3. GFI Network Server Monitor
Network Server Monitor checks your network & servers for failures and fixes them automatically, before your network users notice them! Alerts can be sent by email, pager or SMS. You can reboot a machine, restart a service or run a script, batch job or executable. GFI Network Server Monitor is easy to use and competitively priced.
Built-in monitoring rules: Exchange Server, SQL server, Oracle, ODBC, CPU usage, FTP & HTTP, File Existence, etc. You can write custom monitor functions in VBscript (use ADSI/WMI)
Supported by: All Windows Server products