Physical device management:
All of these devices support the basic SNMP MIBS for host resources and Cisco hardware MIBs. You should configure an SNMP monitoring solution to ensure that memory, hardware, and CPU are all within well defined parameters. I would recommend a SNMP monitoring solution that baselines these metrics and provides alerting capabilities to alert you if the CPU, Memory, etc exceed a defined baseline or threshold. By using a baseline, you would be able to alert without a prescribed best practice for hardware requirements.
Voice device management:
The 3845 routers support NetFlow. It would be an excellent opportunity to monitor your routers and switches using NetFlow. You can then use the reporting features to understand the capacity and flow utilization of the VoIP impact to the network at large.
Alternatively, the VG224's and MCS 7800 series also support some specific voice gateway MIBS. These MIBs provide specific VoIP details related to call status. You should be able to leverage the same SNMP reporting tool to ensure that call volumes, call rate, and VoIP delay factors are reported. Any trends that indicate an abnormal call volume or specific error conditions would ensure that you are alerted proactively regarding potential issues.
You can always identify which MIBs are supported by the specific devices by using Cisco's MIB locator utility. In newer versions of code, Cisco is moving toward a new API architecture, but it doesn't appear that the specific devices listed are part of that new program just yet.
This was first published in September 2009