Zabbix 4 Network Monitoring - Third Edition

Quoting in calculated items

The items we referenced had relatively simple keys: one or two parameters and no quoting. When the referenced items get more complicated, it's a common mistake to get quoting wrong. That, in turn, makes the item not work properly or at all. Let's look at the formula that we used to calculate free disk space:

last("vfs.fs.size[/,total]")-last("vfs.fs.size[/,used]") 

The referenced item keys had no quoting. But what if the keys have the filesystem parameter is quoted like this:

vfs.fs.size["/",total] 

We would have to escape the inner quotes with backslashes:

last("vfs.fs.size[\"/\",total]")-last("vfs.fs.size[\"/\",used]") 

The more quoting the referenced items have, the more complicated the calculated item formula ...