I'm currently looking for a solution to monitor our server environment which is made up of mainly Windows 2000 & 2003 servers with a few unix systems mixed in. All together we have around 60 servers that we need to have monitored. We are currently using a free unix based application (Nagios) which is proving to be difficult to manage. The technical person who brought this product in is no longer with us and we do not have a dedicated Unix person on-site. I've already worked with BMC Patrol and had some bad experiences with the server side piece in terms of resources needed for the agent. I am looking for a good windows based monitoring tool that is easy to configure and won't take up a lot of resources on the server end. Any input would be appreciated.