When a new server is added to the network is there a way to automatically create a hostalive object?
you can write a script which scans the network and creates the object - e.g. via REST API.
Or you’ll have automation with Puppet etc. in place which automatically generates monitoring objects for example. The possibilities are nearly endless - you’ll just need to define a way how to do it. Best is to hook into the deployment process of such a new host and have monitoring as an integral part after the initial installation. We do that in our infrastructure with Foreman and Puppet for ourselves and our customers for example
We use netbox for this. To add a machine, you need to allocate it an IP, which you do in Netbox, then the netbox Icinga Director job kicks in, imports it in to Icinga and you get all the checks that are relevant for it, including tags etc.
Director can also use vmware etc for automatic import/setup of monitoring of course.
I have a standard-host-template which includes the hostalive check and is the first import every host gets