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118

Please call a cabling contractor in to spend a day or two onsite to "dress" your cables. I used to spend time dealing with this type of work on my own, but realize that cabling contractors are faster and more organized. A good cabling contractor is better at this than you are! They will have the right resources to tag, test, get custom lengths, dress ...


118

In no particular order here are some suggestions that have been helpful to me over the years- Can any of the equipment in those racks be eliminated, upgraded or consolidated? It's hard to tell what's there, but in my experience these kinds of messes tend to be aggravated by gear that should have been pulled out years ago. Once you've got some idea of the ...


73

This is a strange question, but I'm gonna attempt to answer it anyway. All electrical fires must be extinguished carefully. Especially if they're still live. Fire departments will all recommend the use of a CO2 extinguisher. In a datacentre environment, however, I'd (But I don't recommend you) do one of two things. Hit the EPO (Emergency Power Off) ...


64

If your servers use front to back flow-through cooling, as most rack mounted servers do, leaving gaps can actually hurt cooling. You don't want the cold air to have any way to get to the hot aisle except through the server itself. If you need to leave gaps (for power concerns, floor weight issues, etc) you should use blanking panels so air can't pass ...


53

A co-worker and I recently cleaned up a mess that was pretty bad (I might post pictures later if I get some time) and I wholeheartedly disagree with the contractor approach. You will learn significantly more about the system itself and what deficiencies it has if you do the work yourself. Also when you make a mistake, as you or any other mortal is likely ...


52

What'cha talking 'bout Willis? You can get 48V PSUs for most servers today. Running 12V DC over medium/long distance suffers from Voltage Drop, whereas 120V AC doesn't have this problem¹. Big losses there. Run high voltage AC to the rack, convert it there. The problem with 12V over long distance is you need higher amperage to transmit the same amount of ...


45

You need to apply and be granted your own IP allocation by your local registry like RIPE or APNIC. They require annual fees, and you need to justify your requirement (yours is legit). They will assign you an Autonomous System number and a range of IP addresses. You must then find people to peer with (in a datacenter usually), preferably more than one. You ...


44

My sympathies to you. I was tasked with a similar problem for a number of cabinets, equally as horrendous. The approach I took was as follows: Use a spread sheet to make a list of which port is connected to which port on which piece of equipment (arduous manual process of cable tracking). Try to use a spread sheet cell to represent a port, and order ...


43

Use cables as close to the correct length as possible. Spare cable should be coiled away from the concentrator - so spare power cable gets coiled next to the machine, not the powerstrip, and spare network cable next to the machine, not the hub. Don't be stingy with cable ties, be they zip ties or velcro pulls. When in doubt, use an extra, and don't ...


43

Here is a list of questions I made for myself last time I went datacenter shopping: Explain what it would take for sprinklers to go off on our equipment. What will remote hands be willing to do? For example, install hard drives, rotate tapes… Are your remote hands available 24/7/365, average wait time for them to get to the cage after filing a ticket (How ...


40

Recommendations on server room temperature vary greatly. This guide says that: General recommendations suggest that you should not go below 10°C (50°F) or above 28°C (82°F). Although this seems a wide range these are the extremes and it is far more common to keep the ambient temperature around 20-21°C (68-71°F). For a variety of reasons this can ...


40

There are various Government and Industry programs that will provide Hashes of "Known Bad" material (eg CP) to hosting providers. You can then hash the files on your servers and compare. Below are a few that I know of: HashKeeper Discontinued, ran by the US DoJ http://www.nsrl.nist.gov/RDS/rds_2.44/Hashkeeper-RDS244-split.zip DCMEC HVSI Run by the ...


38

While time-consuming, removing everything altogether and putting it back in the new location is the best way to move a server. Trying to take shortcuts will only risk bending your rails, making them unusable. (Bent rails are hard - if not impossible - to bend back.) Never mind the possibility of dropping your server outright, possibly damaging yourself, ...


36

Here's a bit of information not generally published and at times even denied - the insulation used in most electronic components will burn and burn rather well once a suitable temperature has been reached. This includes the material circuit boards are made of, as well as the lacquer used to coat most components. Some types of insulation, once lit, will add ...


35

Who said that "bulletproof hosting" is expensive? PRQ, the company that hosts thepiratebay.org, offers dedicated servers for less than $200 a month and simple web hosting for $10 a month. From their website: Refugee hosting Our boundless commitment to free speech has been tested and proven over and over again. If it is legal in Sweden, we will ...


33

Because they don't need to be located somewhere land/real estate is expensive. Tall buildings are cost effective when the expense of the structure is less than the cost of the footprint.


24

logstash is a tool for managing events and logs. You can use it to collect logs, parse them, and store them for later use (like, for searching). Speaking of searching, logstash comes with a web interface for searching and drilling into all of your logs. http://code.google.com/p/logstash/ It's still rather early in development, but sound very promising ...


24

Context is everything... There's no blanket answer. If you're trying to ask: "what differentiates an expensive switch from a low-end switch?" or "is there a reliability difference between a high-end switch and an inexpensive switch?" The answers are "feature-set" and "maybe", respectively... I've used a $40,000 switch for the specific purpose of ...


23

Water + Electricity = Disaster Water cooling allows for greater power density than air cooling; so figure out the cost savings of the extra density (likely none unless you're very space constrained). Then calculate the cost of the risk of a water disaster (say 1% * the cost of your facility). Then do a simple risk-reward comparison and see if it makes sense ...


23

Speaking from organizational experience at my last job, a small fire in one rack can turn into a big fire with a whole rack, and very shortly afterwards, the rack next to it as well. Fire spreads fast. Once the insulation jackets of all of those power and Ethernet cables gets involved it travels. It travels really fast. Then the flames start tickling the ...


21

All our production servers are stored on the other side of the world in a solid data center. Man traps, biometric scanners, the whole box and dice. For the machines that are in our office, they live in the server room, accessible only via swipe card. Only the sysadmins have swipe cards that can access that area. In short, if someone physically has their ...


20

It refers to the technologies used that make up your service: your web application language/framework depends on (is stacked on) your web server, which talks to (stacks on) a specific database flavor, and these run on (stack with) specific operating systems. So you might have a stack like this: P PHP M MySQL A Apache L Linux to make up the LAMP stack, or ...


20

A couple of jobs ago, one of the datacenters for the place I was working for was one floor below a very large aerial. This large, thin, metal item was the tallest thing in the area and was hit by lightning every 18 months or so. The datacenter itself was built around 1980, so I wouldn't call it the most modern thing around, but they had long experience ...


19

I've always heard 40%, though I can't back that up. I will say though that you need some humidity to reduce static electricity build up. EDIT: Ah, I found my documentation, good old Sun Microsystems Part No. 805-5863-13, "Sun Microsystems Data Center Site Planning Guide: Data Centers’ Best Practices" Temperature and relative humidity conditions ...


19

Weight isn't necessarily an issue. I'm working in a building with a large datacenter about 1/3 of the way up and across the street from a building with a medium sized datacenter about 11 stories up. I've been in datacenters in pole buildings, bunkers, high-rises, etc. Given a facility and some money, all things are possible. The issue totally depends on the ...


18

Always, always, always take the time to strip out those cables you aren't using anymore. Pull it all the way out of the rack/patch panel, coil it up and put it away (or throw it away, as appropriate). And when you're getting rid of dodgy cables. Cut off one or both ends. They will come back and haunt you if you don't.


18

Take a look a ITwatchdogs. Their weather goose line looks very nice. They monitor temp, light, sound, humidity, etc. Here's a list of vendors (not APC) that have other products. What I use in my data center appears to be a discontinued model. What ever you end up using, make sure that: They use SNMP, not some special protocol. Have remote temperature ...


18

I have never skipped rack units between rackmount devices in a cabinet. If a manufacturer instructed me to skip U's between devices I would, but I've never seen such a recommendation. I would expect that any device designed for rack mounting would exhaust its heat through either the front or rear panels. Some heat is going to be conducted through the rails ...


18

I am no electrician either, but I think you will at least lose the possibility of keeping your server up and running when doing so. On the contrary if you connect each PSU to a different power source, your server will still have an availble power source (hopefully).


18

It's not necessarily more efficient as you increase the I^2R losses. Reduce the voltage and you have to increase current in proportion but the resistive loss (not to mention the voltage drop) of power cables increases in proportion to the square of the current. Thus you need massive, thick cables too, using more copper. Telcos use typically -48V so they ...



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