5 files changed, 49 insertions, 31 deletions
diff --git a/doc/ci/docker/README.md b/doc/ci/docker/README.md
deleted file mode 100644
index 577a80407d7..00000000000
--- a/doc/ci/docker/README.md
+++ /dev/null
@@ -1,9 +0,0 @@
----
-redirect_to: 'index.md'
-remove_date: '2021-05-01'
----
-
-This document was moved to [another location](index.md).
-
-<!-- This redirect file can be deleted after 2021-05-01. -->
-<!-- Before deletion, see: https://docs.gitlab.com/ee/development/documentation/#move-or-rename-a-page -->
diff --git a/doc/ci/docker/index.md b/doc/ci/docker/index.md
index 20599c5ca85..4f6da72af12 100644
--- a/doc/ci/docker/index.md
+++ b/doc/ci/docker/index.md
@@ -6,9 +6,9 @@ comments: false
 type: index
 ---
 
-# Docker integration
+# Docker integration **(FREE)**
 
-There are two primary ways to incorporate [Docker](https://www.docker.com) in your CI/CD workflow.
+There are two primary ways to incorporate [Docker](https://www.docker.com) into your CI/CD workflow:
 
 - **[Run your CI/CD jobs](using_docker_images.md) in Docker containers.**
 
diff --git a/doc/ci/docker/using_docker_build.md b/doc/ci/docker/using_docker_build.md
index 9dac08324c8..c56bc9a4dc8 100644
--- a/doc/ci/docker/using_docker_build.md
+++ b/doc/ci/docker/using_docker_build.md
@@ -5,7 +5,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 type: concepts, howto
 ---
 
-# Use Docker to build Docker images
+# Use Docker to build Docker images **(FREE)**
 
 You can use GitLab CI/CD with Docker to create Docker images.
 For example, you can create a Docker image of your application,
@@ -25,8 +25,8 @@ To enable Docker commands for your CI/CD jobs, you can use:
 If you don't want to execute a runner in privileged mode,
 but want to use `docker build`, you can also [use kaniko](using_kaniko.md).
 
-If you are using shared runners on GitLab.com, 
-[learn more about how these runners are configured](../runners/README.md).
+If you are using shared runners on GitLab.com,
+[learn more about how these runners are configured](../runners/index.md).
 
 ### Use the shell executor
 
@@ -90,7 +90,7 @@ The Docker image has all of the `docker` tools installed and can run
 the job script in context of the image in privileged mode.
 
 We recommend you use [Docker-in-Docker with TLS enabled](#docker-in-docker-with-tls-enabled),
-which is supported by [GitLab.com shared runners](../runners/README.md).
+which is supported by [GitLab.com shared runners](../runners/index.md).
 
 You should always specify a specific version of the image, like `docker:19.03.12`.
 If you use a tag like `docker:stable`, you have no control over which version is used.
@@ -577,7 +577,7 @@ don't work because a fresh Docker daemon is started with the service.
 
 ### Option 1: Run `docker login`
 
-In [`before_script`](../yaml/README.md#before_script), run `docker
+In [`before_script`](../yaml/index.md#before_script), run `docker
 login`:
 
 ```yaml
@@ -682,10 +682,10 @@ There are multiple ways to define this authentication:
 
 - In [`pre_build_script`](https://docs.gitlab.com/runner/configuration/advanced-configuration.html#the-runners-section)
   in the runner configuration file.
-- In [`before_script`](../yaml/README.md#before_script).
-- In [`script`](../yaml/README.md#script).
+- In [`before_script`](../yaml/index.md#before_script).
+- In [`script`](../yaml/index.md#script).
 
-The following example shows [`before_script`](../yaml/README.md#before_script).
+The following example shows [`before_script`](../yaml/index.md#before_script).
 The same commands apply for any solution you implement.
 
 ```yaml
@@ -798,7 +798,7 @@ which can be avoided if a different driver is used, for example `overlay2`.
 ### Use the OverlayFS driver per project
 
 You can enable the driver for each project individually by using the `DOCKER_DRIVER`
-[CI/CD variable](../yaml/README.md#variables) in `.gitlab-ci.yml`:
+[CI/CD variable](../yaml/index.md#variables) in `.gitlab-ci.yml`:
 
 ```yaml
 variables:
@@ -840,3 +840,30 @@ This issue occurs because Docker starts on TLS automatically.
   [use the Docker executor with the Docker image](#use-the-docker-executor-with-the-docker-image-docker-in-docker).
 - If you are upgrading from v18.09 or earlier, read our
   [upgrade guide](https://about.gitlab.com/blog/2019/07/31/docker-in-docker-with-docker-19-dot-03/).
+
+### Docker `no such host` error
+
+You may get an error that says
+`docker: error during connect: Post https://docker:2376/v1.40/containers/create: dial tcp: lookup docker on x.x.x.x:53: no such host`.
+
+This issue can occur when the service's image name
+[includes a registry hostname](../../ci/services/index.md#available-settings-for-services). For example:
+
+```yaml
+image: docker:19.03.12
+
+services:
+  - registry.hub.docker.com/library/docker:19.03.12-dind
+```
+
+A service's hostname is [derived from the full image name](../../ci/services/index.md#accessing-the-services).
+However, the shorter service hostname `docker` is expected.
+To allow service resolution and access, add an explicit alias for the service name `docker`:
+
+```yaml
+image: docker:19.03.12
+
+services:
+  - name: registry.hub.docker.com/library/docker:19.03.12-dind
+    alias: docker
+```
diff --git a/doc/ci/docker/using_docker_images.md b/doc/ci/docker/using_docker_images.md
index 29f4053f720..c2991ce66f9 100644
--- a/doc/ci/docker/using_docker_images.md
+++ b/doc/ci/docker/using_docker_images.md
@@ -5,7 +5,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 type: concepts, howto
 ---
 
-# Run your CI/CD jobs in Docker containers
+# Run your CI/CD jobs in Docker containers **(FREE)**
 
 You can run your CI/CD jobs in separate, isolated Docker containers.
 
@@ -153,9 +153,9 @@ CI/CD jobs:
    from `Dockerfile` that may be overridden in the `.gitlab-ci.yml` file.
 1. The runner attaches itself to a running container.
 1. The runner prepares a script (the combination of
-   [`before_script`](../yaml/README.md#before_script),
-   [`script`](../yaml/README.md#script),
-   and [`after_script`](../yaml/README.md#after_script)).
+   [`before_script`](../yaml/index.md#before_script),
+   [`script`](../yaml/index.md#script),
+   and [`after_script`](../yaml/index.md#after_script)).
 1. The runner sends the script to the container's shell `stdin` and receives the
    output.
 
@@ -225,7 +225,7 @@ To access private container registries, the GitLab Runner process can use:
 To define which option should be used, the runner process reads the configuration in this order:
 
 - A `DOCKER_AUTH_CONFIG` variable provided as either:
-  - A [CI/CD variable](../variables/README.md) in the `.gitlab-ci.yml` file.
+  - A [CI/CD variable](../variables/index.md) in the `.gitlab-ci.yml` file.
   - A project's variables stored on the project's **Settings > CI/CD** page.
 - A `DOCKER_AUTH_CONFIG` variable provided as environment variable in the runner's `config.toml` file.
 - A `config.json` file in `$HOME/.docker` directory of the user running the process.
@@ -322,7 +322,7 @@ Use one of the following methods to determine the value of `DOCKER_AUTH_CONFIG`:
 To configure a single job with access for `registry.example.com:5000`,
 follow these steps:
 
-1. Create a [CI/CD variable](../variables/README.md) `DOCKER_AUTH_CONFIG` with the content of the
+1. Create a [CI/CD variable](../variables/index.md) `DOCKER_AUTH_CONFIG` with the content of the
    Docker configuration file as the value:
 
    ```json
@@ -395,7 +395,7 @@ To configure a Credentials Store:
 1. Make GitLab Runner use it. There are two ways to accomplish this. Either:
 
    - Create a
-     [CI/CD variable](../variables/README.md)
+     [CI/CD variable](../variables/index.md)
      `DOCKER_AUTH_CONFIG` with the content of the
      Docker configuration file as the value:
 
@@ -427,7 +427,7 @@ To configure access for `aws_account_id.dkr.ecr.region.amazonaws.com`, follow th
    Make sure that GitLab Runner can access the credentials.
 1. Make GitLab Runner use it. There are two ways to accomplish this. Either:
 
-   - Create a [CI/CD variable](../variables/README.md)
+   - Create a [CI/CD variable](../variables/index.md)
      `DOCKER_AUTH_CONFIG` with the content of the
      Docker configuration file as the value:
 
diff --git a/doc/ci/docker/using_kaniko.md b/doc/ci/docker/using_kaniko.md
index 05769cc8f75..108d4e0dcad 100644
--- a/doc/ci/docker/using_kaniko.md
+++ b/doc/ci/docker/using_kaniko.md
@@ -5,7 +5,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 type: howto
 ---
 
-# Use kaniko to build Docker images
+# Use kaniko to build Docker images **(FREE)**
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/45512) in GitLab 11.2. Requires GitLab Runner 11.2 and above.
 
@@ -49,7 +49,7 @@ In the following example, kaniko is used to:
 
 The job runs only when a tag is pushed. A `config.json` file is created under
 `/kaniko/.docker` with the needed GitLab Container Registry credentials taken from the
-[predefined CI/CD variables](../variables/README.md#predefined-cicd-variables)
+[predefined CI/CD variables](../variables/index.md#predefined-cicd-variables)
 GitLab CI/CD provides.
 
 In the last step, kaniko uses the `Dockerfile` under the
@@ -133,7 +133,7 @@ The [Least Privilege Container Builds with Kaniko on GitLab](https://www.youtube
 video is a walkthrough of the [Kaniko Docker Build](https://gitlab.com/guided-explorations/containers/kaniko-docker-build)
 Guided Exploration project pipeline. It was tested on:
 
-- [GitLab.com shared runners](../runners/README.md)
+- [GitLab.com shared runners](../runners/index.md)
 - [The Kubernetes runner executor](https://docs.gitlab.com/runner/executors/kubernetes.html)
 
 The example can be copied to your own group or instance for testing. More details