Writing Hiera data
As we've seen, Hiera data is stored in text files that are structured using the format called YAML (short for YAML Ain't Markup Language), which is a common way of organizing data. Here's another snippet from our sample Hiera data file (hiera_sample.yaml):
---
...
syslog_server: '10.170.81.32'
monitor_ips:
- '10.179.203.46'
- '212.100.235.160'
- '10.181.120.77'
- '94.236.56.148'
cobbler_config:
manage_dhcp: 1
pxe_just_once: 1There are actually three different kinds of Hiera data structures present: single values, arrays, and hashes. We'll examine these in detail in a moment.
File header
YAML files begin, like the previous example, with three dashes and a newline (---). This is part of the YAML format, not a Hiera feature; it's the syntax indicating the start of a new YAML document.
Single values
Most Hiera data consists of a key associated with a single value, as in the previous example:
syslog_server: '10.170.81.32'
The value can be any legal...
