Add latest changes from gitlab-org/gitlab@master

doc/administration/index.md

@@ -51,7 +51,7 @@ Learn how to install, configure, update, and maintain your GitLab instance.
 - [Polling](polling.md): Configure how often the GitLab UI polls for updates.
 - [GitLab Pages configuration](pages/index.md): Enable and configure GitLab Pages.
 - [GitLab Pages configuration for GitLab source installations](pages/source.md): Enable and configure GitLab Pages on [source installations](../install/installation.md#installation-from-source).
-- [Uploads configuration](uploads.md): Configure GitLab uploads storage.
+- [Uploads administration](uploads.md): Configure GitLab uploads storage.
 - [Environment variables](environment_variables.md): Supported environment variables that can be used to override their defaults values in order to configure GitLab.
 - [Plugins](plugins.md): With custom plugins, GitLab administrators can introduce custom integrations without modifying GitLab's source code.
 - [Enforcing Terms of Service](../user/admin_area/settings/terms.md)

doc/ci/docker/using_docker_build.md

@@ -728,14 +728,18 @@ is set to `always`.
 [2fa]: ../../user/profile/account/two_factor_authentication.md
 [pat]: ../../user/profile/personal_access_tokens.md
 
-<!-- ## Troubleshooting
+## Troubleshooting
 
-Include any troubleshooting steps that you can foresee. If you know beforehand what issues
-one might have when setting this up, or when something is changed, or on upgrading, it's
-important to describe those, too. Think of things that may go wrong and include them here.
-This is important to minimize requests for support, and to avoid doc comments with
-questions that you know someone might ask.
+### docker: Cannot connect to the Docker daemon at tcp://docker:2375. Is the docker daemon running?
 
-Each scenario can be a third-level heading, e.g. `### Getting error message X`.
-If you have none to add when creating a doc, leave this section in place
-but commented out to help encourage others to add to it in the future. -->
+This is a common error when you are using
+[Docker in Docker](#use-docker-in-docker-workflow-with-docker-executor)
+v19.03 or higher.
+
+This occurs because Docker starts on TLS automatically, so you need to do some set up.
+If:
+
+- This is the first time setting it up, carefully read
+  [using Docker in Docker workflow](#use-docker-in-docker-workflow-with-docker-executor).
+- 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/).

doc/ci/variables/README.md

@@ -54,25 +54,37 @@ or directly in the `.gitlab-ci.yml` file and reuse them as you wish.
 That can be very powerful as it can be used for scripting without
 the need to specify the value itself.
 
-#### Variable types
+#### Types of variables
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/issues/46806) in GitLab 11.11.
 
 There are two types of variables supported by GitLab:
 
-- "Variable": the Runner will create an environment variable named same as the variable key and set its value to the variable value.
-- "File": the Runner will write the variable value to a temporary file and set the path to this file as the value of an environment variable named same as the variable key.
+- [Variable type](#variable-type): The Runner will create an environment variable named the same as the
+  variable key and set its value to the variable value.
+- [File type](#file-type): The Runner will write the variable value to a temporary file and set the
+  path to this file as the value of an environment variable, named the same as the variable key.
 
-Many tools (like [AWS CLI](https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-envvars.html) and [kubectl](https://kubernetes.io/docs/concepts/configuration/organize-cluster-access-kubeconfig/#the-kubeconfig-environment-variable)) provide the ability to customise configuration using files by either providing the file path as a command line argument or an environment variable. Prior to the introduction of variable types, the common pattern was to use the value of a CI variable, save it in a file, and then use the newly created file in your script:
+##### Variable type
+
+Many tools (like [AWS CLI](https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-envvars.html)
+and [kubectl](https://kubernetes.io/docs/concepts/configuration/organize-cluster-access-kubeconfig/#the-kubeconfig-environment-variable))
+provide the ability to customise configuration using files by either providing the
+file path as a command line argument or an environment variable. In the past, the
+common pattern was to read the value of a CI variable, save it in a file, and then
+use the newly created file in your script:
 
 ```bash
-# Save the content of variable in a file
+# Read certificate stored in $KUBE_CA_PEM variable and save it in a new file
 echo "$KUBE_CA_PEM" > "$(pwd)/kube.ca.pem"
- # Use the newly created file
+# Pass the newly created file to kubectl
 kubectl config set-cluster e2e --server="$KUBE_URL" --certificate-authority="$(pwd)/kube.ca.pem"
 ```
 
-This can be simplified by creating a variable of type "File" and using it directly. For example, let's say we have the following variables.
+##### File type
+
+The example above can now be simplified by creating a "File" type variable, and using
+it directly. For example, let's say we have the following variables:
 
 ![CI/CD settings - variable types usage example](img/variable_types_usage_example.png)