Describe the feature you'd like

Apologies if this is already something that can be configured but I haven't seen a guide on how if so.

It would be great if the Bookstack .env gave the option to configure an alternative LDAP address that could be used if a lookup fails. We recently lost access to a DC (thanks Microsoft for January patching fun) and our other DCs could have kept the service alive if Bookstack knew where to look after the first failed lookup.

Describe the benefits this feature would bring to BookStack users

LDAP logins would continue to function if a single DC was offline or malfunctioning. Greatly increasing availability of the Bookstack service.

Additional context

No response