Fix links to deprecated doc page

app/views/admin/application_settings/_form.html.haml

@@ -827,7 +827,7 @@
             to authenticate SSH keys via the database file. Only uncheck this
             if you have configured your OpenSSH server to use the
             AuthorizedKeysCommand. Click on the help icon for more details.
-            = link_to icon('question-circle'), help_page_path('administration/operations/speed_up_ssh', anchor: 'the-solution')
+            = link_to icon('question-circle'), help_page_path('administration/operations/fast_ssh_key_lookup')
   - if Gitlab.com? || Rails.env.development?
     %fieldset
       %legend Slack application

changelogs/unreleased-ee/mk-fix-fast-ssh-key-lookup-links.yml

+---
+title: Fix a few doc links to fast ssh key lookup
+merge_request: 3937
+author:
+type: fixed

db/migrate/20170626202753_update_authorized_keys_file.rb

@@ -80,7 +80,7 @@ class UpdateAuthorizedKeysFile < ActiveRecord::Migration
       option in Application Settings as outlined in the Speed up SSH
       documentation,
 
-      https://docs.gitlab.com/ee/administration/operations/speed_up_ssh.html
+      https://docs.gitlab.com/ee/administration/operations/fast_ssh_key_lookup.html
 
       then the authorized_keys file may be out-of-date, affecting SSH
       operations.

ee/lib/system_check/geo/authorized_keys_check.rb

@@ -3,7 +3,7 @@ module SystemCheck
     class AuthorizedKeysCheck < ::SystemCheck::BaseCheck
       set_name 'OpenSSH configured to use AuthorizedKeysCommand'
 
-      AUTHORIZED_KEYS_DOCS = 'doc/administration/operations/speed_up_ssh.md'.freeze
+      AUTHORIZED_KEYS_DOCS = 'doc/administration/operations/fast_ssh_key_lookup.md'.freeze
       OPENSSH_AUTHORIZED_KEYS_CMD_REGEXP = %r{
         ^AuthorizedKeysCommand # line starts with
         \s+                    # one space or more

lib/tasks/gitlab/shell.rake

@@ -161,7 +161,7 @@ namespace :gitlab do
       It should be enabled for most GitLab installations. Large installations
       may wish to disable it as part of speeding up SSH operations.
 
-      See https://docs.gitlab.com/ee/administration/operations/speed_up_ssh.html
+      See https://docs.gitlab.com/ee/administration/operations/fast_ssh_key_lookup.html
 
       If you did not intentionally disable this option in Admin Area > Settings,
       then you may have been affected by the 9.3.0 bug in which the new setting