VSphere 5 network function: NetFlow Configuration

NetFlow is a network protocol that collects IP traffic information as records and sends them to collectors such as CA NetQoS for traffic analysis. Vmware vSphere 5 supports NetFlow v5, the most common version supported by network devices. The NetFlow feature on the vSphere 5 platform provides visibility into virtual infrastructure traffic, including:

Traffic from virtual machines on the same host and from virtual machines)

VM traffic between hosts is the traffic from virtual machines on different hosts to virtual machines)

Traffic from virtual machines to physical infrastructure

A Distributed switch is displayed, Which is configured to send NetFlow records to the collector connected to an external physical network switch. The blue dotted arrow indicates the NetFlow Session, which is created for sending traffic records to the Collector for analysis.

Usage

The NetFlow function of the distributed switch and the NetFlow collector tool can monitor application traffic and measure traffic performance over time. They can also help with capacity planning, ensure that I/O resources are allocated to the application according to the needs of different applications.

If the IT administrator wants to monitor the performance of application traffic running in the virtual environment, he can enable traffic monitoring in the distributed switch.

Configuration

The NetFlow of a distributed switch can be enabled at the port group layer, individual port layer, or uplink link layer. When configuring NetFlow on the port layer, the administrator should select the NetFlow overwrite label, which ensures that the traffic can be monitored when NetFlow is disabled on the port group layer.

The following NetFlow configuration diagram shows different parameters that can be controlled during the configuration process.

1. Configure the IP address and port in Collector Settings according to the information of the Collector tool installed in your environment.

2. Advanced Settings) allows you to control traffic timeout and sampling rate. To change the amount of information collected for a certain traffic, you can change the sampling rate. For example, if the sampling rate is 2, it means that VDS will collect data every other packet. You can also modify the idle stream timeout value.

3. When you want to see that the collector tool is a part of a vds ip address, rather than managing network IP addresses as a separate host), the vds ip Address Configuration is very useful. In this example, because no vds ip address is entered, the collector tool provides traffic details for each host to manage network IP addresses.

If you only want to monitor the Internal traffic of the virtual infrastructure, check the "Process Internal flow only" box.

I am often asked about the impact of enabling the NetFlow function on the CPU. The answer in this article is that it depends entirely on the traffic volume in your environment and the traffic running rate. If you think your environment has a lot of traffic and are worried about CPU resources, you can use the control provided in NetFlow settings to select the traffic to be monitored. For example, you can change the sampling rate or choose to monitor internal traffic only. Additionally, you can enable or disable NetFlow for port groups or ports.

As customers begin to virtualize applications, they will need appropriate tools to manage SLA requirements for these applications. The NetFlow function of the vSphere 5 platform can monitor these application flows and plan the capacity of network resources.