Q&A with Ran Nahmias of Net Optics

VSM: What is the difference between network monitoring of physical environments and network monitoring of virtual environments?

RN: Physical networks are tangible and made of assets connected by network cables. The “fixed” nature of physical environments makes monitoring predictable and therefore easy. The locations of computing devices as well as the path of packets are all predictable – making total visibility and monitoring simple.
However, in virtual environments, the picture is different. The only physical assets are the hypervisor hosts where many computing machines are running in virtual stacks. The virtual machines are inter-connected via virtual networks, switches and backplane hardware. The virtual networking of hypervisors is such that traffic traversing in virtual networks is invisible to the physical tools (that reside on the physical networks) and requires other means of monitoring. The elasticity of virtualization, where hosted virtual machines can be moved between physical hosts (or geographical location) at any given moment, complicates the feasibility and effectiveness of existing monitoring solutions.

VSM: What are some of the biggest pain points faced by data centers that have moved to the cloud?

RN: Data centers that have adopted virtualization and cloud technologies are facing numerous issues. The first challenge is scope – a data center that in the physical world can host 100 servers, can now host 100 hypervisors with 10-15 virtual servers on each. The switch from 100 machines to anywhere between 1,000 - 2,500 machines is a dramatic transition.

In many cases, the personnel and infrastructure are not always up to the task of managing this growing capacity. Networks, networks devices and instrumentation layer tools all need a thorough upgrade to meet the new requirements. Many tools– starting with switches and extending to routers and inspection, recording and other tools commonly used in data centers – cannot support the increased capacity.

Even in the event that the infrastructure has been architected to meet the sheer volumes of traffic, a lot of this traffic is hidden from the physical networks because machines are no longer in a static location and the daily operations are shaped differently. SLAs are more complex and require a different skill set to maintain and guarantee maximum up time. Visibility into the virtual networking layer can help in troubleshooting and recovery.

VSM: What main benefits has the move to virtual networks brought to data centers?

RN: The push toward virtualization and cloud is driven by a variety of beneficial factors including space and power saving, and a reduction in environment emissions. These financial benefits coupled with the elasticity and sustainability of virtualized environments present total benefits that are unmatched when compared to a physical environment. When virtualizing computing workloads, organizations see great improvement in every functional aspect with very few drawbacks.

VSM: What are the three main things customers should look for when searching for a monitoring solution for their virtual environments?

RN: First and foremost, customers should seek total visibility that is consumable by their systems and tools of choice. Many existing solutions are purpose built to complement a specific set of tools or functions – limiting or eliminating the customer’s “freedom of choice” when it comes to consuming the monitored traffic.