Data centre 101

Summary:Secrecy seems to shroud the data centre arena -- all well and good for security's sake, but not so great when trying to pick a provider. RMIT IT Test Labs' Kire Terzievski pulls back the curtains to find what data centre options exist.

Building management
Managed services
Second data centre
Data centre checklist
Sidebar: HP develops smart rack
About RMIT


Cabling pathways in a data centre are found in overhead cable trays and under raised floors. The raised floors hide cables quite well and provide easy access. They are mainly run in separate pathways from power cables and fire suppression systems. This applies to both standard Cat 5 cables and fibre cables which are also run in separate pathways or ducts, mainly because they have different stress requirements to plain copper.

Data centres will usually guarantee you a minimum level of bandwidth, while at the same time allowing you to take advantage of spare bandwidth so you can burst up to a maximum level. Customers have the chance to choose from a number of bandwidth plans which include monthly metered bandwidth and then excess bandwidth charged per MB. These plans are suitable for customers that don't expect to get too much traffic.

Customers can also purchase burstable plans which may vary in speed. These plans would be used by customers who expect heavy traffic.

Another focal point of a data centre is the internal network.

Networks in data centres contain routers and switches that transfer data from your servers to the outside world. Not being able to communicate with the outside world would spell disaster for your company, so you will find data centres will offer fully redundant networks so there is no single point of failure.

Service levels
Data centres provide customers with service level agreements measured on a monthly basis, 24 hours a day, seven days a week.

Most of the time you will see data centres advertising 99.9 percent uptime, or with few more nines after the decimal point. This information is usually found on data centre Web sites. Scheduled maintenance or outages caused by other carriers are not considered to be part of the normal downtime.

Accessing your equipment
Efforts to conserve space within a data centre KVM (keyboard, video, and mouse) switch are becoming a lot more popular.

These efforts allow a single keyboard, monitor and mouse to control multiple servers. Hardware such as the Command Centre from Raritan, which is new to the market, allows you to remotely monitor all your servers through one box and you only have to remember one IP addres -- that of the Command Centre.

Once connecting to the Command Centre you can view information on ports, users and devices connected to your servers.

The cost of leasing rack space can vary dramatically. It depends on the levels of security that are offered and the bandwidth that is purchased. You also have to take into consideration managed services fees. It's really best to contact the hosting facility so they can work out what's best for you. Data centres will rarely advertise cost, preferring instead to provide this information upon request.

Data centres offer two types of racks -- open racks and locked cabinets. Open racks work out to be a lot cheaper but they are less secure.

With an open rack, your rack is enclosed in a cage with other customer's equipment. The racks aren't individually locked, but are locked in the cage. When you need to access your equipment a security person would typically escort you to your rack.

With locked cabinets you get the flexibility of having your own security key to the cabinet. You can also lease a whole cage if you think you will fill it up as well as secondary redundant cage or a rack at a different site.

Bandwidth is usually charged per MB and for incoming traffic only and depending on whether the data centre has access to multiple Tier 1 connections, you tend to pay more.

Topics: Security, Big Data, Hewlett-Packard, Networking

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