RU is the unit of measurement to describe the size of the device which is to be deployed inside the datacentre. One RU equals to 1.75 inches in height with 19 inch or 23 inch in width. The 19-inch rack is a standard size of enclosures for mounting most of the equipment.
kilo Watt hour- kWh
Electric Power to the datacentre is supplied in kWh units. 1 kWh is the amount of energy supplied in one hour at 1000 watts power level.
Intrusion Detection System- IDS
An IDS is a hardware device or a software which monitors and ensures that there are no malicious intrusions in the datacentre’s network. On detection of any violation of the network security such as an unauthorized access to the system, an alert signal is sent to the datacentre management.
Power Distribution Unit- PDU
PDUs are power distribution units installed within the datacentre that are responsible for supplying power to the equipment in datacentre.
Uninterruptible Power Systems- UPS
These are the backup units (batteries, generators) installed within the datacentre. On disruption of main electric power supply due to any reason, the backups are used. The main purpose of installing UPS is to run datacentre with zero downtime. The capacity size of UPS varies depending upon the power requirement of the datacentre.
Service Level Agreement- SLA
SLA is a service contract between the companies and ISP (internet service provider). The company’s objectives, availability and requirements are mentioned in this contract. It includes the value of mean time between failures (MTBF) and mean time to repair (MTTR). This agreement makes it the service provider’s responsibility to ensure guaranteed availability of services.
Estimated Time of Repair- ETR
ETR is the total time required to recover from a planned or unplanned outage in a datacentre. In case of natural disasters such as fire or flood, the ETR value would be infinite. The ETR value is included in the SLA.
Power Usage Effectiveness-PUE
This key term is widely used in a datacentre. PUE stands for Power Usage Effectiveness. It shows that how effectively a datacentre uses its electric power.
PUE = Total power used by equipment / Total power delivered
An ideal value of PUE is 1.0.
Datacentre Infrastructure Efficiency- DCiE
DCiE it is the performance measure which represent the energy efficiency of the datacentre. It is the inverse of PUE. A DCiE value of 60% means that only 60% of the total electric power is consumed by IT equipment and the remaining 40% is supplied to cooling and ventilation.
Datacentre Infrastructure Management- DCIM
The integration of IT and facility management is called datacentre infrastructure management (DCIM). This integration is done for centralize monitoring, capacity planning and management of datacentres. This makes it easier for IT project managers to eliminate any source which can cause risk to datacentre availability and identify the interdependence between the IT system and the facility.
Heating, Ventilation and Air-conditioning- HVAC
HVAC refers to heating, ventilation and air-conditioning system. It is installed for the indoor and environmental comfort of the datacentres. This technology is used in data centres as it houses a huge number of computers generating a lot of heat and humidity.
Computer-room Air-conditioning- CRAC
These units are used to monitor temperature, humidity and air flow inside the datacentre. These are very critical components of the datacentre as they monitor and maintain the temperature. These units are now replacing air-conditioning units that were used in past.