Gitlab Authentication with LDAP

Install self-managed GitLab

GitLab Server Details

Attribute Value
IP Address 192.168.1.10
FQDN gitlab.local.com

LDAP Server Details

Attribute Value
IP Address 192.168.1.9
FQDN ad.local.com
LDAP Base DN dc=local,dc=com
LDAP Bind DN cn=bind_user,dc=local,dc=com
Bind User Password your_bind_user_password

GitLab LDAP Configuration Steps

Step Description
1 Open GitLab Configuration File:
SSH into your GitLab server:
ssh root@gitlab.local.com
Open the GitLab configuration file:
sudo nano /etc/gitlab/gitlab.rb
2 Configure LDAP Settings:
Add the following LDAP configuration to /etc/gitlab/gitlab.rb		 
gitlab_rails['ldap_enabled'] = true
gitlab_rails['ldap_servers'] = YAML.load <<-EOS
main:
   label: 'LDAP'
   host: '192.168.1.9'
   port: 389
   uid: 'sAMAccountName'
   bind_dn: 'cn=bind_user,dc=local,dc=com'  # Replace with your actual bind DN
   password: 'your_bind_user_password'      # Replace with actual passwords' if needed
   verify_certificates: true
   active_directory: true
   allow_username_or_email_login: true
   user_filter: ''
   group_base: ''
   sync_ssh_keys: false
EOS

  1. Reconfigure GitLab:
    Run the following command to reconfigure GitLab:
    sudo gitlab-ctl reconfigure

  2. Verify LDAP Configuration:
    Log into GitLab with an LDAP user account to ensure the configuration works.

  3. Test Connection (Optional):
    Test the LDAP connection using ldapsearch:
    ldapsearch -x -H ldap://192.168.1.9 -D "cn=bind_user,dc=local,dc=com" -w "your_bind_user_password" -b "dc=local,dc=com"

Conclusion

You have successfully configured GitLab to authenticate users against your LDAP server. Users should now be able to log in using their LDAP credentials.