In Zabbix, if an item's key is not unique, what is the consequence?

In Zabbix, if an item's key is not unique, the data for that item may be overwritten. This means that when multiple items share the same key, each new piece of data collected for that key will replace the previously collected data. This behavior occurs because Zabbix associates the item key with a specific metric for a specific host and does not maintain a history of past values if multiple entries with the same key exist.

Having a non-unique item key can lead to loss of valuable monitoring information, as the latest incoming data will simply erase earlier values rather than allowing them to co-exist. This emphasizes the importance of defining unique item keys for each metric you wish to monitor, ensuring that each piece of data is stored and can be accessed later for analysis, reporting, or alerting.

Ensuring uniqueness in item keys helps maintain the integrity of your monitoring setup and prevents loss of data, which is crucial for effective problem detection and performance monitoring in IT environments.