All Hiera backends using the :datadir configuration, in particular the both
default backends yaml and json are limited to just one datadir.
Furthermore, only one instance of each backend can be used and configured.
Although there is #1394 and multiple requests for it on mailing lists, Puppetlabs until now hasn't decided to fix it.
After looking at the Hiera code, I know why. They would have to rewrite a
buch of code. This is a quick hack that (unfortunately) duplicates some
code from the yaml backend. Avoiding the evilest monkey patching I could
imagine, this was the only option.
Install the gem using:
$ gem install hiera-multiyaml
And use it in your hiera.yaml like this:
:backends:
- multiyaml
:multiyaml:
:backends:
- firstyaml
- secondyaml
:firstyaml:
:datadir: /etc/puppet/environments/production/data
:secondyaml:
:datadir: /var/lib/hiera
Please note that the datadirs will be processed and merged sequentially in
the order you specify them. This is exactly the same behaviour as the
:hierachy configuration option.