Merge pull request #9634 from dmcgowan/add-migration-tests

Add migration tests

cmd/containerd/command/config.go

@@ -123,6 +123,28 @@ var configCommand = cli.Command{
 					}
 				}
 
+				plugins, err := server.LoadPlugins(ctx, config)
+				if err != nil {
+					return err
+				}
+				if len(plugins) != 0 {
+					if config.Plugins == nil {
+						config.Plugins = make(map[string]interface{})
+					}
+					for _, p := range plugins {
+						if p.Config == nil {
+							continue
+						}
+
+						pc, err := config.Decode(ctx, p.URI(), p.Config)
+						if err != nil {
+							return err
+						}
+
+						config.Plugins[p.URI()] = pc
+					}
+				}
+
 				config.Version = srvconfig.CurrentConfigVersion
 
 				return toml.NewEncoder(os.Stdout).SetIndentTables(true).Encode(config)

cmd/containerd/server/config/config.go

@@ -30,6 +30,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"reflect"
 	"strings"
 
 	"dario.cat/mergo"
@@ -310,12 +311,6 @@ func LoadConfig(ctx context.Context, path string, out *Config) error {
 		pending = append(pending, imports...)
 	}
 
-	// Fix up the list of config files loaded
-	out.Imports = []string{}
-	for path := range loaded {
-		out.Imports = append(out.Imports, path)
-	}
-
 	err := out.ValidateVersion()
 	if err != nil {
 		return fmt.Errorf("failed to load TOML from %s: %w", path, err)
@@ -408,9 +403,11 @@ func resolveImports(parent string, imports []string) ([]string, error) {
 // 0            1           1
 // []{"1"}      []{"2"}     []{"1","2"}
 // []{"1"}      []{}        []{"1"}
+// []{"1", "2"} []{"1"}     []{"1","2"}
+// []{}         []{"2"}     []{"2"}
 // Maps merged by keys, but values are replaced entirely.
 func mergeConfig(to, from *Config) error {
-	err := mergo.Merge(to, from, mergo.WithOverride, mergo.WithAppendSlice)
+	err := mergo.Merge(to, from, mergo.WithOverride, mergo.WithTransformers(sliceTransformer{}))
 	if err != nil {
 		return err
 	}
@@ -435,6 +432,43 @@ func mergeConfig(to, from *Config) error {
 	return nil
 }
 
+type sliceTransformer struct{}
+
+func (sliceTransformer) Transformer(t reflect.Type) func(dst, src reflect.Value) error {
+	if t.Kind() != reflect.Slice {
+		return nil
+	}
+	return func(dst, src reflect.Value) error {
+		if !dst.CanSet() {
+			return nil
+		}
+		if src.Type() != dst.Type() {
+			return fmt.Errorf("cannot append two slice with different type (%s, %s)", src.Type(), dst.Type())
+		}
+		for i := 0; i < src.Len(); i++ {
+			found := false
+			for j := 0; j < dst.Len(); j++ {
+				srcv := src.Index(i)
+				dstv := dst.Index(j)
+				if !srcv.CanInterface() || !dstv.CanInterface() {
+					if srcv.Equal(dstv) {
+						found = true
+						break
+					}
+				} else if reflect.DeepEqual(srcv.Interface(), dstv.Interface()) {
+					found = true
+					break
+				}
+			}
+			if !found {
+				dst.Set(reflect.Append(dst, src.Index(i)))
+			}
+		}
+
+		return nil
+	}
+}
+
 // V2DisabledFilter matches based on URI
 func V2DisabledFilter(list []string) plugin.DisableFilter {
 	set := make(map[string]struct{}, len(list))

cmd/containerd/server/config/config_test.go

@@ -50,6 +50,7 @@ func TestMergeConfigs(t *testing.T) {
 		Version:          2,
 		Root:             "new_root",
 		RequiredPlugins:  []string{"io.containerd.new_plugin1.v1", "io.containerd.new_plugin2.v1"},
+		DisabledPlugins:  []string{"io.containerd.old_plugin.v1"},
 		OOMScore:         2,
 		Timeouts:         map[string]string{"b": "2"},
 		StreamProcessors: map[string]StreamProcessor{"1": {Path: "3"}},
@@ -191,8 +192,8 @@ imports = ["data1.toml", "data2.toml"]
 
 	sort.Strings(out.Imports)
 	assert.Equal(t, []string{
-		filepath.Join(tempDir, "data1.toml"),
+		"data1.toml",
-		filepath.Join(tempDir, "data2.toml"),
+		"data2.toml",
 	}, out.Imports)
 }
 

integration/client/migration_test.go

@@ -0,0 +1,92 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package client
+
+import (
+	"bytes"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMigration(t *testing.T) {
+	currentDefault := filepath.Join(t.TempDir(), "default.toml")
+	defaultContent, err := currentDefaultConfig()
+	require.NoError(t, err)
+	require.NoError(t, os.WriteFile(currentDefault, []byte(defaultContent), 0644))
+
+	type migrationTest struct {
+		Name     string
+		File     string
+		Migrated string
+	}
+	migrationTests := []migrationTest{
+		{
+			Name:     "CurrentDefault",
+			File:     currentDefault,
+			Migrated: defaultContent,
+		},
+	}
+
+	// Only run the old version migration tests for the same platform
+	// and build settings the default config was generated for.
+	if runtime.GOOS == "linux" && runtime.GOARCH == "amd64" && strings.Contains(defaultContent, "btrfs") && strings.Contains(defaultContent, "devmapper") {
+		migrationTests = append(migrationTests, []migrationTest{
+			{
+				Name:     "1.6-Default",
+				File:     "testdata/default-1.6.toml",
+				Migrated: defaultContent,
+			},
+			{
+				Name:     "1.7-Default",
+				File:     "testdata/default-1.7.toml",
+				Migrated: defaultContent,
+			},
+		}...)
+	}
+
+	for _, tc := range migrationTests {
+		tc := tc
+		t.Run(tc.Name, func(t *testing.T) {
+			buf := bytes.NewBuffer(nil)
+			cmd := exec.Command("containerd", "-c", tc.File, "config", "migrate")
+			cmd.Stdout = buf
+			cmd.Stderr = os.Stderr
+			require.NoError(t, cmd.Run())
+			actual := buf.String()
+			assert.Equal(t, tc.Migrated, actual)
+		})
+	}
+
+}
+
+func currentDefaultConfig() (string, error) {
+	cmd := exec.Command("containerd", "config", "default")
+	buf := bytes.NewBuffer(nil)
+	cmd.Stdout = buf
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		return "", err
+	}
+	return buf.String(), nil
+}

integration/client/testdata/default-1.6.toml

@@ -0,0 +1,263 @@
+disabled_plugins = []
+imports = []
+oom_score = 0
+plugin_dir = ""
+required_plugins = []
+root = "/var/lib/containerd"
+state = "/run/containerd"
+temp = ""
+version = 2
+
+[cgroup]
+  path = ""
+
+[debug]
+  address = ""
+  format = ""
+  gid = 0
+  level = ""
+  uid = 0
+
+[grpc]
+  address = "/run/containerd/containerd.sock"
+  gid = 0
+  max_recv_message_size = 16777216
+  max_send_message_size = 16777216
+  tcp_address = ""
+  tcp_tls_ca = ""
+  tcp_tls_cert = ""
+  tcp_tls_key = ""
+  uid = 0
+
+[metrics]
+  address = ""
+  grpc_histogram = false
+
+[plugins]
+
+  [plugins."io.containerd.gc.v1.scheduler"]
+    deletion_threshold = 0
+    mutation_threshold = 100
+    pause_threshold = 0.02
+    schedule_delay = "0s"
+    startup_delay = "100ms"
+
+  [plugins."io.containerd.grpc.v1.cri"]
+    device_ownership_from_security_context = false
+    disable_apparmor = false
+    disable_cgroup = false
+    disable_hugetlb_controller = true
+    disable_proc_mount = false
+    disable_tcp_service = true
+    enable_selinux = false
+    enable_tls_streaming = false
+    # Defaults change to true in latest
+    #enable_unprivileged_icmp = false
+    #enable_unprivileged_ports = false
+    enable_unprivileged_icmp = true
+    enable_unprivileged_ports = true
+    ignore_image_defined_volumes = false
+    max_concurrent_downloads = 3
+    max_container_log_line_size = 16384
+    netns_mounts_under_state_dir = false
+    restrict_oom_score_adj = false
+    # Default image update in latest
+    #sandbox_image = "registry.k8s.io/pause:3.6"
+    sandbox_image = "registry.k8s.io/pause:3.9"
+    selinux_category_range = 1024
+    stats_collect_period = 10
+    stream_idle_timeout = "4h0m0s"
+    stream_server_address = "127.0.0.1"
+    stream_server_port = "0"
+    systemd_cgroup = false
+    tolerate_missing_hugetlb_controller = true
+    unset_seccomp_profile = ""
+
+    [plugins."io.containerd.grpc.v1.cri".cni]
+      bin_dir = "/opt/cni/bin"
+      conf_dir = "/etc/cni/net.d"
+      conf_template = ""
+      ip_pref = ""
+      max_conf_num = 1
+
+    [plugins."io.containerd.grpc.v1.cri".containerd]
+      default_runtime_name = "runc"
+      disable_snapshot_annotations = true
+      discard_unpacked_layers = false
+      ignore_rdt_not_enabled_errors = false
+      no_pivot = false
+      snapshotter = "overlayfs"
+
+      [plugins."io.containerd.grpc.v1.cri".containerd.default_runtime]
+        base_runtime_spec = ""
+        cni_conf_dir = ""
+        cni_max_conf_num = 0
+        container_annotations = []
+        pod_annotations = []
+        privileged_without_host_devices = false
+        runtime_engine = ""
+        runtime_path = ""
+        runtime_root = ""
+        runtime_type = ""
+
+        [plugins."io.containerd.grpc.v1.cri".containerd.default_runtime.options]
+
+      [plugins."io.containerd.grpc.v1.cri".containerd.runtimes]
+
+        [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
+          base_runtime_spec = ""
+          cni_conf_dir = ""
+          cni_max_conf_num = 0
+          container_annotations = []
+          pod_annotations = []
+          privileged_without_host_devices = false
+          runtime_engine = ""
+          runtime_path = ""
+          runtime_root = ""
+          runtime_type = "io.containerd.runc.v2"
+
+          [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
+            BinaryName = ""
+            CriuImagePath = ""
+            CriuWorkPath = ""
+            IoGid = 0
+            IoUid = 0
+            NoNewKeyring = false
+            Root = ""
+            ShimCgroup = ""
+            # Removed in latest
+            #CriuPath = ""
+            #NoPivotRoot = false
+            #SystemdCgroup = false
+
+      [plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime]
+        base_runtime_spec = ""
+        cni_conf_dir = ""
+        cni_max_conf_num = 0
+        container_annotations = []
+        pod_annotations = []
+        privileged_without_host_devices = false
+        runtime_engine = ""
+        runtime_path = ""
+        runtime_root = ""
+        runtime_type = ""
+
+        [plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime.options]
+
+    [plugins."io.containerd.grpc.v1.cri".image_decryption]
+      key_model = "node"
+
+    [plugins."io.containerd.grpc.v1.cri".registry]
+      config_path = ""
+
+      [plugins."io.containerd.grpc.v1.cri".registry.auths]
+
+      [plugins."io.containerd.grpc.v1.cri".registry.configs]
+
+      [plugins."io.containerd.grpc.v1.cri".registry.headers]
+
+      [plugins."io.containerd.grpc.v1.cri".registry.mirrors]
+
+    [plugins."io.containerd.grpc.v1.cri".x509_key_pair_streaming]
+      tls_cert_file = ""
+      tls_key_file = ""
+
+  [plugins."io.containerd.internal.v1.opt"]
+    path = "/opt/containerd"
+
+  [plugins."io.containerd.internal.v1.restart"]
+    interval = "10s"
+
+  [plugins."io.containerd.internal.v1.tracing"]
+    sampling_ratio = 1.0
+    service_name = "containerd"
+
+  [plugins."io.containerd.metadata.v1.bolt"]
+    content_sharing_policy = "shared"
+
+  [plugins."io.containerd.monitor.v1.cgroups"]
+    no_prometheus = false
+
+  # Removed in latest
+  #[plugins."io.containerd.runtime.v1.linux"]
+  #  no_shim = false
+  #  runtime = "runc"
+  #  runtime_root = ""
+  #  shim = "containerd-shim"
+  #  shim_debug = false
+
+  [plugins."io.containerd.runtime.v2.task"]
+    platforms = ["linux/amd64"]
+    sched_core = false
+
+  [plugins."io.containerd.service.v1.diff-service"]
+    default = ["walking"]
+
+  [plugins."io.containerd.service.v1.tasks-service"]
+    rdt_config_file = ""
+
+  # Removed in latest
+  #[plugins."io.containerd.snapshotter.v1.aufs"]
+  #  root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.btrfs"]
+    root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.devmapper"]
+    async_remove = false
+    base_image_size = ""
+    discard_blocks = false
+    fs_options = ""
+    fs_type = ""
+    pool_name = ""
+    root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.native"]
+    root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.overlayfs"]
+    mount_options = []
+    root_path = ""
+    sync_remove = false
+    upperdir_label = false
+
+  # Removed in latest
+  #[plugins."io.containerd.snapshotter.v1.zfs"]
+  #  root_path = ""
+
+  [plugins."io.containerd.tracing.processor.v1.otlp"]
+    endpoint = ""
+    insecure = false
+    protocol = ""
+
+[proxy_plugins]
+
+[stream_processors]
+
+  [stream_processors."io.containerd.ocicrypt.decoder.v1.tar"]
+    accepts = ["application/vnd.oci.image.layer.v1.tar+encrypted"]
+    args = ["--decryption-keys-path", "/etc/containerd/ocicrypt/keys"]
+    env = ["OCICRYPT_KEYPROVIDER_CONFIG=/etc/containerd/ocicrypt/ocicrypt_keyprovider.conf"]
+    path = "ctd-decoder"
+    returns = "application/vnd.oci.image.layer.v1.tar"
+
+  [stream_processors."io.containerd.ocicrypt.decoder.v1.tar.gzip"]
+    accepts = ["application/vnd.oci.image.layer.v1.tar+gzip+encrypted"]
+    args = ["--decryption-keys-path", "/etc/containerd/ocicrypt/keys"]
+    env = ["OCICRYPT_KEYPROVIDER_CONFIG=/etc/containerd/ocicrypt/ocicrypt_keyprovider.conf"]
+    path = "ctd-decoder"
+    returns = "application/vnd.oci.image.layer.v1.tar+gzip"
+
+[timeouts]
+  "io.containerd.timeout.bolt.open" = "0s"
+  "io.containerd.timeout.shim.cleanup" = "5s"
+  "io.containerd.timeout.shim.load" = "5s"
+  "io.containerd.timeout.shim.shutdown" = "3s"
+  "io.containerd.timeout.task.state" = "2s"
+  # Added in latest
+  "io.containerd.timeout.metrics.shimstats" = "2s"
+
+[ttrpc]
+  address = ""
+  gid = 0
+  uid = 0

integration/client/testdata/default-1.7.toml

@@ -0,0 +1,306 @@
+disabled_plugins = []
+imports = []
+oom_score = 0
+plugin_dir = ""
+required_plugins = []
+root = "/var/lib/containerd"
+state = "/run/containerd"
+temp = ""
+version = 2
+
+[cgroup]
+  path = ""
+
+[debug]
+  address = ""
+  format = ""
+  gid = 0
+  level = ""
+  uid = 0
+
+[grpc]
+  address = "/run/containerd/containerd.sock"
+  gid = 0
+  max_recv_message_size = 16777216
+  max_send_message_size = 16777216
+  tcp_address = ""
+  tcp_tls_ca = ""
+  tcp_tls_cert = ""
+  tcp_tls_key = ""
+  uid = 0
+
+[metrics]
+  address = ""
+  grpc_histogram = false
+
+[plugins]
+
+  [plugins."io.containerd.gc.v1.scheduler"]
+    deletion_threshold = 0
+    mutation_threshold = 100
+    pause_threshold = 0.02
+    schedule_delay = "0s"
+    startup_delay = "100ms"
+
+  [plugins."io.containerd.grpc.v1.cri"]
+    cdi_spec_dirs = ["/etc/cdi", "/var/run/cdi"]
+    device_ownership_from_security_context = false
+    disable_apparmor = false
+    disable_cgroup = false
+    disable_hugetlb_controller = true
+    disable_proc_mount = false
+    disable_tcp_service = true
+    drain_exec_sync_io_timeout = "0s"
+    # Updated in latest release
+    #enable_cdi = false
+    enable_cdi = true
+    enable_selinux = false
+    enable_tls_streaming = false
+    # Updated in latest release
+    #enable_unprivileged_icmp = false
+    #enable_unprivileged_ports = false
+    enable_unprivileged_icmp = true
+    enable_unprivileged_ports = true
+    ignore_image_defined_volumes = false
+    image_pull_progress_timeout = "5m0s"
+    max_concurrent_downloads = 3
+    max_container_log_line_size = 16384
+    netns_mounts_under_state_dir = false
+    restrict_oom_score_adj = false
+    # Updated in latest
+    #sandbox_image = "registry.k8s.io/pause:3.8"
+    sandbox_image = "registry.k8s.io/pause:3.9"
+    selinux_category_range = 1024
+    stats_collect_period = 10
+    stream_idle_timeout = "4h0m0s"
+    stream_server_address = "127.0.0.1"
+    stream_server_port = "0"
+    systemd_cgroup = false
+    tolerate_missing_hugetlb_controller = true
+    unset_seccomp_profile = ""
+
+    [plugins."io.containerd.grpc.v1.cri".cni]
+      bin_dir = "/opt/cni/bin"
+      conf_dir = "/etc/cni/net.d"
+      conf_template = ""
+      ip_pref = ""
+      max_conf_num = 1
+      setup_serially = false
+
+    [plugins."io.containerd.grpc.v1.cri".containerd]
+      default_runtime_name = "runc"
+      disable_snapshot_annotations = true
+      discard_unpacked_layers = false
+      ignore_blockio_not_enabled_errors = false
+      ignore_rdt_not_enabled_errors = false
+      no_pivot = false
+      snapshotter = "overlayfs"
+
+      [plugins."io.containerd.grpc.v1.cri".containerd.default_runtime]
+        base_runtime_spec = ""
+        cni_conf_dir = ""
+        cni_max_conf_num = 0
+        container_annotations = []
+        pod_annotations = []
+        privileged_without_host_devices = false
+        privileged_without_host_devices_all_devices_allowed = false
+        runtime_engine = ""
+        runtime_path = ""
+        runtime_root = ""
+        runtime_type = ""
+        sandbox_mode = ""
+        snapshotter = ""
+
+        [plugins."io.containerd.grpc.v1.cri".containerd.default_runtime.options]
+
+      [plugins."io.containerd.grpc.v1.cri".containerd.runtimes]
+
+        [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
+          base_runtime_spec = ""
+          cni_conf_dir = ""
+          cni_max_conf_num = 0
+          container_annotations = []
+          pod_annotations = []
+          privileged_without_host_devices = false
+          privileged_without_host_devices_all_devices_allowed = false
+          runtime_engine = ""
+          runtime_path = ""
+          runtime_root = ""
+          runtime_type = "io.containerd.runc.v2"
+          sandbox_mode = "podsandbox"
+          snapshotter = ""
+
+          [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
+            BinaryName = ""
+            CriuImagePath = ""
+            CriuWorkPath = ""
+            IoGid = 0
+            IoUid = 0
+            NoNewKeyring = false
+            Root = ""
+            ShimCgroup = ""
+            # Removed in latest
+            #CriuPath = ""
+            #NoPivotRoot = false
+            #SystemdCgroup = false
+
+      [plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime]
+        base_runtime_spec = ""
+        cni_conf_dir = ""
+        cni_max_conf_num = 0
+        container_annotations = []
+        pod_annotations = []
+        privileged_without_host_devices = false
+        privileged_without_host_devices_all_devices_allowed = false
+        runtime_engine = ""
+        runtime_path = ""
+        runtime_root = ""
+        runtime_type = ""
+        sandbox_mode = ""
+        snapshotter = ""
+
+        [plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime.options]
+
+    [plugins."io.containerd.grpc.v1.cri".image_decryption]
+      key_model = "node"
+
+    [plugins."io.containerd.grpc.v1.cri".registry]
+      config_path = ""
+
+      [plugins."io.containerd.grpc.v1.cri".registry.auths]
+
+      [plugins."io.containerd.grpc.v1.cri".registry.configs]
+
+      [plugins."io.containerd.grpc.v1.cri".registry.headers]
+
+      [plugins."io.containerd.grpc.v1.cri".registry.mirrors]
+
+    [plugins."io.containerd.grpc.v1.cri".x509_key_pair_streaming]
+      tls_cert_file = ""
+      tls_key_file = ""
+
+  [plugins."io.containerd.internal.v1.opt"]
+    path = "/opt/containerd"
+
+  [plugins."io.containerd.internal.v1.restart"]
+    interval = "10s"
+
+  [plugins."io.containerd.internal.v1.tracing"]
+    sampling_ratio = 1.0
+    service_name = "containerd"
+
+  [plugins."io.containerd.metadata.v1.bolt"]
+    content_sharing_policy = "shared"
+
+  [plugins."io.containerd.monitor.v1.cgroups"]
+    no_prometheus = false
+
+  [plugins."io.containerd.nri.v1.nri"]
+    disable = true
+    disable_connections = false
+    plugin_config_path = "/etc/nri/conf.d"
+    plugin_path = "/opt/nri/plugins"
+    plugin_registration_timeout = "5s"
+    plugin_request_timeout = "2s"
+    socket_path = "/var/run/nri/nri.sock"
+
+  # Removed in latest
+  #[plugins."io.containerd.runtime.v1.linux"]
+  #  no_shim = false
+  #  runtime = "runc"
+  #  runtime_root = ""
+  #  shim = "containerd-shim"
+  #  shim_debug = false
+
+  [plugins."io.containerd.runtime.v2.task"]
+    platforms = ["linux/amd64"]
+    sched_core = false
+
+  [plugins."io.containerd.service.v1.diff-service"]
+    default = ["walking"]
+
+  [plugins."io.containerd.service.v1.tasks-service"]
+    blockio_config_file = ""
+    rdt_config_file = ""
+
+  # Removed in latest
+  #[plugins."io.containerd.snapshotter.v1.aufs"]
+  #  root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.blockfile"]
+    fs_type = ""
+    mount_options = []
+    root_path = ""
+    scratch_file = ""
+
+  [plugins."io.containerd.snapshotter.v1.btrfs"]
+    root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.devmapper"]
+    async_remove = false
+    base_image_size = ""
+    discard_blocks = false
+    fs_options = ""
+    fs_type = ""
+    pool_name = ""
+    root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.native"]
+    root_path = ""
+
+  [plugins."io.containerd.snapshotter.v1.overlayfs"]
+    mount_options = []
+    root_path = ""
+    sync_remove = false
+    upperdir_label = false
+
+  # Removed in latest
+  #[plugins."io.containerd.snapshotter.v1.zfs"]
+  #  root_path = ""
+
+  [plugins."io.containerd.tracing.processor.v1.otlp"]
+    endpoint = ""
+    insecure = false
+    protocol = ""
+
+  [plugins."io.containerd.transfer.v1.local"]
+    config_path = ""
+    max_concurrent_downloads = 3
+    max_concurrent_uploaded_layers = 3
+
+    # In 2.0, the default unpack config is applied when not specified
+    #[[plugins."io.containerd.transfer.v1.local".unpack_config]]
+    #  differ = ""
+    #  platform = "linux/amd64"
+    #  snapshotter = "overlayfs"
+
+[proxy_plugins]
+
+[stream_processors]
+
+  [stream_processors."io.containerd.ocicrypt.decoder.v1.tar"]
+    accepts = ["application/vnd.oci.image.layer.v1.tar+encrypted"]
+    args = ["--decryption-keys-path", "/etc/containerd/ocicrypt/keys"]
+    env = ["OCICRYPT_KEYPROVIDER_CONFIG=/etc/containerd/ocicrypt/ocicrypt_keyprovider.conf"]
+    path = "ctd-decoder"
+    returns = "application/vnd.oci.image.layer.v1.tar"
+
+  [stream_processors."io.containerd.ocicrypt.decoder.v1.tar.gzip"]
+    accepts = ["application/vnd.oci.image.layer.v1.tar+gzip+encrypted"]
+    args = ["--decryption-keys-path", "/etc/containerd/ocicrypt/keys"]
+    env = ["OCICRYPT_KEYPROVIDER_CONFIG=/etc/containerd/ocicrypt/ocicrypt_keyprovider.conf"]
+    path = "ctd-decoder"
+    returns = "application/vnd.oci.image.layer.v1.tar+gzip"
+
+[timeouts]
+  "io.containerd.timeout.bolt.open" = "0s"
+  "io.containerd.timeout.metrics.shimstats" = "2s"
+  "io.containerd.timeout.shim.cleanup" = "5s"
+  "io.containerd.timeout.shim.load" = "5s"
+  "io.containerd.timeout.shim.shutdown" = "3s"
+  "io.containerd.timeout.task.state" = "2s"
+
+[ttrpc]
+  address = ""
+  gid = 0
+  uid = 0

pkg/cri/server/base/cri_base.go

@@ -69,6 +69,7 @@ func init() {
 			conf := c.(map[string]interface{})
 			migrateConfig(conf)
 			plugins["io.containerd.internal.v1.cri"] = conf
+			delete(plugins, "io.containerd.grpc.v1.cri")
 			return nil
 		},
 		InitFn: initCRIBase,

plugins/transfer/plugin.go

@@ -77,6 +77,17 @@ func init() {
 			var lc local.TransferConfig
 			lc.MaxConcurrentDownloads = config.MaxConcurrentDownloads
 			lc.MaxConcurrentUploadedLayers = config.MaxConcurrentUploadedLayers
+
+			// If UnpackConfiguration is not defined, set the default.
+			// If UnpackConfiguration is defined and empty, ignore.
+			if config.UnpackConfiguration == nil {
+				config.UnpackConfiguration = []unpackConfiguration{
+					{
+						Platform:    platforms.Format(platforms.DefaultSpec()),
+						Snapshotter: defaults.DefaultSnapshotter,
+					},
+				}
+			}
 			for _, uc := range config.UnpackConfiguration {
 				p, err := platforms.Parse(uc.Platform)
 				if err != nil {
@@ -148,7 +159,7 @@ type transferConfig struct {
 	MaxConcurrentUploadedLayers int `toml:"max_concurrent_uploaded_layers"`
 
 	// UnpackConfiguration is used to read config from toml
-	UnpackConfiguration []unpackConfiguration `toml:"unpack_config"`
+	UnpackConfiguration []unpackConfiguration `toml:"unpack_config,omitempty"`
 
 	// RegistryConfigPath is a path to the root directory containing registry-specific configurations
 	RegistryConfigPath string `toml:"config_path"`
@@ -169,11 +180,5 @@ func defaultConfig() *transferConfig {
 	return &transferConfig{
 		MaxConcurrentDownloads:      3,
 		MaxConcurrentUploadedLayers: 3,
-		UnpackConfiguration: []unpackConfiguration{
-			{
-				Platform:    platforms.Format(platforms.DefaultSpec()),
-				Snapshotter: defaults.DefaultSnapshotter,
-			},
-		},
 	}
 }