Now that we have a basic understanding of the frontend navigation, it's time to look at the basics of data gathering in Zabbix Items. In general, anything you want to gather data about will eventually go into an item.

If items are so important in Zabbix, we should create some. After all, if no data retrieval is possible without items, we can't monitor anything without them. To get started with item configuration, open Configuration | Hosts. If it's not selected by default, choose All in the Group drop-down menu (in the top-right corner). This is a location we will visit quite a lot, as it provides easy access to other entity configurations, including Items and Triggers. Let's figure out what's what in this area. The most interesting functionality is the host list:

Primarily, it provides access to host details in the very first column, but that's not all. The usefulness of this screen comes from the other columns, which not only provide access to elements that are associated with hosts, but also list the count of those elements. Further down the host entry, we can see a quick overview of the most important host configuration parameters, as well as status information, which we will explore in more detail later:

We came here looking for items, so click on Items next to the Zabbix server. You should see a list similar to the one in the following screenshot:

Note the method we used to reach the items list for a particular host—we used convenience links for host elements, which is a fairly easy way to get there and the reason why we will use Configuration | Hosts often.

Back to what we were after, we can see a fairly long list of pre-existing items. But wait, didn't the Zabbix status screen that we saw in the first screenshot claim there's a single host and no supported items? That's clearly wrong! Return to Reports | System Information (or Monitoring | Dashboard, which shows the same data). It indeed shows zero supported items. Now, move the mouse cursor over the text that reads Number of items (enabled/disabled/not supported), and take a look at the tooltip:

Aha! So it counts only those items that are assigned to enabled hosts. As this example host, Zabbix server, is disabled, it's now clear why the Zabbix status report shows zero items. This is handy to remember later, once you try to evaluate a more complex configuration.