How do I configure Subversion to authenticate against multiple LDAP domains?

For some configurations, a Subversion server may need to be authenticated against multiple LDAP domains. This is possible by modifying the Apache configuration.

This is now possible due to the mod_authn_alias module for Apache. The external link for the module contains multiple usage scenarios. You will need to confirm that your Apache has been compiled with the module enabled. (This is the case for CollabNet Subversion binary packages since 1.5.4). If it is compiled as a module, make sure it is enabled via the LoadModule directive in your Apache configuration.

Example configuration usage for authentication against three LDAP servers :

<AuthnProviderAlias ldap ldap-US>
    AuthLDAPBindDN cn=ldapuser,o=company
    AuthLDAPBindPassword password
    AuthLDAPURL ldap://ldap-us.company.local/ou=Developers,o=company?sub?(objectClass=*)
</AuthnProviderAlias>

<AuthnProviderAlias ldap ldap-EU>
    AuthLDAPBindDN cn=ldapuser,o=company
    AuthLDAPBindPassword password
    AuthLDAPURL ldap://ldap-EU.company.local/ou=Developers,o=company?sub?(objectClass=*)
</AuthnProviderAlias>

<AuthnProviderAlias ldap ldap-IN>
    AuthLDAPBindDN cn=ldapuser,o=company
    AuthLDAPBindPassword password
    AuthLDAPURL ldap://ldap-in.company.local/ou=Developers,o=company?sub?(objectClass=*)
</AuthnProviderAlias>

<Location /svn>
    DAV svn
    SVNParentPath /opt/subversion/repos
    AuthType Basic
    AuthName "Subversion Repository"
    AuthBasicProvider ldap-US ldap-EU ldap-IN
    AuthzLDAPAuthoritative off
    Require valid-user
</Location>