I have a two way trust forest between two domains in my organization.
My Organization setup as below:
Forest 1 : 6 domain controllers .no firewall between thise domains.
Forest 2: 6 domain controllers . Every two domain in separate locations.
Forest2Domain01&02 in separate location with there clients with firewall in between other domains
Forest2Domain03&04 in separate location with there clients with firewall in between other domains.
Forest2Domain05&06 in separate location with there client with firewall in between other domains.
We have issue with the last 2 domains05&06 which we can't validate the trust with Forest1 RPC Services Unavailable. And i can't add any user from forest1 in any local admin group clients belong to domain05&06. This issue not exist with other 4 domains which i can add and locate users from Forest1.
It was working before but it stopped suddenly .