Apache + LDAP

OpenLDAP Should be installed priorly.

In Apache.conf file add the following lines :
LoadModule ldap_module <Path to mod_ldap.so>/mod_ldap.so
LoadModule authnz_ldap_module <Path to mod_authnz_ldap.so>/mod_authnz_ldap.so
<LocationMatch "/login">
    AuthType Basic
    AuthName "Testing"
    AuthBasicProvider "ldap"
    AuthLDAPURL "ldap://host:port/dc=example,dc=org?cn" #
    AuthLDAPBindDN "cn=Manager,dc=example,,dc=org" #
    AuthLDAPBindPassword "123" #
    AuthzLDAPAuthoritative off
    require valid-user
</LocationMatch>

Note: in # marked lines, put your server values.

Restart Apache.
root@otc-desktop:~# /etc/init.d/apache2 reload