Managing DNS failover

HCP replication helps ensure continuous namespace availability. If a system in a replication topology fails, client requests for access to a replicated namespace can be serviced by other systems in the topology.

You can use the HCP DNS failover feature to automate the process of redirecting client requests from a failed system to a healthy one. For active/active links, this process can be automated in other ways as well. Automating redirection means that applications do not need to be modified to explicitly direct requests to another system when the normally targeted system fails.

The DNS failover feature requires that the HCP systems involved use a shared DNS for system addressing. If the systems don’t use a shared DNS, DNS failover is not an option for automating redirection of client requests.

An HCP system can service automatically redirected requests only if the target namespace is configured to support service by remote systems. If the namespace is not configured this way, requests to access the namespace on a failed system fail.