We have a AD trust established between two forests. It is working fine except that on one DC there are event logs (event ID 83 in Operations Manager log) generated. It contains:
AD Monitor Trusts : The trusts between this domain (<domain_name1>) and the following domain(s) are in an error state: <domain_name2> (inbound).
The error is: The specified domain either does not exist or could not be contacted. (0x54B)
There is a firewall between only this one DC and trusted domain DCs. I am wondering whether all domain controllers in both forests must have a connection to each other or it is ok that only some DCs (all except this one) from one forest have connection to all DCs in trusted domain?