38
38
ENCLOSURES AND RACKS
The popularity of enclosed cabinets The two key reasons for choosing an enclosed cabinet are controlled airflow and security . As the technologies surrounding cloud computing and convergence continue to evolve , the data centre environment will be tasked with supporting these platforms . The increase of equipment density per rack , and its associated cooling requirements , will be on the rise making the enclosed cabinet solution a perfect ally to better control the different dynamics related to airflow management .
With the use of built-in features and specific design geometries it is possible to create an almost perfect separation between hot air and cold air , improving cooling efficiency . Enclosed cabinets offer the best and most simple approach to a variety of air segregation strategies in a totally passive solution . These include :
Ease of access is a key advantage to working with open frame racks as it can drastically reduce the maintenance time required for any moves , additions or changes . It ’ s also worth noting that open frame racks offer the best opportunity to reduce MTTR ( Mean Time To Repair ) which can be hugely beneficial in regards to service level agreements ( SLAs ) since easy accessibility means the time needed to access cabling and equipment is reduced .
Furthermore , while two post open frame racks provide the most efficient use of floor space in the data centre , four post open frame racks are a more suitable choice for supporting larger and heavier equipment . This includes modular network switches because they provide front and rear support and greater stability . Two post open frame racks can be used in most applications , but are usually used with rack mount equipment that ’ s less than 510mm deep .
Finally , open frame racks offer the optimum cable management solution for any given installation . Open frame racks aren ’ t restricted by side panels or walls , so it ’ s possible to use wide and deep vertical cable managers along both sides of the frame , offering the perfect cable management solution . In fact , when combined with advanced vertical cable managers , a 42RU open frame rack can expand density by up to one thousand connections , which is best achieved by using angled patch-panels , for both copper and / or fibre cabling .
Cons of open frame racks Lack of security and poor aesthetics can be a consequence of the cost savings achieved using an open frame rack solution . As the term ‘ open ’ suggests , open frame racks can be accessed easily , which creates a security concern for both accidental and / or intentional damage . Additionally , the active equipment is exposed to dirt and debris that can cause irreversible damage to the fans and the silicon technology . Furthermore , it could be argued that open frame racks don ’ t offer the same degree of aesthetics as enclosed cabinets . With equipment , cables and cable managers all clearly visible , they can create an unsightly appearance , especially if they ’ re poorly maintained .
• Cabinet level containment characterised by a Vertical Exhaust Duct ( chimney ) and combined with specific accessories and defined cabinet geometries to control airflow .
• Cold Aisle Containment defined by an aisle roof and two aisle doors to create a segregated cold aisle environment .
• Hot Aisle Containment created by building a hotaisle exhaust system connected to the return plenum and two aisle doors to form a segregated hot aisle environment .
Enclosed cabinets provide a much higher level of physical security as opposed to open frame racks . Different types of locking systems are available to enhance physical protection from unauthorised entry . Considering that security is a major concern for most data centres , it ’ s not surprising that enclosed cabinets have become the solution of choice in recent years as they offer a much safer environment for hosting sensitive data .
Despite offering a more secure solution , enclosed cabinets can present issues with maintenance operations due to the restricted accessibility . And it goes without saying that cabinets can be cost prohibitive for many data centres , especially for a small operation or start-up .
Making the best choice With IT budgets under constant pressure , even within large organisations , many data centre managers find trying to choose the best strategy to deliver optimum performance within budget a daunting challenge .
When comparing open frame racks to enclosed cabinets , it ’ s important to consider all the factors that will play a major role in the lifetime of the installation and choose the solution that will best serve the core requirements . Fundamentally , an enclosed cabinet will always provide greater security and better control of airflow , but an open frame rack can still be a viable alternative when it comes to housing a moderate amount of IT equipment or used as a main patching frame . Open frame racks are cost-effective , easily accessible and durable , which makes them a sound option for telecom equipment , servers or networking with a relative low power load where cooling requirements are not a major concern . n
www . networkseuropemagazine . com