About xHA - BlueCat Address Manager - 9.1.0

Address Manager Administration Guide

prodname
BlueCat Address Manager
version_custom
9.1.0

BlueCat Crossover High Availability (xHA) provides disaster recovery through the use of redundant servers: xHA makes two DNS/DHCP Servers function as a single server. If one of the servers fails for any reason, the other takes its place and continues providing services.

The pair appears as a single server for DNS queries because both servers share an IP address. Each server in the pair has its own IP addresses for management through Address Manager.

Supported xHA pairs

  Hardware appliance 2 Virtual machine 2
Hardware appliance 1 xHA supported xHA not supported
Virtual machine 1 xHA not supported xHA not supported*

Supported xHA configurations

  Physical pair Virtual pair
xHA Backbone connection between pair (eth1) Highly recommended Highly recommended
Different software versions on each node Not supported Not supported
Different architecture on each node Not supported Not supported
w/ non-BlueCat failover enabled** Not supported Not supported
Note: *Only supported where latency between the two virtual machines is roughly equivalent to two physical appliances and where the two virtual machines are not on the same physical hypervisor host. If the latency between the virtual xHA pairs exceeds that of two physical appliances, BlueCat recommends foregoing xHA in favor of the failover capability provided by the hypervisor (if one exists), though we may not officially test/support such features. **Such as VMware vMotion or Fault Tolerance.