Fixed some of the broken external links in GitLab documentation

doc/administration/auth/ldap/index.md

@@ -460,16 +460,12 @@ The LDAP sync process:
 
 ### Adjusting LDAP user sync schedule **(STARTER ONLY)**
 
-NOTE: **Note:**
-These are cron formatted values. You can use a crontab generator to create
-these values, for example <http://www.crontabgenerator.com/>.
-
 By default, GitLab runs a worker once per day at 01:30 a.m. server time to
 check and update GitLab users against LDAP.
 
 You can manually configure LDAP user sync times by setting the
 following configuration values, in cron format. If needed, you can
-use a [crontab generator](http://crontabgenerator.com).
+use a [crontab generator](http://www.crontabgenerator.com).
 The example below shows how to set LDAP user
 sync to run once every 12 hours at the top of the hour.
 

doc/administration/consul.md

@@ -87,7 +87,7 @@ Consul nodes communicate using the raft protocol. If the current leader goes
 offline, there needs to be a leader election. A leader node must exist to facilitate
 synchronization across the cluster. If too many nodes go offline at the same time,
 the cluster will lose quorum and not elect a leader due to
-[broken consensus](https://www.consul.io/docs/internals/consensus.html).
+[broken consensus](https://www.consul.io/docs/architecture/consensus).
 
 Consult the [troubleshooting section](#troubleshooting-consul) if the cluster is not
 able to recover after the upgrade. The [outage recovery](#outage-recovery) may

doc/administration/nfs.md

@@ -323,7 +323,7 @@ Any `Operation not permitted` errors means you should investigate your NFS serve
 If the traffic between your NFS server and NFS client(s) is subject to port filtering
 by a firewall, then you will need to reconfigure that firewall to allow NFS communication.
 
-[This guide from TDLP](http://tldp.org/HOWTO/NFS-HOWTO/security.html#FIREWALLS)
+[This guide from TDLP](https://tldp.org/HOWTO/NFS-HOWTO/security.html#FIREWALLS)
 covers the basics of using NFS in a firewalled environment. Additionally, we encourage you to
 search for and review the specific documentation for your operating system or distribution and your firewall software.
 

doc/ci/ci_cd_for_external_repos/github_integration.md

@@ -22,7 +22,7 @@ cannot be used to authenticate with GitHub as an external CI/CD repository.
 ## Connect with Personal Access Token
 
 Personal access tokens can only be used to connect GitHub.com
-repositories to GitLab, and the GitHub user must have the [owner role](https://docs.github.com/en/github/getting-started-with-github/access-permissions-on-github).
+repositories to GitLab, and the GitHub user must have the [owner role](https://docs.github.com/en/free-pro-team@latest/github/getting-started-with-github/access-permissions-on-github).
 
 To perform a one-off authorization with GitHub to grant GitLab access your
 repositories:

doc/ci/docker/using_docker_build.md

@@ -90,7 +90,7 @@ GitLab Runner then executes job scripts as the `gitlab-runner` user.
 1. You can now use `docker` command (and **install** `docker-compose` if needed).
 
 By adding `gitlab-runner` to the `docker` group you are effectively granting `gitlab-runner` full root permissions.
-For more information please read [On Docker security: `docker` group considered harmful](https://www.andreas-jung.com/contents/on-docker-security-docker-group-considered-harmful).
+For more information please read [On Docker security: `docker` group considered harmful](https://blog.zopyx.com/on-docker-security-docker-group-considered-harmful/).
 
 ### Use Docker-in-Docker workflow with Docker executor
 

doc/ci/examples/test_phoenix_app_with_gitlab_ci_cd/index.md

@@ -298,7 +298,7 @@ project.
     - mix ecto.migrate
    ```
 
-  This ensures that [rebar3](https://www.rebar3.org) and [hex](https://hex.pm) are both installed
+  This ensures that [rebar3](https://rebar3.org) and [hex](https://hex.pm) are both installed
   before attempting to fetch the dependencies that are required to run the tests. Next, the `postgres` db
   is created and migrated with `ecto`, to ensure it's up-to-date.
 

doc/ci/migration/circleci.md

@@ -10,7 +10,7 @@ type: index, howto
 
 If you are currently using CircleCI, you can migrate your CI/CD pipelines to [GitLab CI/CD](../introduction/index.md),
 and start making use of all its powerful features. Check out our
-[CircleCI vs GitLab](https://about.gitlab.com/devops-tools/circle-ci-vs-gitlab.html)
+[CircleCI vs GitLab](https://about.gitlab.com/devops-tools/circle-ci-vs-gitlab/)
 comparison to see what's different.
 
 We have collected several resources that you may find useful before starting to migrate.

doc/development/adding_service_component.md

@@ -4,7 +4,7 @@ The GitLab product is made up of several service components that run as independ
 
 ## Integration phases
 
-The following outline re-uses the [maturity metric](https://about.gitlab.com/direction/maturity) naming as an example of the various phases of integrating a component. These are only loosely coupled to a components actual maturity, and are intended as a guide for implementation order (for example, a component does not need to be enabled by default to be Lovable, and being enabled by default does not on its own cause a component to be Lovable).
+The following outline re-uses the [maturity metric](https://about.gitlab.com/direction/maturity/) naming as an example of the various phases of integrating a component. These are only loosely coupled to a components actual maturity, and are intended as a guide for implementation order (for example, a component does not need to be enabled by default to be Lovable, and being enabled by default does not on its own cause a component to be Lovable).
 
 - Proposed
   - [Proposing a new component](#proposing-a-new-component)

doc/development/documentation/styleguide.md

@@ -12,7 +12,7 @@ files.
 
 For broader information about the documentation, see the [Documentation guidelines](index.md).
 
-For guidelines specific to text in the GitLab interface, see the Pajamas [Content](https://design.gitlab.com/content/error-messages) section.
+For guidelines specific to text in the GitLab interface, see the Pajamas [Content](https://design.gitlab.com/content/error-messages/) section.
 
 For information on how to validate styles locally or by using GitLab CI/CD, see [Testing](index.md#testing).
 
@@ -25,7 +25,7 @@ If you can't find what you need:
 - View the GitLab Handbook for [writing style guidelines](https://about.gitlab.com/handbook/communication/#writing-style-guidelines) that apply to all GitLab content.
 - Refer to one of the following:
 
-  - [Microsoft Style Guide](https://docs.microsoft.com/en-us/style-guide/).
+  - [Microsoft Style Guide](https://docs.microsoft.com/en-us/style-guide/welcome/).
   - [Google Developer Documentation Style Guide](https://developers.google.com/style).
 
 If you have questions about style, mention `@tw-style` in an issue or merge request, or, if you have access to the GitLab Slack workspace, use `#docs-process`.
@@ -740,7 +740,7 @@ This is a list of available features:
 
 - Don't add commas (`,`) or semicolons (`;`) to the ends of list items.
 - Only add periods to the end of a list item if the item consists of a complete
-  sentence. The [definition of full sentence](https://www2.le.ac.uk/offices/ld/all-resources/writing/grammar/grammar-guides/sentence)
+  sentence. The [definition of full sentence](https://www.le.ac.uk/oerresources/ssds/grammarguides/page_02.htm)
   is: _"a complete sentence always contains a verb, expresses a complete idea, and makes sense standing alone"_.
 - Be consistent throughout the list: if the majority of the items do not end in
   a period, do not end any of the items in a period, even if they consist of a
@@ -1693,7 +1693,7 @@ own line and surrounded by blank lines.
   - `> [Introduced](<link-to-issue>) in GitLab 11.3.`.
 
 - If the feature is only available in GitLab Enterprise Edition, mention
-  the [paid tier](https://about.gitlab.com/handbook/marketing/product-marketing/#tiers)
+  the [paid tier](https://about.gitlab.com/handbook/marketing/strategic-marketing/tiers/)
   the feature is available in:
   - `> [Introduced](<link-to-issue>) in [GitLab Starter](https://about.gitlab.com/pricing/) 11.3.`.