Merge pull request #66587 from feiskyer/revert-63905

Automatic merge from submit-queue (batch tested with PRs 66491, 66587, 66856, 66657, 66923). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Revert #63905: Setup dns servers and search domains for Windows Pods

**What this PR does / why we need it**:

From https://github.com/kubernetes/kubernetes/pull/63905#issuecomment-396709775:

> I don't think this change does anything on Windows. On windows, the network endpoint configuration is taken care of completely by CNI. If you would like to pass on the custom dns polices from the pod spec, it should be dynamically going to the cni configuration that gets passed to CNI. From there, it would be passed down to platform and would be taken care of appropriately by HNS.

> etc\resolve.conf is very specific to linux and that should remain linux speicfic implementation. We should be trying to move away from platform specific code in Kubelet.
Docker is not managing the networking here for windows. So it doens't really care about any network settings. So passing it to docker shim's hostconfig also doens;t make sense here.

DNS for Windows containers will be set by CNI plugins.  And this change also introduced two endpoints for sandbox container.  So this PR reverts #63905 .


**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #

**Special notes for your reviewer**:

The PR should also be cherry-picked to release-1.11.

Also, https://github.com/kubernetes/kubernetes/issues/66588 is opened to track the process of pushing this to CNI.

**Release note**:

```release-note
Revert #63905: Setup dns servers and search domains for Windows Pods. DNS for Windows containers will be set by CNI plugins.
```

/sig windows
/sig node
/kind bug

pkg/kubelet/dockershim/BUILD

@@ -14,8 +14,6 @@ go_library(
         "docker_legacy_service.go",
         "docker_logs.go",
         "docker_sandbox.go",
-        "docker_sandbox_others.go",
-        "docker_sandbox_windows.go",
         "docker_service.go",
         "docker_stats_linux.go",
         "docker_stats_unsupported.go",

pkg/kubelet/dockershim/docker_sandbox.go

@@ -538,6 +538,21 @@ func (ds *dockerService) ListPodSandbox(_ context.Context, r *runtimeapi.ListPod
 	return &runtimeapi.ListPodSandboxResponse{Items: result}, nil
 }
 
+// applySandboxLinuxOptions applies LinuxPodSandboxConfig to dockercontainer.HostConfig and dockercontainer.ContainerCreateConfig.
+func (ds *dockerService) applySandboxLinuxOptions(hc *dockercontainer.HostConfig, lc *runtimeapi.LinuxPodSandboxConfig, createConfig *dockertypes.ContainerCreateConfig, image string, separator rune) error {
+	if lc == nil {
+		return nil
+	}
+	// Apply security context.
+	if err := applySandboxSecurityContext(lc, createConfig.Config, hc, ds.network, separator); err != nil {
+		return err
+	}
+
+	// Set sysctls.
+	hc.Sysctls = lc.Sysctls
+	return nil
+}
+
 func (ds *dockerService) applySandboxResources(hc *dockercontainer.HostConfig, lc *runtimeapi.LinuxPodSandboxConfig) error {
 	hc.Resources = dockercontainer.Resources{
 		MemorySwap: DefaultMemorySwap(),
@@ -578,8 +593,8 @@ func (ds *dockerService) makeSandboxDockerConfig(c *runtimeapi.PodSandboxConfig,
 		HostConfig: hc,
 	}
 
-	// Apply platform-specific options.
-	if err := ds.applySandboxPlatformOptions(hc, c, createConfig, image, securityOptSeparator); err != nil {
+	// Apply linux-specific options.
+	if err := ds.applySandboxLinuxOptions(hc, c.GetLinux(), createConfig, image, securityOptSeparator); err != nil {
 		return nil, err
 	}
 

pkg/kubelet/dockershim/docker_sandbox_others.go

@@ -1,42 +0,0 @@
-// +build !windows
-
-/*
-Copyright 2018 The Kubernetes 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 dockershim
-
-import (
-	dockertypes "github.com/docker/docker/api/types"
-	dockercontainer "github.com/docker/docker/api/types/container"
-	runtimeapi "k8s.io/kubernetes/pkg/kubelet/apis/cri/runtime/v1alpha2"
-)
-
-// applySandboxPlatformOptions applies platform specific options to dockercontainer.HostConfig and dockercontainer.ContainerCreateConfig.
-func (ds *dockerService) applySandboxPlatformOptions(hc *dockercontainer.HostConfig, config *runtimeapi.PodSandboxConfig, createConfig *dockertypes.ContainerCreateConfig, image string, separator rune) error {
-	lc := config.GetLinux()
-	if lc == nil {
-		return nil
-	}
-
-	// Apply security context.
-	if err := applySandboxSecurityContext(lc, createConfig.Config, hc, ds.network, separator); err != nil {
-		return err
-	}
-
-	// Set sysctls.
-	hc.Sysctls = lc.Sysctls
-	return nil
-}

pkg/kubelet/dockershim/docker_sandbox_windows.go

@@ -1,39 +0,0 @@
-// +build windows
-
-/*
-Copyright 2018 The Kubernetes 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 dockershim
-
-import (
-	dockertypes "github.com/docker/docker/api/types"
-	dockercontainer "github.com/docker/docker/api/types/container"
-	runtimeapi "k8s.io/kubernetes/pkg/kubelet/apis/cri/runtime/v1alpha2"
-)
-
-// applySandboxPlatformOptions applies platform specific options to dockercontainer.HostConfig and dockercontainer.ContainerCreateConfig.
-func (ds *dockerService) applySandboxPlatformOptions(hc *dockercontainer.HostConfig, config *runtimeapi.PodSandboxConfig, createConfig *dockertypes.ContainerCreateConfig, image string, separator rune) error {
-	dnsConfig := config.GetDnsConfig()
-	if dnsConfig == nil {
-		return nil
-	}
-
-	// Setup DNS.
-	hc.DNS = dnsConfig.GetServers()
-	hc.DNSSearch = dnsConfig.GetSearches()
-	hc.DNSOptions = dnsConfig.GetOptions()
-	return nil
-}