Server Setup Server virtualization brings industrial production to the data center. One key to industrial design is placing a premium on creating products that are cost-effective in mass production.One of the best ways to ensure that servers are correctly configured and easily maintained is to provide business managers with enough standard configuration choices to satisfy most of their application needs and to disallow the return of handcrafted server customizations that drive up the amount of maintenance labor time. Implement a resource SLA (service-level agreement) as part of virtual server instantiation. Go as far up the organizational chart as necessary to get an authoritative decision on which applications will be preordained winners and losers in the event of a contest for available physical resources. Be ready to offer suggestions based on application type. For example, order processing and the associated database systems are easy candidates for a guaranteed high SLA because they (presumably) conduct high-value transactions. Create only the number of systems needed to adequately support an application. For organizations that are new to virtualization, and where there are virtualization skeptics, plan on allowing at least six months to prove the reliability of the virtual system creation process. If IT managers can show business managers that creating servers as needed based on actual performance reports works, then it will be possible to right-size applications from the get-go. For organizations that forecast IT budgets based on capacity trends, it is especially important to accurately measure server use. It is also important to ensure that system owner information is up-to-date. The ease with which virtual systems can be created also makes it easier for server owners to forget about these VMs. Unlike physical systems that require an extensive budget process, a physical implementation, an accounting depreciation and sometimes lease company accountability, virtual systems can easily sit forgotten and unaccounted for. Aside from taking up virtual processing overhead, these forgotten systems soak up management cycles because they must be updated. Further, idle virtual systems can be a security hazard. One of the great timesavers of a virtual infrastructure is the ability to instantiate new servers by cloning an existing system, and it's important that new systems are cloned from approved images. It may be quicker to clone a VM from one already in production, but tracking the lineage of that system to ensure it has the right security patches and service configurations is extremely difficult. Also consider that a VM cloned from a system operating in one part of your network may not be correctly configured to operate in another part. For example, an internal Web portal system that gets cloned and placed in a DMZ would be a sitting duck.
In the case of server virtualization, IT managers should create a catalog of standard server configurations from which business managers can choose to install new applications. For example, Option A could be a single-processor system with 2GB of RAM and 10GB of storage with a single HA. Option B could be a two-processor system with 4GB of RAM and 20GB of storage. The purpose of creating and enforcing a standard catalog of virtual systems is to prevent customized server sprawl, where each VM is handcrafted for each application. Maintenance costs associated with customized servers can eat up much of the cost savings gained from implementing a virtual infrastructure.