Fix yet more external link redirects

Updating links to external sites based on HTTP response codes.

doc/development/elasticsearch.md

@@ -15,7 +15,7 @@ the [Elasticsearch integration documentation](../integration/elasticsearch.md#en
 
 In June 2019, Mario de la Ossa hosted a Deep Dive (GitLab team members only: `https://gitlab.com/gitlab-org/create-stage/issues/1`) on GitLab's [Elasticsearch integration](../integration/elasticsearch.md) to share his domain specific knowledge with anyone who may work in this part of the code base in the future. You can find the [recording on YouTube](https://www.youtube.com/watch?v=vrvl-tN2EaA), and the slides on [Google Slides](https://docs.google.com/presentation/d/1H-pCzI_LNrgrL5pJAIQgvLX8Ji0-jIKOg1QeJQzChug/edit) and in [PDF](https://gitlab.com/gitlab-org/create-stage/uploads/c5aa32b6b07476fa8b597004899ec538/Elasticsearch_Deep_Dive.pdf). Everything covered in this deep dive was accurate as of GitLab 12.0, and while specific details may have changed since then, it should still serve as a good introduction.
 
-In August 2020, a second Deep Dive was hosted, focusing on [GitLab's specific architecture for multi-indices support](#zero-downtime-reindexing-with-multiple-indices). The [recording on YouTube](https://www.youtube.com/watch?v=0WdPR9oB2fg) and the [slides](https://lulalala.gitlab.io/gitlab-elasticsearch-deepdive) are available. Everything covered in this deep dive was accurate as of GitLab 13.3.
+In August 2020, a second Deep Dive was hosted, focusing on [GitLab's specific architecture for multi-indices support](#zero-downtime-reindexing-with-multiple-indices). The [recording on YouTube](https://www.youtube.com/watch?v=0WdPR9oB2fg) and the [slides](https://lulalala.gitlab.io/gitlab-elasticsearch-deepdive/) are available. Everything covered in this deep dive was accurate as of GitLab 13.3.
 
 ## Supported Versions
 

doc/user/project/import/clearcase.md

@@ -7,7 +7,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 
 # Migrating from ClearCase
 
-[ClearCase](https://www.ibm.com/us-en/marketplace/rational-clearcase) is a set of
+[ClearCase](https://www.ibm.com/products/rational-clearcase) is a set of
 tools developed by IBM which also include a centralized version control system
 similar to Git.
 

doc/user/project/import/github.md

@@ -60,7 +60,7 @@ must meet one of the following conditions prior to the import:
 
 - Have previously logged in to a GitLab account using the GitHub icon.
 - Have a GitHub account with a
-  [primary email address](https://docs.github.com/en/github/setting-up-and-managing-your-github-user-account/setting-your-commit-email-address)
+  [primary email address](https://docs.github.com/en/free-pro-team@latest/github/setting-up-and-managing-your-github-user-account/setting-your-commit-email-address)
   that matches their GitLab account's email address.
 
 If a user referenced in the project is not found in GitLab's database, the project creator (typically the user
@@ -89,7 +89,7 @@ Before you begin, ensure that any GitHub users who you want to map to GitLab use
 
 - A GitLab account that has logged in using the GitHub icon
   \- or -
-- A GitLab account with an email address that matches the [public email address](https://docs.github.com/en/github/setting-up-and-managing-your-github-user-account/setting-your-commit-email-address) of the GitHub user
+- A GitLab account with an email address that matches the [public email address](https://docs.github.com/en/free-pro-team@latest/github/setting-up-and-managing-your-github-user-account/setting-your-commit-email-address) of the GitHub user
 
 User-matching attempts occur in that order, and if a user is not identified either way, the activity is associated with
 the user account that is performing the import.

doc/user/project/integrations/github.md

@@ -20,7 +20,7 @@ and is automatically configured on [GitHub import](../../../integration/github.m
 
 ### Complete these steps on GitHub
 
-This integration requires a [GitHub API token](https://docs.github.com/en/github/authenticating-to-github/creating-a-personal-access-token)
+This integration requires a [GitHub API token](https://docs.github.com/en/free-pro-team@latest/github/authenticating-to-github/creating-a-personal-access-token)
 with `repo:status` access granted:
 
 1. Go to your "Personal access tokens" page at <https://github.com/settings/tokens>

doc/user/project/integrations/jira_integrations.md

@@ -19,7 +19,7 @@ The following Jira integrations allow different types of cross-referencing betwe
 
 - [**Jira integration**](jira.md) - This is built in to GitLab. In a given GitLab project, it can be configured to connect to any Jira instance, self-managed or Cloud.
 - [**Jira development panel integration**](../../../integration/jira_development_panel.md) - This connects all GitLab projects under a specified group or personal namespace.
-  - If you're using Jira Cloud and GitLab.com, install the [GitLab for Jira](https://marketplace.atlassian.com/apps/1221011/gitlab-for-jira) app in the Atlassian Marketplace and see its [documentation](../../../integration/jira_development_panel.md#gitlab-for-jira-app).
+  - If you're using Jira Cloud and GitLab.com, install the [GitLab for Jira](https://marketplace.atlassian.com/apps/1221011/gitlab-com-for-jira-cloud) app in the Atlassian Marketplace and see its [documentation](../../../integration/jira_development_panel.md#gitlab-for-jira-app).
   - For all other environments, use the [Jira DVCS Connector configuration instructions](../../../integration/jira_development_panel.md#configuration).
 
 ### Feature comparison

doc/user/project/integrations/webex_teams.md

@@ -10,7 +10,7 @@ You can configure GitLab to send notifications to a Webex Teams space.
 
 ## Create a webhook for the space
 
-1. Go to the [Incoming Webhooks app page](https://apphub.webex.com/teams/applications/incoming-webhooks-cisco-systems-38054).
+1. Go to the [Incoming Webhooks app page](https://apphub.webex.com/messaging/applications/incoming-webhooks-cisco-systems-38054).
 1. Click **Connect** and log in to Webex Teams, if required.
 1. Enter a name for the webhook and select the space to receive the notifications.
 1. Click **ADD**.

doc/user/project/pages/custom_domains_ssl_tls_certification/index.md

@@ -167,7 +167,7 @@ from the GitLab project.
 > - Domain verification is **required for GitLab.com users**;
   for GitLab self-managed instances, your GitLab administrator has the option
   to [disabled custom domain verification](../../../../administration/pages/index.md#custom-domain-verification).
-> - [DNS propagation may take some time (up to 24h)](https://www.inmotionhosting.com/support/domain-names/dns-nameserver-changes/domain-names-dns-changes/),
+> - [DNS propagation may take some time (up to 24h)](https://www.inmotionhosting.com/support/domain-names/dns-nameserver-changes/complete-guide-to-dns-records/),
   although it's usually a matter of minutes to complete. Until it does, verification
   will fail and attempts to visit your domain will respond with a 404.
 > - Once your domain has been verified, leave the verification record

doc/user/project/pages/custom_domains_ssl_tls_certification/ssl_tls_concepts.md

@@ -56,7 +56,7 @@ reiterating the importance of HTTPS.
 
 ## Issuing Certificates
 
-GitLab Pages accepts certificates provided in the [PEM](https://knowledge.digicert.com/quovadis) format, issued by
+GitLab Pages accepts certificates provided in the [PEM](https://knowledge.digicert.com/quovadis.html) format, issued by
 [Certificate Authorities](https://en.wikipedia.org/wiki/Certificate_authority) or as
 [self-signed certificates](https://en.wikipedia.org/wiki/Self-signed_certificate). Note that [self-signed certificates are typically not used](https://www.mcafee.com/blogs/other-blogs/mcafee-labs/self-signed-certificates-secure-so-why-ban/)
 for public websites for security reasons and to ensure that browsers trust your site's certificate.

doc/user/project/repository/repository_mirroring.md

@@ -124,7 +124,7 @@ After the mirror is created, this option can currently only be modified via the
 
 To set up a mirror from GitLab to GitHub, you need to follow these steps:
 
-1. Create a [GitHub personal access token](https://docs.github.com/en/github/authenticating-to-github/creating-a-personal-access-token) with the `public_repo` box checked.
+1. Create a [GitHub personal access token](https://docs.github.com/en/free-pro-team@latest/github/authenticating-to-github/creating-a-personal-access-token) with the `public_repo` box checked.
 1. Fill in the **Git repository URL** field using this format: `https://<your_github_username>@github.com/<your_github_group>/<your_github_project>.git`.
 1. Fill in **Password** field with your GitHub personal access token.
 1. Click the **Mirror repository** button.
@@ -320,7 +320,7 @@ fingerprints in the open for you to check:
 
 - [AWS CodeCommit](https://docs.aws.amazon.com/codecommit/latest/userguide/regions.html#regions-fingerprints)
 - [Bitbucket](https://support.atlassian.com/bitbucket-cloud/docs/configure-ssh-and-two-step-verification/)
-- [GitHub](https://docs.github.com/en/github/authenticating-to-github/githubs-ssh-key-fingerprints)
+- [GitHub](https://docs.github.com/en/free-pro-team@latest/github/authenticating-to-github/githubs-ssh-key-fingerprints)
 - [GitLab.com](../../gitlab_com/index.md#ssh-host-keys-fingerprints)
 - [Launchpad](https://help.launchpad.net/SSHFingerprints)
 - [Savannah](http://savannah.gnu.org/maintenance/SshAccess/)