I have a new exchange server setup as follows- 2 Domain controllers which are also DNS servers1 Exchange server with Client Access and Hub Transport role1 Exchange server with mailbox role Every few hours we are getting issue where we cant send mail and cant use teh management console, it comes up with the error "Could not find any Domain Controller in doman domain.local" This also happens if you try and setup the configuration domain controller. Both exchange servers have the local DNS servers as primary and secondry, with internet DNS servers after that. I even tried setting up a secondry DNS server on the Exhchange server, but that doesn't help.

Have you run dcdiag tool ? please reference this kb http://support.microsoft.com/kb/905900/en-us