Chapter 5. Hosts

Table of Contents

5.1. Statistics
5.2. Charts
5.2.1. Physical host charts
5.2.2. Virtual host charts
5.2.3. Using the legend to select one counter

Network convergence, virtualization and cloud computing blur the line between network and system management. To understand performance in this environment you need to monitor both network and server resources. The Host sFlow standard, http://www.sflow.org/developers/specifications.php, defines the physical and virtual server performance metrics that a Host sFlow agent exports using the sFlow protocol. The Host sFlow agent provides scalable, multi-vendor, multi-OS performance monitoring with minimal impact on the systems being monitored.

For information on configuring host sFlow agent, see Appendix B, Configuring hosts to send sFlow.

The Hosts tab presents host performance statistics for hosts that are sending Host sFlow to sFlowTrend-Pro. This tab includes two sub-tabs providing different views of the host performance data:

Statistics
This sub-tab allows you to and compare performance of all servers, virtual-machines and clusters across the whole network. See Section 5.1, “Statistics”.
Charts
This view allows you to trend performance metrics for any individual server or virtual-machine. See Section 5.2, “Charts”.

The ability to directly relate server performance to the corresponding network traffic is a key element in unifying network and system management.

5.1. Statistics

The Statistics sub-tab allows you to compare performance of all hosts over the last minute. Use the View selector to select the group of performance metrics (CPU, Memory, Disk, Network) of interest.

The selected performance metrics for the last minute are displayed in a sortable, hierarchical table, with one row for each host. Physical hosts are shown at the top level of the hierarchy. If the virtual-machines of a physical host are being monitored with sFlow, you can view the performance metrics for the virtual-machines by expanding the physical host.

This view is useful for comparing the current performance of hosts. For example, to compare the CPU utilization of all the hosts, click with the left mouse button on the % CPU column heading, to sort the hosts by CPU utilization.

To view the trend in performance for a host, click with the left mouse button on the row of data for that host. The tab will then change to the Charts sub-tab, showing a trend of the performance metrics for the selected host for the last hour.