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A Tidy, Maintainable Cabinet Wiring Methodology?
mawhin asks: "I've seen a couple of articles highlighting readers' favourite tidy/untidy cabling, and conversations along the lines of 'I always do my cabling *real* tidy' / 'yeah but how can you change stuff when everything is zip tied down'. 'Use velcro not zip ties' is obviously a good tip, but what I'd really like to know is how you all do it. My particular situation involves multiple racks of switches next to racks of patch panels. What methodology would you recommend for installation and ongoing change to ensure that stuff is tidy enough to be able to trace cable; isn't so tight the you can't re-patch without stripping big chunks of cabling out; and the arrangement doesn't inevitably deteriorate?"
...spark plug wire spreaders from the hot rod ricer store. Well you asked! I'm an old gear head, that's what I would use! They look sharp!
Where I used to work, they would stack their MDF (Main Distribution Frame) full of patch panels, 4U each and 11 per frame. Each panel would host 144 ports. Front and back came to over 3000 pairs of fibre coming into each frame. This was done without any horizontal cable management. Well-spaced cable management, both horizontal and vertical, is key to a maintainable bulk cabling system. We finally migrated all of that to new MDF, with 2U cable management between every two patch panels and dropped the port density per panel from 144 to 72. That made 2U of cable management for every 8U of patch panel space. This made it very easy to trace and pull fibre without unintentionally impacting other fibre paths. With good cable management products in a well-thought out arrangement, you may not even have to use ties. Even in your switch cabinets. All of this fibre ran to several fully-populated McData FC switches, and we would put cable management both above and below each switch. This would allow us to run the cable in, through the management, and either straight down or straight up to the appropriate switch port. We didn't even need ties.
What?
There are ways to keep wiring racks tidy but few do it.
Some hints:
Whether a wiring job eventually deteriorates or not is up to you, not the setup you've chosen. If you have the kind of personality and drive to keep it clean, you will, no matter what setup you use.
There is no magic bullet arrangement of cables and velcro that is immune to entropy.
Ever notice that most switches group their ports in 4 or 6 to a group? What I do in these cases is bundle my patch cables in that same number between the panel and switch. makes it much easier to trace one when you can locate the small bundle, then isolate the specific cable. I usually just used the same twist ties that the patch cables came packaged in, but you could also use velcro. I was just being frugal. In most cases, I tied the bundles together in at least 3 points along the length of the bundle, assuming they're all going to the same panel and switch. Kept the bundles neat. I typically routed the small bundles using cable management panels on the racks that came equipped for it (all of them, after I started specifying).
It's not photo-pretty, but it is practical, very easy to modify at need. Some of those photo racks I'd be afraid to mess with for fear of having to try to return it to that state!
Little girls, like butterflies, need no excuse. -- L. Long
I'm in the server room, grooming cables, all the time.
I do this because the other people I work with will string a cable across the room at neck height or ankle height. They don't care. Their tolerance for sloppiness is far higher than mine.
Even though they are happier when they have to trace a problem just after I've finished cleaning up. They're not willing to put in the effort to keep it clean. And there's really no way you can make someone be neat (without firing him).
Quality appearance is a bit more expensive. Realize this and accept it.
Buy the patch cables that are serialized at each end.
Buy THE CORRECT LENGTH patch cables.
Use Velcro, never zip ties.
Always leave room for expansion.
Color code. We use green exclusively for telecom (TDM, and VOIP), Blue for standard jacks, etc. NEVER violate color coding, even though it is incredibly tempting to do so.
As an addition to what other folks have said, keeping your rack neat takes work.
In my data center, temporary cables are bright red (other network functions are also color-coded), and the policy is that each temporary cable has a service tag (little paper-and-string one) on it with the initials of the person who installed it, the date they installed it, the date they expect to remove it, and the number of the bugzilla bug that's associated with it.
Related policy is that any non-red, non-bundled cable gets removed immediately by anyone who sees it, as do any red cables without a service tag.
When I started this policy, there was a lot of unhappiness about it (and the racks were an unholy mess), but after about a year or so, I've noticed that our wiring guys no longer need to spend a day or two a month rerunning wiring in some rack (with an associated service outage). Three years later, the data center has doubled in size, my headcount for management has stayed the same, and everyone is (usually...) working 8-hour days.
Oh, and the other hard bit about keeping racks neat: If you're managing people who don't share your desire for neatness and documentation, get used to being called all sorts of nasty things behind your back when you start putting "neat rack" policies in place.
Do you mean like these?
Or if you are in a situation where there are already un-labelled cables, use one of these. It's a tone generator and probe. Plug the generator in at your drop, and use the probe to find that cable on your panel. We have one of these that we paid $180 for, but the one on the link is cheaper. We also got a cable tester that also generates tones, so you can put the generator/tester at the drop, go to the panel, locate the cable with the probe, then plug in a receiver from the tester kit and it will tell you the status of the cable. It's just a tester, not a cable certifier. Those are crazy-expensive, and not necessary for my work.
(no affiliation with triangle cables, just the first link I googled)
-- Having a Creationist Museum is like having an Atheist place of worship
Found this a while back:- 1.html
From a Network Wiring Mess to Wiring Nirvana
http://techrepublic.com.com/2300-10879_11-5896894