Users only log into the server, they don't actually ever truly log in to a collector as far as AppMon is concerned. This plugin is only reading from the Server.0.0.log file for AppMon user account logins so it doesn't see things like OS user logins to a collector box.
This is saying that for the monitor configuration it must be set to run from a local collector on the same host as the server. I imagine this is because it was built to check on the local host for the Server.0.0.log file which has the login information and doesn't support remotely logging into the Dynatrace server to view that log which is what would need to be done if it was on a remote collector.
Monitors have to be run from a collector, and this one will only work if it is run from the local collector instance. I think by default there will be a local collector running.
This is a monitor type plugin so that is required. Once you've installed the plugin to the sever (via the client) you go into any system profile and in the monitors tab set up a new monitor and select this plugin and fill in the configuration with your information. You'll also select a schedule (how often the monitor runs) and an execution location which is the collector that will run the monitor (this will need to be the local one as discussed above).
Thanks @James K. this helps. Two questions:
1. So if there are agents from multiple collectors in one system profile, I will need to create multiple monitors in that case?
2. Also if the client is installed on my machine wheres as server and collector are installed on a separate box, how do I specify the server log path in that case?