Custom facts

Facts are the most comfortable kind of variables to work with:

• They are at top scope, therefore easily accessible in every part of our code

• They provide direct and trusted information, being executed on the client

• They are computed: their values are set automatically and we don't have to manage them manually.

Out-of-the-box, depending on Facter version and the underlying OS, they give us:

• Hardware information (architecture bios_* board* memory* processor virtual)

• Operating system details (kernel* osfamily operatingsystem* lsb* sp_* selinux ssh* timezone uptime*)

• Network configuration (hostname domain fqdn interfaces ipaddress_* macaddress_* network*)

• Disks and filesystems (blockdevice_* filesystems swap*)

• Puppet related software versions (facterversion puppetversion ruby*)

We already use some of these facts in modules to manage the right resources to apply for our operating systems, and we already classify nodes according to their hostname.

There's a lot more that we can do with them,...