Enabling Fail Over

We recommend enabling the Fail Over option in Exchange environments.

Enabling the Fail Over option enables Location Based FQDNs to select the most appropriate site for requests in the event that the best match is not available. When the Fail Over option is enabled, if a request comes from a specific region and the target is down, the connection will fail over and be answered with the next level in the hierarchy. If this is not available, the connection is answered by the nearest (by proximity) target. If this is not possible, the target with the lowest requests are picked. For example, if a request from Ireland is received, but the site assigned to Ireland is unavailable, a site assigned to Europe is selected. If the site assigned to Europe is also unavailable, a site assigned to Everywhere is selected. If this too is unavailable, the site with the lowest requests of the available sites in the same continent is selected using the round robin method. The Fail Over setting affects all targets. The Fail Over option is only available when the Selection Criteria is set to Location Based.

Fail Over is set on all GEO nodes. If a partner GEO unit has been configured, you can assume that all nodes are operating on the same configuration. The settings in one GEO is synced to all other GEO nodes.