Add k3d- prefix to docker network name

Should make sense since all container names are with the same prefix.

cli/container.go

@@ -105,7 +105,7 @@ func createServer(verbose bool, image string, apiPort string, args []string, env
 
 	networkingConfig := &network.NetworkingConfig{
 		EndpointsConfig: map[string]*network.EndpointSettings{
-			name: {
+			k3dNetworkName(name): {
 				Aliases: []string{containerName},
 			},
 		},
@@ -175,7 +175,7 @@ func createWorker(verbose bool, image string, args []string, env []string, name
 
 	networkingConfig := &network.NetworkingConfig{
 		EndpointsConfig: map[string]*network.EndpointSettings{
-			name: {
+			k3dNetworkName(name): {
 				Aliases: []string{containerName},
 			},
 		},

cli/network.go

@@ -10,6 +10,10 @@ import (
 	"github.com/docker/docker/client"
 )
 
+func k3dNetworkName(clusterName string) string {
+	return fmt.Sprintf("k3d-%s", clusterName)
+}
+
 // createClusterNetwork creates a docker network for a cluster that will be used
 // to let the server and worker containers communicate with each other easily.
 func createClusterNetwork(clusterName string) (string, error) {
@@ -36,7 +40,7 @@ func createClusterNetwork(clusterName string) (string, error) {
 	}
 
 	// create the network with a set of labels and the cluster name as network name
-	resp, err := docker.NetworkCreate(ctx, clusterName, types.NetworkCreate{
+	resp, err := docker.NetworkCreate(ctx, k3dNetworkName(clusterName), types.NetworkCreate{
 		Labels: map[string]string{
 			"app":     "k3d",
 			"cluster": clusterName,