion); addr != "" {
 			log.Printf("[DEBUG] Using IP address %s to connect", addr)
 			return addr, nil
 		}
@@ -79,7 +81,13 @@ func SSHConfig(username string) func(multistep.StateBag) (*ssh.ClientConfig, err
 	}
 }
 
-func sshAddrFromPool(s *servers.Server, desired string) string {
+func sshAddrFromPool(s *servers.Server, desired string, sshIPVersion string) string {
+
+	ipVersion, err := strconv.Atoi(sshIPVersion)
+	if err != nil {
+		log.Printf("[ERROR] Invalid ssh IP version: %s", sshIPVersion)
+	}
+
 	// Get all the addresses associated with this server. This
 	// was taken directly from Terraform.
 	for pool, networkAddresses := range s.Addresses {
@@ -104,6 +112,14 @@ func sshAddrFromPool(s *servers.Server, desired string) string {
 			address := element.(map[string]interface{})
 			if address["OS-EXT-IPS:type"] == "floating" {
 				addr = address["addr"].(string)
+			} else if ipVersion == 4 {
+				if address["version"].(float64) == 4 {
+					addr = address["addr"].(string)
+				}
+			} else if ipVersion == 6 {
+				if address["version"].(float64) == 6 {
+					addr = fmt.Sprintf("[%s]", address["addr"].(string))
+				}
 			} else {
 				if address["version"].(float64) == 6 {
 					addr = fmt.Sprintf("[%s]", address["addr"].(string))

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

@@ -115,6 +115,8 @@ builder.
     useful for Rackspace are "public" or "private", and the default behavior is
     to connect via whichever is returned first from the OpenStack API.
 
+-   `ssh_ip_version` (string) - The IP version to use for SSH connections, valid values are `4` and `6`. Useful on dual stacked instances where the default behaviour is to connect via whichever IP address is returned first from the OpenStack API.
+
 -   `ssh_keypair_name` (string) - If specified, this is the key that will be
     used for SSH with the machine. By default, this is blank, and Packer will
     generate a temporary keypair.