Added ldap config setting to lower case usernames

1 files changed, 39 insertions, 0 deletions

diff --git a/doc/administration/auth/ldap.md b/doc/administration/auth/ldap.md
index 881b6a827f4..63fbb24bac1 100644
--- a/doc/administration/auth/ldap.md
+++ b/doc/administration/auth/ldap.md
@@ -181,6 +181,10 @@ main: # 'main' is the GitLab 'provider ID' of this LDAP server
     first_name: 'givenName'
     last_name:  'sn'
 
+  # If lowercase_usernames is enabled, GitLab will lower case the username.
+  lowercase_usernames: false
+
+
   ## EE only
 
   # Base where we can search for groups
@@ -290,6 +294,41 @@ In other words, if an existing GitLab user wants to enable LDAP sign-in for
 themselves, they should check that their GitLab email address matches their
 LDAP email address, and then sign into GitLab via their LDAP credentials.
 
+## Enabling LDAP username lowercase
+
+Some LDAP servers, depending on their configurations, can return uppercase usernames. This can lead to several confusing issues like, for example, creating links or namespaces with uppercase names.
+
+GitLab can automatically lowercase usernames provided by the LDAP server by enabling
+the configuration option `lowercase_usernames`. By default, this configuration option is `false`.
+
+**Omnibus configuration**
+
+1. Edit `/etc/gitlab/gitlab.rb`:
+
+  ```ruby
+  gitlab_rails['ldap_servers'] = YAML.load <<-EOS
+  main:
+    # snip...
+    lowercase_usernames: true
+  EOS
+  ```
+
+2. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect.
+
+**Source configuration**
+
+1. Edit `config/gitlab.yaml`:
+
+  ```yaml
+  production:
+    ldap:
+      servers:
+        main:
+          # snip...
+          lowercase_usernames: true
+  ```
+2. [Restart GitLab](../restart_gitlab.md#installations-from-source) for the changes to take effect.
+
 ## Encryption
 
 ### TLS Server Authentication