Description:The Exchange services not able to restart and have the following event logs
Event ID: 10006
Source: MSExchange Mid-Tier Storage
Description: Active Manager Client experienced an AD timeout trying to lookup object '' in 00:01:00.
Event ID: 2142
Description: Process Microsoft.Exchange.Directory.TopologyService.exe (PID=) Forest Domain.com. Topology discovery failed, error details. No Minimal Required Number of Suitable Directory Servers Found in Forest Domain.com Site RNS and connected Sites..
Misconfiguration of the Active Directory Global Catalog as we have two options in order to make the Active directory work properly with Exchange which is at the same AD site:
Option 1: Have one Global Catalog server for Each site
Option 2: Have all Active Directory servers a Global Catalog
So incase we have four AD in the same site we cannot have only three of them Global Catalog servers.
Make sure you have correct number of the Global Catalog servers at this site