Moves and Changes
Moves and Changes It's relatively easy with physical systems to understand the interdependencies of various applications because the systems are often kept in close physical proximity to one another. With virtual systems, the interdependencies may not be as obvious. It's therefore important to have a plan for tracking dependencies and where interdependent systems move in the physical infrastructure.Desired Configuration In October, the Center for Internet Security released its first benchmark for securing VMware's ESX Server 3.x. According to CIS, "the benchmark is a compilation of security configuration actions and settings that -harden' virtual machines." Many longstanding configuration management vendors, including Configuresoft, provide management tools that check desired-state configuration against actual configurations for physical and virtual systems. Consider that VMs share physical resources. Systems that require stringent security configuration should be co-hosted on the same physical hosts to prevent low-priority virtual servers that may not be as diligently cared for from taking shared physical resources from high-priority virtual servers. Connect the dots between physical and guest systems and ensure that configuration management on both types of systems is in place to help manage a virtualization rollout.
Understand the policies that enable the creation and movement of virtual systems. Losing control of virtual server positions as the result of moving a virtual system to another physical host to improve performance can lead to sprawl. Most virtualization platforms include the ability to monitor virtual server performance and the availability of physical compute resources. When a VM reaches a predefined high utilization rate, the allocation module can move virtual systems to physical hosts with more available power. It is up to IT managers to monitor this process and ensure that virtual server resources are accounted for, regardless of the physical host where the virtual system currently resides.