Data Centers optimize

10 cabling tips to keep your data center manageable

With a little planning and a few best practices, you can avoid the problems and maintenance headaches that come with improper cabling.


Cabling tips

Your data center is the heart that pumps the lifeblood of your business. Without it, everything stops. And when it has problems, so does your business. Myriad issues can plague a data center. And although most people don't realize it, improper cabling can be one of those issues. But with some easy planning and work up front, you can maximize the efficiency and reliability of your data center cabling.

I have put together 10 tips to help you get the most out of your data center's cabling. With these tips, you'll have a more reliable data center and your staff will have a much easier time maintaining it.

1: Measure twice, cut once

It's an old adage, but an important one. Not only do you create a tangled mess if you don't carefully measure your cables, you also create a lot of expensive waste. You may think that two feet of wasted cable doesn't amount to much, but those wasted feet add up. In the end, you could save yourself a lot of time, headaches, and money by measuring twice and cutting once.

2: Label, label, label

If you don't label your cables, you're only making more work for yourself. Every cable should have a label on both ends, even short runs and patch cables. Why? Imagine you have to test a bunch of circuits -- quickly. You scramble and unplug a few patch cables and, when it's time to reset them back to their default locations, you have no idea where each cable goes. Avoid this problem by taking a little time to slap a label on each end. Make sure your labeling system is consistent. Don't just go ad hoc with this or you'll confuse yourself and those who work for you.

3: Don't skimp on terminations

Don't buy cheap because they're cheap and don't rush through the process of terminating cables. If you have cables that lose their connection if you wiggle them, you need to redo them. If you can't terminate cables in your sleep, you need to practice. You may think you're saving time and money. But in the end, you're going to wind up with a monstrous headache as you troubleshoot all those terminations.

4: Don't skip the test

After you create a cable, test it! And don't accept "Star Pass" tests (a test that barely passes). If a test doesn't pass 100%, redo that cable. If, after a few tries at termination, the cable still doesn't pass, trash it. And make sure you're using a quality tester for your cables (and that you know precisely how to use it). This simple step can prevent a lot of extra work in the end.

5: Keep patch cables short

You have servers in a rack that are within a foot of each other. Don't slap three-foot patch cables on those servers -- it not only looks bad, it's incredibly inefficient. And if you have an odd length between servers, use your termination (and testing) skills to create patch cables that reach perfectly. With that extra length on your cables, you invite tangles, kinks, and confusion.

6: Color code

This may sound a bit over the top, but stick with a single color for your patch cables and cable runs. The only time you should break that rule is when using a specific color cable for a specific purpose. But don't use colors randomly. Make sure each color has a purpose and stay with it. That will make it easier to follow cable runs and troubleshoot issues. And yes, it also makes for a better-looking data center -- which has its merits.

7: Upsize your conduit

Don't buy conduit sized for what you need NOW. Buy conduit sized for what you will need in the future. You never know when you'll be adding on, and you'll want to be able to make use of already-run conduit. You can't do that if you purchased a size that just barely fits your needs at planning time. Go big or go home.

8: Make your design cable-friendly

When you lay out your data center plans, do so in a cable-friendly way. Don't put a rack in a location where it's impossible to successfully run cable. Otherwise, you'll wind up with cable on the floor or hanging from the ceiling. Plan carefully to avoid later disaster. Also make sure to plan with expansion in mind. Run extra conduit, extra drops -- more than you think you'll need.

9: Separate Cat5 and power lines

Do not run Cat5 and power together. You might think it's too minimal to be of concern, but those power lines can leach signal and cause interference with your Cat5. Yes, bunching a lot of Cat5 together can do the same thing, but not with nearly the ill effect of running them alongside power. Keep power and networking separate at all costs.

10: Keep cables cool

You may think only the servers need to be cool -- but that would be a poor assumption. Cable can get warm as well, and if you have a massive amount of cable, that extra temperature can lead to disaster. Design your data center in such a way as to keep your networking runs cooled, as well as the server racks.

Spaghetti prevention

Cabling is often an afterthought. But when you treat it as such, you are running the risk that you'll find yourself elbow deep in a spaghetti bowl of networking cables, attempting to resolve issues that could have been prevented with just a bit of care up front.

About

Jack Wallen is an award-winning writer for TechRepublic and Linux.com. He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website getjackd.net.

29 comments
bluepromocode
bluepromocode

I very simple but useful tool is a simple pack of multicolored electrical tape. Using this, you can group cables together, and use color coding to keep things differentiated and organized. At our office, I use this and its very effective (and cheap).

 

Edited to remove link

pmshah
pmshah

The biggest and most frequent problem that I have encountered with network cables is the latching tab of the RJ-45 connector breaking off. I have seen spring steel latching tabs on polycarbonate housing in various other applications. I don't see any reason why it can't be incorporated in the present situation. The overall dimensions of the plug and socket can easily allow for this. I can't figure out why not a single manufacturer has come up with a similar idea to replace the current unreliable design. Are the cable and termination manufacturers is such bad shape that they count on repair / replacement market to survive?

cptroger
cptroger

I would like to add anther tip:

If you use tie-reps to keep your cables together, use a cable cutter for the tie-reps that make a clean cut, so you won't scratch or cut yourself on the cut-off tie-rep in the future.

hazmoid43
hazmoid43

One of the worst was a Government department I worked for,  When they pulled out their DEC machines and replaced them with windows servers, the IT tech spent the weekend ripping up the suspended floor and removing cables that were no longer required.  As I hear it he took 2 ute-loads of cable to be recycled :)

Also you do need to label your cables, seriously look at investing in a Rhino labeller.  This creates a wrap around sleeve and label in one.  much neater and easier to read.  Used the Krone Highband  cabling at my last work and this was great for being self documenting.   

patof
patof

about #5, way back when I heard that cat 5 minimum length should not be less than 1 meter because of the wavelength issue or something similar...   so wouldn't a one foot cable give problem?

phil hayes
phil hayes

The other one I would add is "photograph everything" and do it regularly. Digital images take little space and are a great point in time record of how things are. If you do it properly they can also identify the equipment and even the labels and serial numbers. It is hard to argue with a photograph.

Many years ago while working for another company I reviewed a computer room and found an instance of the worst cabling practice I have ever seen. A production switch was hanging from the top and back of a rack held in place by a single piece of blue packing tape.

When I advised the IT GM he almost took my head off saying I did not know what I was talking about. The photograph resolved it issue quickly.  

aprecht
aprecht

I may have to (slightly) disagree with you on labeling cables. I say slightly, because there is a better way. I have found labels on cables to fade, fall off, impede air flow, look nonprofessional, are a rats nest...

I find it far better to fill out an appropriate description in the switches description field for every port. e.g. Server1 eth0.

In the server OS I would use something like Name=”vlan123 port 1/0/1” For me this has the added benefit of showing up in Nagios. Making the data path obvious from my trusted cubicle chair.

DetonateTheBomb
DetonateTheBomb

Another obvious tip would be to have qualified network infrastructure technician....such as me who cant find work in s.a.. But yes.. i mostly agree with RMS... a healthy cabinet or data center, would be well vented, cooled and constant maintenance updates. A cable tech is no such thing if he cant follow  ISO 11801 standard. I sleep in a clean house, i work in a clean an tidy work environment. Don't want to choke on spaghetti.

RMSx32767
RMSx32767

11. If a cable is no longer in use, remove it or label it (include the date) as such so folks aren't wondering "why is this cable not plugged in?"


12. Even if it's a short-term need, don't run the cable along (or above) the floor; lift the panels and run it under them.


jasongon
jasongon

On the management side I would add Intelligent Infrastructure Management Systems as an excellent option. On the other hand, Cat 5e is already out of the Data Center standard (TIA-942-A) and only Cat 6 or 6a are accepted.

Leonard Igunbor
Leonard Igunbor

How do you go about managing such mess without bring everything down?

Sanders Kaufman Jr.
Sanders Kaufman Jr.

Never disconnect anything unless you need to please some anal-retentive inspector. Just hire a minimum wage temp to tag each end of each cable with a sticker... and don't repeat the mistake of letting it get that way in the first place ever again.

Stijn Kuppens
Stijn Kuppens

an inventory of all the patches and links would be the first thing... then the use of colorschedules, cablemanagementunits. You don't have to bring everything down.... it will be a pain in the @ to re-arrange this mess ;-)

Vick Damone
Vick Damone

I good tech with the knowledge of understanding that professional work in expected at the work place. Oh yeah and proper cable management.

Shawn Quinn
Shawn Quinn

I just finished working as the site admin for a company whose IT room looked exactly like this. And the thing is , how do you fix it without bringing everything down for a day?

Mathew O'Hare
Mathew O'Hare

I expect this to have a cat or dog in the middle saying the moth was caught.

Matt Kearns
Matt Kearns

I read a whitepaper that advocated the use of overhead racks instead of under-floor wiring mainly because of the heat issue.

tim.lovegrove
tim.lovegrove

I would extend points 7 & 8 to include spec'ing and running more cables at a time. The cost of having new cables run is mainly in getting an electrician onsite, and running 10 cables to an area is hardly any more expensive than running 2. If you're planning a job that needs a bunch of cables running, it's always worth assessing what other cables you could run at the same time to get the best value for money.

mjd420nova
mjd420nova

I try to keep the cable bundles as large as possible during installation.  If node or server ID helps, keeps groups together that way.  Larger groups may be by floor or even building with sections.  The easier to identify a group and then an individual cable may pay dividends later.  Seperation  from power conduits and other equipment,( suppressors, UPS, breaker panels) is essential especially under floor plates where  magnetic waves can get trapped. 

cptroger
cptroger

@patof there is no minimum requirement, shorter the better actually (signal strength wise).

cptroger
cptroger

@aprecht Kinda depends on the quality of the label. I got Rhino "pro" labels at home, but at work we use Brother, and to be honest the guality is much highter.