thanks for the reply Alessandro
The issue I have is the 2 domains are isolated from each other, there is no trust or any connectivity.
The user will have logged into Domain A on their workstation or Terminal Server. If I used AD query against Domain A & Domain B, it would pick up the user from Domain A, but it wouldn't see any login events on Domain B for that user
The business requirement is that the user is authenticated against Domain B by the Check Point somehow. The only way I can see this working is to use Captive Portal where you could you just put the Domain B credentials into the webpage.
With a terminal server the only option seems to be to use the Identity Agent which would pass the user's Domain A credentials through.
I can't see any scenario where I can get terminal server user's to authenticate as Domain B users. Or is it possible to map the username from Domain A onto Domain B, so that the user log onto Domain A, the agent passes this to Check Point, and Check Point looks up the same username in Domain B, and we can allow access based on group membership or the fact that this account is active in Domain B.
Or is Kerberos or something involved here so this is not possible?
Not sure if I'm explaining myself very clearly.
We could have potentially used Check Point EndPoint client instead for access, for which I could specific Domain B DC for authentication, but this client isn't supported to be used from a Terminal Server. That seems to be the key issue in both cases.