“Virtualization is an insurance policy…”
Can Virtualization Work for You?
Companies considering virtualization should consider the following four steps to get started:
1. Talk to a Lynbrook Systems Architect about the benefits of virtualization and learn best implementation practices.
2. Conduct an ROI analysis using a free online tool, such as the VMware ROI calculator.
3. Use free tools to get started, such as VMware ESXi, VMware Converter and VMware Go.
4. Start slowly by virtualizing smaller application workloads, such as file, print and web application servers, to become comfortable with virtualization before tackling more critical line of business apps and database servers. In the end, most, if not all, of your server-based application workloads will be great candidates for virtualization.
Virtual Networking Components
The key virtual networking components in a Virtual Infrastructure are virtual Ethernet adapters and virtual switches. A virtual machine can be configured with one or more virtual Ethernet adapters. Virtual switches allow virtual machines on the same host to communicate with each other using the same protocols that would be used over physical switches, without the need for additional hardware. They also support VLANS that are compatible with standard VLAN implementations from other vendors.
Other things to consider:
- Virtual switches do not learn from the network to populate their forward tables. This helps to minimize denial of service attacks.
- Virtual switches make private copies of frame data used to make forwarding or filtering decisions. This ensures the guest operating systems cannot access sensitive data once the frame is passed onto the virtual switch.
- VMware technology ensures that frames are contained within the appropriate VLAN on a virtual switch 1) by carrying the data outside the frame as it passes through the virtual switch, and 2) because there is no dynamic trunking support that could open up isolation leaks, making the data vulnerable to attack.
Virtual Switches vs. Physical Switches
Virtual switches are similar to modern physical Ethernet switches in many ways. Like a physical switch, it maintains a MAC:port forward table and performs frame destination lookup and frame forwarding. It also supports VLAN segmentation at the port level, so that each port can be configured as an access or trunk port, providing access to either single or multiple VLANs.