70-294 Concepts: Active Directory Site Links

When designing Active Directory Site Links:

  • On non-fully IP routed networks, disable automatic site links, implement a site link bridge
  • A site link is a set of sites which communicate at the same cost, and can be automatically configured to route in a redundant path between sites within a site-link
  • In a fully routed network, you do not need site link bridges unless you wanted to specifically control the flow of replication changes.
  • Controls which sites are connected and at what cost, but does not directly control which servers replicate with one another, this would be the role of a Preferred Bridgehead Server
  • Best Practice to create site links from corporate to branches, little benefit in having a tiered site line corp->branch->branch
  • You cannot create site-links between networks which are not IP routed
  • Site link bridging is used when an IP network is not fully routed; or if replication is not converging properly (used when site’s are 2+ hops away)
  • Site links are for same domain only, and are between IP-routable networks unless you use a ip bridge to connect two non-routable network in the same domain;
  • If two non-routable domains are separated by a site in a different domain, you will need to have a DC setup in that site or you will need a routable network
  • IP Replication for single domain sites; SMTP not available