Black Box Explains...Choosing a cabinet.
Understanding cabinet and rack measurements.
The main component of a cabinet is a set of vertical rails with mounting holes to which you attach your equipment or shelves. When you consider... more/see it nowthe width or height of a cabinet, clarify whether the dimensions are inside or outside.
The first measurement you need to know is the width of the rails. The most common size is 19 inches with hole-to-hole centers measuring 18.3 inches. There are also 23-inch and 24-inch cabinets and racks. Most rackmount equipment is made to fit 19-inch rails but can be adapted for wider rails.
After width, the most important specification is the number of rack units, abbreviated as “U.” It’s a measurement of space available to mount equipment. Because cabinet width is standard, the amount of space is what determines how much equipment you can actually install. Remember, this is an internal measurement of usable space and is smaller than an external measure of the cabinet or rack.
One rack unit (1U) is 1.75 inches of usable space and is usually, but not always, measured vertically. So, for example, a rackmount device that’s 2U high takes up 3.5 inches of rack space. A rack that’s 20U high has 35 inches of usable space.
Choosing the right cabinet.
Here’s a quick checklist of features to keep in mind before you choose a cabinet for servers or other network devices:
• High-volume airflow.
• Adjustable rails.
• Rails with M6 square holes.
• Moisture and dust resistance.
• Air filters.
• Front and/or rear accessibility.
• Locking doors.
• Left- or right-hinging doors.
• Power strips and cable organizers.
• Interior lighting.
• Availability of optional shelves, fans, and casters.
• Cable management rails, space, and knockouts.
• Extra depth to accommodate newer, deeper servers.
Don’t forget to accessorize.
Even if your cabinet is in a climate-controlled room, you may need to add a fan panel to help keep your equipment from overheating. It’s especially important to have ventilation in an enclosed cabinet.
Rackmount power strips mount either vertically or horizontally. Some have widely spaced outlets to accommodate transformer blocks. Some power strips include surge protection.
Mission-critical equipment should be connected to an uninterruptible power supply (UPS). A UPS keeps your equipment from crashing during a brief blackout or brownout and provides you with enough time to shut down everything properly in a more extended power outage.
For accessories that make cabling easier, just take a look at our many cable management products. We have cable management guides, rackmount raceways, horizontal and vertical organizers, cable managers, cable hangers, and much more. collapse
Black Box Explains...Dry Contacts
A dry contact, also called a volt-free contact, is a relay contact that does not supply voltage. The relay energizes or de-energizes when a change to its input has occurred.... more/see it nowIn other words, a dry contact simply detects whether or not an input switch is open or closed.
The dry contacts in the ServSensor Contact provide a simple two-wire interface that can be easily adapted to third-party sensors and devices. Because you define what the open or closed condition means, dry contacts are infinitely adaptable.
Use dry contacts to monitor alarms such as fire alarms, burglar alarms, and alarms on power systems such as UPSs. A very common use for dry contacts is to detect whether a cabinet door is open or closed.
Black Box Explains...Cabinet accessories.
Once you’ve chosen your cabinet, whether it be a customized Elite or an energy-saving ClimateCab, it’s time to
add accessories for even more function.
Cabinets have two sets of rails,... more/see it nowfront and back, where you can mount shelves, trays, cable managers, and power strips.
Shelves are an easy solution for storing things that aren’t rackmountable. The shelves attach to the rails; servers or other equipment sits on the shelves. Make sure the shelf has the weight capacity you need—some can hold hundreds of pounds. For easy access to components in your cabinet, choose a sliding shelf. There are also vented shelves that improve air circulation within the cabinet.
Although most shelves fit 19" rails, there are shelves that go on the less-common 23" rails. There are also brackets that can adapt many devices intended for 19" mounting to 23" rails.
Keyboard trays are space-saving solutions that also keep your data center organized. They slide neatly into your cabinet or rack—and out of your way—when not in use. And they usually fit into only 1U of rack space.
Further reduce clutter in your server room by using KVM trays that are 1- or 2U high mounted in your cabinet. Special features of Black Box® KVM trays include rock-solid construction, LEDs on the front panel for easy location in a darkened data center, and integrated KVM switching.
Front-panel controls enable you to use the buttons on a monitor bezel without pulling out the keyboard. Some trays have USB ports for access.
Cabinets usually have built-in troughs for cable routing, knockouts for cable pass-throughs, and tie-off points for cable management. You can also add horizontal or vertical cable managers to the cabinet’s rails to manage and route cables more efficiently. Cable managers control bend radius to protect cables from hidden crushes, kinks, and snags, and reduce maintenance time by keeping your cabinet neat and organized. Plus, properly managed cables help to improve airflow.
If you’ve got no room to spare in your cabinet, think SpaceGAIN. You might not think of a patch panel as an “accessory,” but SpaceGAIN angled-port and angled patch panels are not your average panels. They free up valuable space and eliminate the need for horizontal cable managers. You save time and money by routing cables directly into ports. And SpaceGAIN high-density feed-through patch panels enable you to fit 48 ports into only 1U of rack space, with no punchdowns needed.
To save even more space, use SpaceGAIN 90° Right-Angle CAT5e/CAT6 cables. Their up, down, left, or right angles save up to 4" of space in crowded cabinets.
PDUs and UPSs
Control the distribution of power in your cabinet with a power distribution unit (PDU). A PDU can be basic or “intelligent,” with surge protection, remote management, or power and environmental monitoring. Integrate a PDU directly into an uninterruptible power supply (UPS) for extra reliability.
Fans and blowers
Ventilation in your cabinets is critical for keeping vital equipment cool.
An enclosure blower draws cool air from a raised floor at the bottom of the cabinet and delivers it right across
the front of servers or other network components. It fits on standard 19" rails and uses only 2U of mounting space. This high level of ventilation lowers the temperature of cabinet hot spots by up to 15° F. Lowering temperatures protects your electronics against failure caused by overheating, which may enable you to install more equipment.
Fan panels or fan trays direct maximum airflow with very little noise to heat-sensitive rackmounted equipment. Position them in your cabinet wherever you need them the most.
Most network devices take in air through their front panels and expel it out the back. Filler panels in unused rack spaces help keep cool air in the front of the cabinet where it can be used by the equipment.
Most cabinets come with a lock and key, but more advanced options are available to provide a higher level of security. Keyless options include combination locks and biometric locks that read fingerprints. collapse
Black Box Explains...The fully accessorized rack.
After you choose your rack, consider how youll set it up and what accessories you might need.
Your rack may need to be secured. A typical rack has about a... more/see it now15"-deep base, providing some stability, but not enough to prevent the rack from tipping if heavy objects are mounted on it. To solve this problem, most rack bases can be bolted to the floor.
You also need to decide how to accommodate standalone equipment, which is not actually rackmounted or bolted to the rack. You can place small devices on a cantilevered shelf such as the RM001, however, you should place heavier items such as monitors on a center-weight shelf such as the RM377.
Small extras, such as Patch Panel Hinge Kits, can make your job easier. These hinges enable you to access the back of a patch panel simply by swinging it out from the rack. Theyre particularly useful for racks in hard-to-reach areas.
If you need to mount both 19" and 23" equipment in the same rack, use a 23" rack with 23"-to-19" Rackmount Adapters to fit the 19" devices.
For a neater appearance, you can cover unused spaces in a rack with Filler Panels.
Cable management is also an important consideration. Our Horizontal and Vertical Cable Managers help you to route cables along the sides of racks, between racks, and to the rackmounted equipment. collapse
Black Box Explains…Remote monitoring.
Beyond virus protection.
It has become almost automatic to protect your data center by backing up your servers, installing firewalls and virus protection, and keeping the protection up-to-date.
But what about... more/see it nowmore tangible threats? Do you have hot spots in your racks? If the cooling system shuts down, how will you know when temperatures climb out of control? Are you
alerted to humidity changes or water leaks
that threaten your equipment?
Planning for the unexpected is a critical task because there are more systems performing mission-critical functions than ever before. These systems are often deployed without the proper environmental infrastructure to support them. Equipment density is increasing constantly, which is creating more stress on ventilation and power.
The top three IT risks:
1. Environmental disruption.
The number one cause of downtime for remote locations, environmental problems go beyond fires and floods and affect as much as 30% of a company’s mission-critical infrastructure. Cooling and power are key points of exposure and increase as equipment density does.
2. Unnecessary risk.
When systems are housed in less-than-optimal settings, or are in remote and unsupervised locations, any error causes downtime. Yet, it’s not practical to have someone babysitting the servers.
Regardless of the probability, terrorism is
now something each of us must plan for. Your systems can also be brought down from within if the proper security safeguards are not in place.
What’s an environmental
Environmental monitoring products enable you to actively monitor the conditions in your rack, server room, data center, or anywhere else you need to protect critical assets. Conditions
monitored include extreme temperatures, humidity, power spikes and surges, water leaks, smoke,
and chemical materials. With proper environmental monitoring, you’re alerted to any conditions that could have an adverse effect on your mission-critical equipment. These products can also
alert you to potential damage from human error, hacking, or prying fingers.
Environmental monitors consist of three main elements: a base unit, probes or sensors, and
network connectivity and integration. The base units may contain one or more built-in sensors,
as well as ports for hooking up external probes. Additionally, they include an Ethernet port and have software for remote configuration and graphing. This software may also work with
existing network management software,
such as SNMP systems.
An environmental monitoring appliance
displays the values measured by the attached probes, e.g. temperature, humidity, airflow,
status of dry contact, door, motion detector,
and other sensors.
Data collecting and graphing.
Measurements are periodically stored in the internal memory or external storage media and displayed as graphs.
When the measured value exceeds the
predefined threshold, it triggers an alert: a blinking LED on the front panel, an audible alarm, SNMP trap, e-mail, etc. The environmental monitoring appliance can also activate an external alarm
system like a siren or strobe light.
Benefits of environmental monitoring:
Reduced downtime—When things go wrong, you’re the first to know. Minimize downtime by being alerted about conditions that cause damage to servers and other network devices.
Increased profits—Environmental monitoring systems are easy to implement. Also, they help you cut replacement equipment costs and redistribute your workforce more effectively.
Increased employee satisfaction—With built-in notification features like e-mail, SMS, and SNMP traps, a remote monitoring system enables employees to better manage their work.
Envornmental and security monitoring systems can be used for a variety of applications, including:
Data center monitoring
Computer room monitoring
Rackmount industrial equipment
Food and beverage applications
Air conditioner/refrigerants/freezer monitoring
Black Box Explains...Fiber connectors.
• The ST® connector, which uses a bayonet locking system, is the most common connector.
• The SC connector features a molded body and a push- pull locking system.
• The FDDI... more/see it nowconnector comes with a 2.5-mm free-floating ferrule and a fixed shroud to minimize light loss.
• The MT-RJ connector, a small-form RJ-style connector, features a molded body and uses cleave-and-leave splicing.
• The LC connector, a small-form factor connector, features a ceramic ferrule and looks like a mini SC connector.
• The VF-45™connector is another small-form factor connector. It uses a unique V-groove design.
• The FC connector is a threaded body connector. Secure it by screwing the connector body to the mating threads. Used in high-vibration environments.
• The MTO/MTP connector is a fiber connector that uses high-fiber-count ribbon cable. Its used in high-density fiber applications.
• The MU connector resembles the larger SC connector. It uses a simple push-pull latching connection and is well suited for high-density applications.
Find the right screw length for your cabinet or rack.
Types of Screws
There are two basic kinds of screws used for cabinets and racks—panhead screws and countersunk screws—and... more/see it nowthey’re measured in two different ways. Because the standard way to measure is from the tip of the business end of the screw to where the screw rests on the material it’s fastened to, a panhead screw is measured to the bottom of its head, whereas a countersunk screw is measured to the top of its head.
Black Box Explains...Cable management.
Corporate networks are complex systems of PCs, servers, printers, and the devices that connect them. Getting everything to work in harmony requires bundles of cables, and managing all those cables... more/see it nowfrom inside a telecommunications closet can be a daunting task. To connect cable bundles to rackmounted equipment (like patch panels, hubs, switches, or routers), you need to direct the bundles overhead, vertically, and horizontally.
A popular choice for overhead cable routing is a ladder rack. Ladder racks come in many varieties. They can run along a wall supported by brackets or they can be installed overhead and supported by a threaded rod. Ladder racks can support large cable bundles neatly and safely. Because bundles lie flat on a ladder rack, cables aren’t subjected to harsh bends. You can run ladder racks directly to the top of most standard telecommunications racks that conform to TIA/EIA standards.
Use vertical cable managers to route cable bundles along the sides of a rack. These “cable troughs” as they’re sometimes called can be single sided—or double sided to route cable bundles to the rear of equipment and to the ports on the front as well. Vertical cable managers usually come with some type of protection for the cable, such as grommeted holes to protect the cable jacket or a cover that may clip on or act as a door.
Horizontal cable managers are usually a series of rings that directs cables in an orderly fashion toward the ports of hubs, switches, and patch panels. collapse
Mounting flat-screen displays.
Traditionally, computer monitors, TVs, or other video displays have simply been placed on a shelf or desktop. However, today’s flat screens are less stable than older vacuum-tube displays and should... more/see it nowbe secured to prevent tipping. Fortunately, most new displays meet the VESA standard, meaning they have a hole pattern on the back that fits any VESA standard mounting device such as a wall mount, desktop mount, or ceiling mount. This enables you to secure the display to prevent damage from accidental jolts and bumps. Additionally, a mounted display is less likely to be the object of theft. collapse
Black Box Explains...Remote access.
Remote access is the ability to access a network, a personal computer, a server, or other device from a distance for the purpose of controlling it or to access data.... more/see it nowToday, remote access is usually accomplished over the Internet, although a local IP network, telephone lines, cellular service, or leased lines may also be used. With today’s ubiquitous Internet availability, remote access is increasingly popular and often results in significant cost savings by enabling greater network access and reducing travel to remote sites.
Remote access is a very general term that covers a wide range of applications from telecommuting to resetting a distant server. Here are just a few of the applications that fall under the remote access umbrella:
Remote network access
A common use for remote access is to provide corporate network access to employees who work at home or are in sales or other traveling positions. This kind of remote access typically uses IPsec VPN tunnels to authenticate and secure connections.
Remote desktop access
Remote desktop access enables users to access a computer remotely from another computer and take control of it as if it were local. This kind of remote control requires that special software—which is included with most operating systems—be installed and enabled. It’s often used by those who travel frequently to access their “home” computer, and by network administrators for remote server access. This remote access method has some inherent security concerns and is usually incompatible with firewalls, so it’s important to be aware of its limitations and use adequate security precautions.
Remote KVM access
A common application in organizations that maintain servers across multiple sites is server administration through an IP-enabled KVM switch. These IP-addressable switches support one or more servers and have an integral Web server, enabling users to access them over the Internet through a Web browser. Because they’re intended for Internet use, these switches offer authentication and encryption for secure connections.
Remote power management
Anyone who’s ever had to get out of bed in the middle of the night to go switch a server off and back on again to reset it can appreciate the convenience of remote power management. Remote power managers have a wide range of capabilities ranging from simple power switching to reboot a device to sophisticated power monitoring, reporting, and management functions.
Remote environmental security monitoring
Remote environmental and security monitoring over the Internet is increasingly popular, largely because of the cost savings of using existing network infrastructure rather than a proprietary security system. This application requires IP-addressable hubs that support a variety of sensors ranging from temperature and humidity to power monitors. Some models even support surveillance cameras.