diff --git a/pkg/config/transform.go b/pkg/config/transform.go
index 3abdcb16..095ff5e0 100644
--- a/pkg/config/transform.go
+++ b/pkg/config/transform.go
@@ -27,6 +27,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"strings"
 
 	"github.com/docker/go-connections/nat"
 	cliutil "github.com/rancher/k3d/v4/cmd/util" // TODO: move parseapiport to pkg
@@ -257,18 +258,27 @@ func TransformSimpleToClusterConfig(ctx context.Context, runtime runtimes.Runtim
 
 	if simpleConfig.Registries.Config != "" {
 		var k3sRegistry *k3s.Registry
-		registryConfigFile, err := os.Open(simpleConfig.Registries.Config)
-		if err != nil {
-			return nil, fmt.Errorf("Failed to open registry config file at %s: %+v", simpleConfig.Registries.Config, err)
-		}
-		configBytes, err := ioutil.ReadAll(registryConfigFile)
-		if err != nil {
-			return nil, fmt.Errorf("Failed to read registry config file at %s: %+v", registryConfigFile.Name(), err)
+
+		if strings.Contains(simpleConfig.Registries.Config, "\n") { // CASE 1: embedded registries.yaml (multiline string)
+			log.Debugf("Found multiline registries config embedded in SimpleConfig:\n%s", simpleConfig.Registries.Config)
+			if err := yaml.Unmarshal([]byte(simpleConfig.Registries.Config), &k3sRegistry); err != nil {
+				return nil, fmt.Errorf("Failed to read embedded registries config: %+v", err)
+			}
+		} else { // CASE 2: registries.yaml file referenced by path (single line)
+			registryConfigFile, err := os.Open(simpleConfig.Registries.Config)
+			if err != nil {
+				return nil, fmt.Errorf("Failed to open registry config file at %s: %+v", simpleConfig.Registries.Config, err)
+			}
+			configBytes, err := ioutil.ReadAll(registryConfigFile)
+			if err != nil {
+				return nil, fmt.Errorf("Failed to read registry config file at %s: %+v", registryConfigFile.Name(), err)
+			}
+
+			if err := yaml.Unmarshal(configBytes, &k3sRegistry); err != nil {
+				return nil, fmt.Errorf("Failed to read registry configuration: %+v", err)
+			}
 		}
 
-		if err := yaml.Unmarshal(configBytes, &k3sRegistry); err != nil {
-			return nil, fmt.Errorf("Failed to read registry configuration: %+v", err)
-		}
 		log.Tracef("Registry: read config from input:\n%+v", k3sRegistry)
 		clusterCreateOpts.Registries.Config = k3sRegistry
 	}
diff --git a/pkg/util/filter.go b/pkg/util/filter.go
index 3416e5d1..262fbf73 100644
--- a/pkg/util/filter.go
+++ b/pkg/util/filter.go
@@ -74,8 +74,9 @@ func FilterNodes(nodes []*k3d.Node, filters []string) ([]*k3d.Node, error) {
 
 		// if one of the filters is 'all', we only return this and drop all others
 		if submatches["group"] == "all" {
-			// TODO: filterNodes: only log if really more than one is specified
-			log.Warnf("Node filter 'all' set, but more were specified in '%+v'", filters)
+			if len(filters) > 1 {
+				log.Warnf("Node filter 'all' set, but more were specified in '%+v'", filters)
+			}
 			return nodes, nil
 		}
 
diff --git a/tests/assets/config_test_simple.yaml b/tests/assets/config_test_simple.yaml
index 6f98dc1f..dc8351e8 100644
--- a/tests/assets/config_test_simple.yaml
+++ b/tests/assets/config_test_simple.yaml
@@ -30,6 +30,11 @@ labels:
 registries:
   create: true
   use: []
+  config: |
+    mirrors:
+      "my.company.registry":
+        endpoint:
+          - http://my.company.registry:5000
 
 options:
   k3d:
diff --git a/tests/common.sh b/tests/common.sh
index 37fb218b..ae06586b 100755
--- a/tests/common.sh
+++ b/tests/common.sh
@@ -168,7 +168,7 @@ wait_for_pod_exec() {
 exec_in_node() {
   # $1 = container/node name
   # $2 = command
-  docker exec "$1" "$2"
+  docker exec "$1" sh -c "$2"
 }
 
 docker_assert_container_label() {
diff --git a/tests/test_config_file.sh b/tests/test_config_file.sh
index ef036348..f39f74a3 100755
--- a/tests/test_config_file.sh
+++ b/tests/test_config_file.sh
@@ -47,6 +47,11 @@ docker_assert_container_label "k3d-$clustername-server-0" "foo=bar" || failed "E
 info "Ensuring, that we have a registry node present"
 $EXE node list "k3d-$clustername-registry" || failed "Expected k3d-$clustername-registry to be present"
 
+## merged registries.yaml
+info "Ensuring, that the registries.yaml file contains both registries"
+exec_in_node "k3d-$clustername-server-0" "cat /etc/rancher/k3s/registries.yaml" | grep -i "my.company.registry"  || failed "Expected 'my.company.registry' to be in the /etc/rancher/k3s/registries.yaml"
+exec_in_node "k3d-$clustername-server-0" "cat /etc/rancher/k3s/registries.yaml" | grep -i "k3d-$clustername-registry" || failed "Expected 'k3d-$clustername-registry' to be in the /etc/rancher/k3s/registries.yaml"
+
 # Cleanup
 
 info "Deleting cluster $clustername..."