Add the networks entry

builtin/providers/docker/resource_docker_container.go

@@ -238,6 +238,12 @@ func resourceDockerContainer() *schema.Resource {
 				Optional: true,
 				ForceNew: true,
 			},
+
+			"networks": &schema.Schema{
+				Type:     schema.TypeSet,
+				Optional: true,
+				ForceNew: true,
+			},
 		},
 	}
 }

builtin/providers/docker/resource_docker_container_funcs.go

@@ -148,6 +148,14 @@ func resourceDockerContainerCreate(d *schema.ResourceData, meta interface{}) err
 
 	d.SetId(retContainer.ID)
 
+	if v, ok := d.GetOk("networks"); ok {
+		connectionOpts := &dc.NetworkConnectionOptions{Container: retContainer.ID}
+
+		for _, network := range v.(*schema.Set).List() {
+			client.ConnectNetwork(network.(string), connectionOpts)
+		}
+	}
+
 	creationTime = time.Now()
 	if err := client.StartContainer(retContainer.ID, hostConfig); err != nil {
 		return fmt.Errorf("Unable to start container: %s", err)

website/source/docs/providers/docker/r/container.html.markdown

@@ -68,6 +68,7 @@ The following arguments are supported:
   Defaults to "json-file".
 * `log_opts` - (Optional) Key/value pairs to use as options for the logging
   driver.
+* `networks` - (Optional, set of strings) Id of the networks in which the container is.
 
 <a id="ports"></a>
 ## Ports