Low-level discovery provides a way to automatically create items, triggers, and graphs for different entities on a computer. For instance, Zabbix can automatically start monitoring file systems or network interfaces on your machine, without the need to create items for each file system or network interface manually.

In Zabbix, four types of item discovery are supported out of the box:

• discovery of file systems;
• discovery of network interfaces;
• discovery of CPUs and CPU cores;
• discovery of SNMP OIDs.

A user can define their own types of discovery, provided they follow a particular JSON protocol.

vfs.fs.discoverynet.if.discovery就是zabbix自带的自动发现键值，能够自动识别agent端的文件挂载情况和网卡信息。还有基于SNMP OID的自动发现键值，能够自动识别交换机的所有端口信息。

### 实现步骤：

#### 3.检测自定义键值

zabbix server端测试：

LDD官方文档