VSphere 5 network function: Port Image

A port image is a network switch that sends a copy of the network packet on a switch port to a network monitoring device connected to another switch port. On a Cisco switch, a port image is also called a Switch Port Analyzer SPAN ). In Vmware vSphere 5, a distributed switch provides a similar port image function that can be used for physical network switches. After the destination virtual machine, vmknix, or upstream port is configured in the port image Session, the distributed switch copies the data packets to the destination.

Port images provide the following visibility:

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)

Displays the different traffic types that can be monitored by a virtual machine on a host as a destination or monitoring device. All traffic shown by the Orange dotted line arrows is the volume of image traffic sent to the target virtual machine.

The name definition of the entry source and exit source is related to VDS. For example, when you want to monitor the traffic sent from a virtual machine to VDS, it is called the incoming source traffic because the traffic tries to enter VDS. If you want to monitor the traffic received by the virtual machine, configure the port image session by exporting the source traffic source, as shown in the upper-right corner.

The name definition of the entry source and exit source is related to VDS. For example, when you want to monitor the traffic sent from a virtual machine to VDS, it is called the incoming source traffic because the traffic tries to enter VDS. If you want to monitor the traffic received by the virtual machine, configure the port image session by exporting the source traffic source, as shown in the upper-right corner.

If the network administrator is worried about the impact of image traffic on normal traffic, they can select a separate upstream port to send image traffic. Shows the process of using a separate upstream port to send image traffic.

Usage

The Port Mirroring function of a distributed switch is a valuable tool that helps network administrators solve Network Problems in virtual infrastructure. Fine-grained control over all traffic at the port entry and exit can also help the Administrator determine which traffic is sent for analysis.

Configuration

The port image configuration can be completed at the distributed switch layer. Here, the network administrator determines the traffic source to be monitored and the traffic destination to which the traffic is mirrored to create a port image session. The traffic source can be any port with any entry, exit, or all selected traffic, and the traffic destination can be any virtual machine, vmknix, or upstream port.

This is the first step in the port image session configuration process. In this step, you can define the name of the port image session and select whether to allow normal I/O on the target port. They can also select a VLAN in the Encapsulations VLAN box to encapsulate these image packets.

After you click Next, the configuration dialog box will let you select the source you want to monitor. Based on the traffic type you want to monitor, you can select Ingress, Egress, or Ingress/Egress from the traffic drop-down menu, as shown in ). Then, specify the Port ID of the specific source VM. To obtain the corresponding dvPort number or Port ID of the VM, follow these steps:

1. Home> directory> network view

2. Select dvSwitch and select the port option on the right panel, scroll down to view the Virtual Machine and related port ID

Enter the Port number in the Port ID box, move it to the right panel, and then click Next.

In the next step, you can select the destination of the image traffic you want. There are two options in the drop-down menu of the destination, as shown in.

This completes the creation of the port image. As shown in, you can find the detailed information of the image session on this port and see that the session status is disabled.

To enable this port image session, click "Edit". A dialog box is displayed. Select enable in the status bar, as shown in. This enables the port image session, and VDS will mirror the traffic to the selected target port.