This page is to serve as a focal point for discussion and methods for making Zabbix run in an HA environment.
Methods:
Both nodes share the load for monitoring. If one node goes down the other will take up the slack.
Both nodes must be designed to handle the 100% of the load
Active/Active can be a gateway to scale out to a Active Cluster configuration
Presently Active/Active is not possible with Zabbix without many modifications.