Managing Active Directory Sites and Troubleshooting Replication

When I first learned about Active Directory sites, the concept was explained to me as being locations of readily-available connectivity.

There's an easy analogy for it: islands. In island states, people live on islands, but not everything people need might be available on their island. Additionally, something on their island might break and there are only a few trade routes for goods and services.

In this analogy, the trade routes between geographical locations are the networking connections between Active Directory sites, the islands of readily-available connectivity. The island's roads are that readily-available connectivity: you can use them all you want, without additional cost.

Not many organizations place the domain controllers that hold Flexible Single Master Operations (FSMO) roles in poorly-connected Active Directory sites. Many networking topologies for organizations feature a hub-and-spoke layout with a central location and several outlying locations with, optionally, further outlying locations.

This chapter serves up the following recipes:

• Creating a site
• Managing a site
• Managing subnets
• Creating a site link
• Managing a site link
• Modifying replication schedules
• Creating a site link bridge
• Managing bridgehead servers
• Managing the Inter-site Topology Generation and Knowledge Consistency Checker 
• Managing Universal Group Membership caching
• Working with repadmin.exe
• Forcing replication
• Managing inbound and outbound replication
• Modify the tombstone lifetime period
• Managing strict replication consistency
• Upgrading SYSVOL replication from File Replication Service to Distributed File System Replication
• Checking for and remediating lingering objects

Before studying the recipes, we will look at a few points on Active Directory sites and recommendations.