MOVE IT! 10 top tips for shifting your data centre The scenario's a hauntingly familiar one. You're the IT person who's just been told by the boss: “We're moving the kit to <insert name of whatever data centre he's signed up with in a panic>, now get on and do it.” I've done more than my fair share of migrations from on-premise systems to data centres – and more often than not …
A few years ago the UK based company I used to host my website and email moved from the centre of London to somewhere less expensive. They said the move would take 48 hours maximum (over the weekend). After one week my site and email were still down and their phone numbers dead and no response to emails. Their status web page was also still down (presumably hosted from their own in-limbo data centre). After two weeks I took my service needs elsewhere. A few months later they contacted me to renew my contract... not no way, no how, no chance! How NOT to shift your data centre.
Seriously useful for peering into hard to reach nooks and crannies. Especially in datacentres where tidy cabling isn't all that high on the priority list - i.e. everywhere.
And don't forget your torch either. Some of those places are darker than the offices in CSI.
Also: A magnet on a gooseneck, plus a claw on a goosneck. Theyr'e seriously useful bits of garage mechanic kit that save a lot of faffing around when you drop a screw into inaccessable spots.
As far heavy kit such as goes: USE A LIFTER. The cost of one in a data centre vs the cost of claims if someone gets hurt make this a no-brainer (usually this is only thought about AFTER someone gets hurt and lodges an expensive claim) and the stability of the things makes installations a trivial one-person job.
Tawi and Serverlift are 2 vendors. A decent colo centre should have such devices on the floor.
"Some bits are obvious: cable ties "
You missed the words NO FSCKING before cable ties. Anyone using cable ties near me in a data centre will lose their fingers PDQ to stop them committing such a sin again. It's velcro or untidy cables for me, I've seen too many snapped fibres, cut cables and impossible to rewire situations over the years and every experienced techie I know feels the same.
Can't say I agree other than on fibre - using cables ties on fibre is a shooting offence. However, IME, using Velcro or anything like that (or no cable ties) invites people to start rearranging things themselves. Any issues I've seen with cable ties comes with idiots using knives or side cutters to remove them when they should be using flush cutters.
I'd also a cage nut insertion tool to the list of necessaries - I've lost more than enough flesh over the years.
Yeah, I'd rather make any changes myself and know it's done right than have them be able to change themselves. Assuming it's designed and implemented properly (or the customer doesn't suffer from Creeping Requirements disease, for which I'd cheerfully put them down) then changes should be minimal.
"Any issues I've seen with cable ties comes with idiots using knives "
MOST issues I've seen with cable ties come down to twats pulling them far too tight and screwing up the geometry of the network cable, thus wrecking its impedance. This is hypercritical at 10Gb/s
Velcro has the significant advantage that it's virtually impossible to overtighten. (not to mention no sharp edges when you've got your hands in the back of a cabinet).
"I'd also a cage nut insertion tool to the list of necessaries"
Seconded, but not the clamp ones - the simple "economy" stainless-steel loop works far better as they are attacked from the front (I find them 5-10 times faster than the clamps)
http://www.pgcomputercomponents.co.uk/economy-cage-nut-insertion-and-removal-tool-635-p.asp
The biggest problem with these ones is idiots who don't know what they're for and throw them out.
Definitely, the cheapie ones are perfect for the job and I always inherit them after a job, cos as you say no one know what they are for. Until you demonstrate and everyone wants one. ;-)
It's personal preference as they aren't cheap (or at least, good ones aren't), but I like to use a cable tie gun to tension and cut the ties for a neater job and to avoid over tensioning.
Nah, I'll hang on to both thanks. Velcro strips are perfect for cabling that may be changed from time to time. But where I have stuff that I plan to leave untouched for a long time (the Internet or WAN connection going into the edge router, for example, or the fibres connecting the uplink of my switch stack to some other part of the infrastructure) I prefer to clip it in snugly with cable ties so it can't be inadvertently pulled out by someone mistaking it for a more transient connection.
And if your not in someone elses DC but your own and you move to your own new one, dont forget to order enough air handler capacity for the extra racks installed during upgrade, check the floor is capable of supporting the extra battery weight needed by the ups, and actually has a big enough connection to the substation to power it all on at once. Oh and that your new shiny servers actually fit in your new standard rack size and dont need ones the length of mars so you have to buy the vendors racks to fit them in.
I liked working in the sharp end, troubleshooting someone elses cockups on the fly and saving the day it has to be said, as it gives you that rare thing in IT, a actual sense of worth and that you made or saved the company considerably more than you cost, I still do that or they would be rid tomorrow but it doesnt show as much of late. But having moved up the ladder and worked with the professional cockup makers more closely, I can see even the above was a gentle lucky escape.
Anon, because, I am being rude about people I work with still.
"Oh and that your new shiny servers actually fit in your new standard rack size and dont need ones the length of mars "
ALWAYS specify 1.2m deep racks - that way there's plenty of room behind for cable trays and suchlike without having to fart around dodging mounting kits.
900mm ones are for comms kit, not servers.
Yup, agreed: the most effective system I ever came across was little plastic tags that could only be removed with wire cutters, combined with an indelible fibre-tip pen with which you hand-wrote the labels. I look at Dymo-style labels and can't help thinking that someone has too much time on their hands.
"Indelible" labels tend to be anything but, long term. I've lost track of the number of such things I've run into in cabinets which have become totally illegible.
Laminating labels are great and portable labellers are cheap. Stay away from anything which uses thermal printing on paper as it _will_ fade out over time.
Some labels can contain a RFID chip. If you're setup to handle these, they're extremely useful (many have 200bytes or so of storage)
My cables get 4 labels per cable, the outer most on each end indicates what it plugs into, the innermost on each end indicates what it plugs into on the other end of the cable. The last systems my co-worker installed he said took him about an average of 1 hour per server for the cabling/labeling (3x1G cables, 4x10G cables, 2x8G FC cables, 2xpower (44 labels) maybe someday I'll have blades). Fortunately he LOVED the idea of having 4 labels per cable as well and was happy to do the work.
I also use color coded cables where possible, at least on the network side. I'm happy my future 10G switches will be 10GbaseT which will give me a very broad selection of colors and lengths that I didn't have with the passive twinax stuff.
Use good labels too, took me a few years before I came across a good label maker+labels. Earlier ones didn't withstand the heat(one of my big build outs in 2005 had us replacing a couple thousand labels as they all fell off after a month or two, then fell off again). I have been using the Brady BMP21 for about the past 8 years with vynl labels(looks/feels like regular labels, I've NEVER had one come off).
Another labeling tip that I came across after seeing how on site support handled things. Even though my 10G cables were labeled properly it was basically impossible to "label" the 10G side on the servers themselves, with 4x10G ports going to each server (two sets of two, so it's important which goes to which port still), I did have a drawing on site that indicated the ports, but the support engineer ended doing something even simpler that I had not thought of (at one point we had to have all of our 10G NICs replaced due to faulty design), which was label them "top left" "top right" "bottom left" "bottom right", for connecting to the servers(these NICs were stacked on each other so it was a "square" of four ports across two NICs). Wish I would of thought of that! I've adjusted my labeling accordingly now.
Also I skip the cable management arms on servers, restricts airflow, I just have semi to-length cables so that there is not a lot of slack. Cable management arms are good if you intend to do work on a running system(hot swap a fan or something), but I've never really had that need. I'd rather have better airflow.
Wherever possible I use extra wide racks too (standard 19" rails but 31" wide total) for better cable management. In every facility I have been in power has always been the constraint, so sitting two 47U racks in a 4 or 5 rack cage still allowed us to max out the power (I use Rittal racks), and usually have rack space available.
Also temperature sensors, my ServerTech PDUs each come with slots for two temp+humidity probes, so each rack has four sensors (two in front, two in back), hooked up to monitoring.
I also middle mount all "top of rack" network gear for better cable flow.
Me personally, I have never worked for an organization that came to me and said "hey we're moving data centers". I've ALWAYS been the key technical contact for any such discussions and would have very deep input into any decisions that were made(so nothing would be a surprise). Maybe it's common in big companies, I've never worked for a big company(probably never will who knows).
As an alternative to labels, you can just ask the devices what is plugged in at the other end if you configure your systems properly and buy the right kit. With HP smart racks they know what rack unit they are in and which power sockets they are connected to, and you can create a 3D model in the software to see the data centre. With network cables the functionality has been there for years to just query the port.
You do seem to love labels though, so I'll leave you be :)
query the port...that doesn't work so well if the cable is not connected though.
The system needs to be able to be used in an offline manor, finding what is plugged into what online isn't too difficult, but when adding/moving/changing stuff once stuff is unplugged it's helpful to know what cable goes where.
Electronic labelling should of course be used where you can (so you'd set the port names of your remote-control power bars with the right information).
Electronic labels don't work when the power's off or the network's broken, though. Physical labels come into their own when everything's gone pear-shaped and you're on the phone to the "intelligent hands" guy at the data centre, telling him he needs to move a particular cable from somewhere to somewhere else.
I've generally seen the wider cabinets used for the comms cabinet (i.e. where the switches and routers sit) - they're a godsend as you have so much more junk to fit in there. Standard size cabinets are fine for the cabinets that just hold servers.
The temperature/humidity probes can be fun to mount; I once started getting alarms for high temperatures in a cabinet, and when I checked it out someone had added a socking big Cisco router ... with the efflux of the cooling system venting directly onto the environmental monitor that was mounted in the back of the rack.
If you're taking the opportunity to replace certain systems/subsystems, this is an absolutely awesome time to do a disaster recovery drill ... since that's essentially what you'll be doing for the migration. Unless you are spending severely large monies on fat pipe(s), moving multiple terabytes over a VPN still won't be as quick as other options (sneakernet an array, or even better, set up a replicated backup solution between your office and DC (but seed both devices at the office first) ... once the DC is operational, reverse the data flow ...)
To all who mentioned the cage nut insertion tool and especially Alan Brown for linking the picture. THANK YOU! Holy cr@p on a cracker I never knew such a delightful little device ever existed. Yes, I know, bad me, only moved about 20-odd data centres or parts thereof in my career and donate enough blood to be considered an expert at it.
Unlike others that didn't know what those things were for, I am a bit of a pack rat and have a bag of about 30 of them here, so I will no longer be a blood donor at the DC.
Excellent advice on the labeling too. I remember one particular session where my partner and I created several hundred patch cables for a new DC deployment and we carefully installed clear heat shrink tubing prior to crimping the ends so that we could use a Brother label maker to label everything as we deployed them. Then we would hit the ends with a blow dryer and viola! Yes, Brother's labels are (were then) thermal paper essentially and all our labels went black upon heating with the blow dryer. Doh!
I subsequently acquired preprinted bar coded labels and bought a bluetooth bar code scanner and wrote an app that worked with my BlackBerry to scan either end of the cable to look up a database that detailed what it was connected to.
Yeah, yeah, BlackBerry, blah, blah, I'm Canadian and it was 2001 and the app was written in Lotus Notes, because it WORKED, quickly.
Let the flames begin...
--Pete
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