Expanding Windows SNMP Monitoring
Simple Network Monitoring Protocol (SNMP) is a protocol designed to be the eyes and ears for the System Administrator by providing a standard interface that can be used to monitor all manner of items connected to a network. Not only can SNMP monitor, it can also alert System Administrators to elements of their environments that are operating outside of their threshold. It was for these reasons I recently installed the Microsoft SNMP agent on my own Windows 2003 server, however I had forgotten just how limited the scope of the Microsoft SNMP agent was. While there are no problems for support of the basics such as CPU, memory, hard disk & network utilisation, and even some really cool metrics for specific system services such as IIS, I found it lacking when trying to dig a bit deeper.
Amongst some of the core metrics you would want to measure to keep an eye on the general health of your system which the standard Windows SNMP agent does not support are the pages/sec value for your memory subsystem, and the average disk queue length of your physical drives. These, and many other metrics (particulary with hardware monitoring) are unfortunately absent from the Windows 2003 SNMP agent. However, after a bit of searching around I found that this does not need to be the case. SNMP-Informant is an SNMP extension agent for Windows which greatly expands the SNMP monitoring capabilities of Windows. While to get the best out of what SNMP-Informant have to offer you'll need to purchase one of their agent packages, they do have a free offering. The SNMP Informant - Standard Agent includes over 60 SNMP items concentrated in the area of CPU, memory, hard disk and network (including the pages/sec and average disk queue length metrics mentioned early). Using this extension agent and the standard Windows 2003 agent you should find you are able to monitor just about all the items you need to keep a good general overview of your systems health.