Currently HA documentation is very hard to understand for new user - https://www.zabbix.com/documentation/6.0/en/manual/concepts/server/ha

Proposed a set of improvements.

1. Add high level overview - what is HA in Zabbix and  what problems it can solve.

2. Real life scenario - step by step setup:

• Agent, Agent2 and Proxy configuration for HA.
• (blocker) During upgrade from 4.4 the an IP address should be removed from Frontend configuration. In 6.0 IP read from DB. 
• Log outputs of HA and what it means.
• Screen shots required.