We have a multi-site domain with several sites in a hub and spoke-design. From the hub site, we have established a one-way trust to another domain though a VPN tunnel.
Now, when someone from the external domain tries to authenticate, our domain controllers will return a referral to the other domain. However, the tunnel is only open for the domain controllers in the hub site.
Can we somehow put use a proxy in this situation? I've been reading up on AD LDS, which comes up in searches on the topic, but it is not apparent to me how/if it would work. It seems OpenLDAP also has some proxy functionality, but I'd rather not introduce it unless it is the only option. Any other options?