This is an old revision of the document!
While generally OK events close all problem events in Zabbix, there are cases when a more detailed approach is needed. For example, when monitoring log files you may want to discover certain problems in a log file and close them individually rather than all together.
This is the case with triggers that have Multiple Problem Event Generation enabled. Such triggers are normally used for log monitoring, trap processing, etc.
It is possible in Zabbix to relate problem events based on the event tags. Tags are used to extract values and create identification for problem events. Taking advantage of that, problems can also be closed individually based on matching tag.
In other words, the same trigger can create separate events identified by the event tag. Therefore problem events can be identified one-by-one and closed separately based on the identification by the event tag.
While correlation can be defined on the level of one trigger, it is also possible to relate separate triggers using global correlation rules.