Wednesday, January 7, 2009
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How to Choose a Data CenterBy: More articles by Michael Lemm
When evaluating a data center to support your business much of your focus is on bandwidth, reliability, QoS, and so forth. But there's much more to consider in order to make a smart decision. Over look it...and you're liable to make a big mistake.
The Building Security....
You want to see a building that has quality security systems and staff. I want to see some form of man trap with some type of biometric or scanned ID card system at any entrance to the building. This prevents just anyone from walking in any door. After the man traps I want to see a 24/7 security guard and some type of video camera system. In the better facilities, when you get on the elevator you have to do another swipe of your card again just to get to your floor. This is good security, it stops someone who is not authorized to be on your floor or area from getting off where they have no business. Once you are on your floor you should look to see if it has video cameras that cover the entire floor. You may need to have your card scanned once more or have another form of checked access. After that you want to make sure your racks or caged area has a secure lock. In one of our data centers you have to go through 6 security scans of one kind or another plus a guard an then a lock on the cage space and the cabinets to get to your servers. You will be also covered by cameras from the second you enter the building to the time you leave. Is this to much? No not at all. When you are dealing with either customer data or customer equipment you must show that you are providing the best possible security. One of our largest clients is a medical facility. We were told we got the contract to host 30 servers for them because we had the best physical security. I don’t care what data center you are in they should have a minimum of 2 security/ID scans, 24 hour video and at least one 24/7 security person, A tech is not a security person.
Power System....
Initial Power: In the ideal situation the data center should be connected to 2 city power grids with multiple entry points from each grid to the building. This usually only happens in major cities in downtown districts where there is the normal power distributed to the area plus an additional power grid that is meant to support emergency services such as government or medical facilities. Even if the data center is only on a single power grid, which is most common, you want to make sure it has multiple entry points for power. I’ve seen several data centers that if a truck ran in to the wrong pole, or a fire started or a construction accident occurred in the underground pipes, the entire datacenter would be without power for a number of days because it was only routed one way.
The power distribution panel(s) need to be clearly marked and ID’d. Ideally the data centers network equipment will be separate from the client’s equipment. Each rack should have 1 or 2 breakers that are exclusive to that rack. General electrical outlets or public outlets should not be on the same distribution panels as networks or servers.
Automatic Transfer Switch (ATS)....
The transfer switch senses when utility power is interrupted, and starts up the generator if the utility power remains absent. In about five to ten seconds, when the generator is producing full power, the transfer switch disconnects the load from the utility and connects it to the generator, restoring electricity to the load. The transfer switch continues to monitor utility power, and when it is restored, switches the load from the generator back to the utility. Once the generator is disconnected, it goes through a cool-down routine and is automatically shut down.
Transfer switch types include open transition, momentary closed transition, and bypass isolation
Open transition transfer switches are the simplest kind, and are mechanically interlocked. They disconnect the load from one power source before making the connection to the other.
Closed transition transfer switches (CTTS) eliminate momentary power interruption when both sources are present and synchronized, by transferring the loads with an overlapping contact arrangement. The momentary closed transition switch transfers the power within one hundred milliseconds, which does not require utility protective relaying.
The soft load closed transition switch extends the overlap time to multiple seconds, for a smoother transition of load to the generator. These switches are available in 100 to 2600 amp configurations.
The better brands are Caterpillar, ASCO, MGE and Hubble
Generators....
If a datacenter doesn’t have its own generators and fuel storage don’t host there. It’s that simple. The generator should be able to handle at least 125% of the load for a minimum of 24 hours without being refueled. A really great data center will have multiple generators. One of our data centers has an individual generator for each floor and two backups. The building can route power from any generator to any location in the building and they can transfer fuel from any generator to another.
One thing you want to do and see for yourself is that they test the generator system. I’m not talking about just starting it on but that they actually put part of the data center load on the generator. I’ve asked about a dozen of the data centers we’ve looked at to allow me to be there when they did their “weekly” test of the system. It was funny how they hemmed and hawed and came up with excuses why I couldn’t be there to see the system tested. If they won’t let you watch them go through their testing it should tell you they are probably not doing more than just starting the generator and hoping the rest works in an emergency. That’s just not good enough to tell you if the generator system is really working or not.
PDU/UPS....
Every cabinet should have its own PDU. It should run a minimum of 10 minutes with a full load. It can often take generators or other systems a full 10 minutes to come on line. Ask to see the batteries of the PDU. The terminals or poles should be clean and without any corrosion or other stuff on them. Most batteries these days have dates stamped on them. Make sure they are no older than 2 years old. Ask the data center how often the replace or update their battery farm. PDUs should also provide on-line power conditioning, with a wide input supply range that reduces battery over-usage, surge protection, EMI/RFI filtering, and harmonics attenuation The better brands are Liebert, MGE and Powerlink.
Power Monitoring....
A good data center has some form of dedicated power monitoring system. The system should monitor the status of an SNMP-equipped UPS system over a standard Ethernet network. Additionally, the software should be programmed to automatically shut down network loads upon power failure, and even send alerts to notify personnel of power problems. It should also be possible to remotely control specific UPS output receptacles on single-phase UPS systems. The better systems will provide audio alerts, emails and SMS messaging
Remember to include the above factors in your data center evaluation checklist...and you're more likely to make a choice that makes good business sense.
About The Author:
Michael is the owner of FreedomFire
Communications....including Business-VoIP-Solution and
DS3-Bandwidth.com. Michael also authors Broadband Nation where you're always welcome to drop in and catch up on the latest BroadBand news, tips, and insights.