The remote mirroring capability on VDS helps you send traffic from a virtual machine running on one host to a virtual machine on another host for debugging or monitoring purposes. As shown in the diagram below, traffic from a monitored VM on Host 1 is sent through multiple physical switches to an Analyzer VM on Host 2. For this setup to work, you have to perform configuration at various levels as shown by the numbered red circles in the diagram.
Tag Archives: Port Mirroring
In the last post I covered the configuration of one of the port mirroring session type, Switch Port Analyzer (SPAN) on a host. SPAN is a simple configuration on VDS that allows users to quickly replicate traffic to another virtual machine on the same host. However, SPAN on VDS has following limitations
- The source and destination ports of the session should be on the same host. Thus limiting the visibility to a particular host.
- If the monitored virtual machine is moved from one host to another using vMotion, you can’t monitor that virtual machine traffic anymore.
The Remote SPAN (RSPAN) port mirroring session addresses above concerns and also provides the capability to send mirror traffic to a central analyzer tool. The analyzer tool can be connected multiple hops away in a network as shown in the diagram below.
Network troubleshooting and monitoring tools are critical in any environment. Especially in data centers where you have many applications or workloads consolidated on server virtualization platforms such as vSphere. When you ask any network administrators, what are the challenges in troubleshooting data center networks, where server virtualization is prominent? They will say that they don’t have the visibility into virtual networks and they don’t know what is going on in the hypervisor world.
To provide the right amount of visibility to the administrators, VMware vSphere Distributed Switch (VDS) supports industry standard features such as port mirroring and NetFlow. These features were introduced with the release of vSphere 5.0. In this latest release there are more enhancements to the features along with configuration workflow improvements. I will provide more details on the different types of port mirroring capabilities and which one to choose while troubleshooting or monitoring your network.