I have just started to a dabble with a Icinga2 Server (still running Icinga1 productively).
The first task I have set myself is getting the Cohesity Plugin (https://github.com/cohesity/cohesity-nagios-plugin) to run.
Is there existing documentation which guides a user coming from Icinga1 how to set his Check Commands, Hosts and Services using Icinga2? My plan is to roll the configs out using Ansible, so no Director involved.
I think that the existing documentation around creating hosts and services enough – Coming from 5 years of Naemon and Nagios core before moving to Icinga, you mostly just need to figure out the syntax and additional features, since they’re all based off of Nagios and are almost interchangeable.
You could check out these docs around migration to see if there’s anything in there that could be of use to you.
A good read is in the Migration section of the Docs: Migrating from Icinga 1x - Icinga 2
This should give you an idea about how it looks like and what has changed. The biggest change is going from an object-oriented configuration (Icinga 1/Nagios) to a rule-based one (Icinga 2), this requires a change in the mind-set.
Then I would recommend considering the Director as graphical frontend and for automated configuration. This could be another hard switch in the mindset, but also a great benefit as having a rule-set defined in a quite readable format and then automatically importing hosts and users as the most frequently changing objects is really reducing the time need for maintaining the environment so more time to spend on improving it instead.