Can anyone explain to me how does colocation work? Why is it so expensive? What does U1 U2 and all that stuff mean? :(

1U, 2U, 3U, etc means the amount of space a server takes up. Go to apple.com and look at the Xserve - that's a 1U server. A 2U server is double the height of a 1u and so on.

Colocation means that you are sending the server you own/bought to the data center for it to be housed/served there. Instead of dedicated (you don't own it), colocated, you own it.

Hi DHerman,

1U is equal to 1.75". Rack mounted servers are measured in U (stands for unit) and therefore most colo providers measure colocation space in a U.

Colocation means you send your server to a professional (hopefully) data center to host. This provides you with redundant power backed up by UPS and generator and a connection to the Internet. Different providers handle the connection differently. Usually the data centers don't sell less than a cabinet or half cabinet. Some sell bandwidth, some just provide a connection to the providers cabinet or router.

Do your homework before choosing a provider. Pay attention to several things...

1. Quality of the data center. Some are definately better than others.
2. If you need a small amount of bandwidth, go with a provider who offers such connections.
3. Do they provide support? If so, how do they charge for the support?
4. Who are their bandwidth providers? Again, some are much better than others.
5. Do they offer a SLA? (Service Level Agreement) (Typically a guarantee of minimum service)

Price is always important but shouldn't be the only criteria. Once you determine your needs, you can then pick the provider who fits your needs the best.

Colocation isn't always expensive (guess that really depends upon your definition of expensive). The reason for the cost is data centers are very expensive to build and maintain.

Good luck.

hi Brad@rackmy?

Well i knew what colo means what i wanted to know if i buy a U1 i can fit only 1 server there or how much i want :)

if you buy 1U then you can fit a single 1U server. Not just any server. Figure a mini tower is 4U.

1U of space is 1 unit in a standard rack, ie 1.75 inches in a 19" wide rack.

Originally posted by WII-Aaron
if you buy 1U then you can fit a single 1U server.
I've seen 3 'servers' squeezed into a 1U chasis. ;)

Here you go, heres our shell server while I was building and configuring it, plus pics of it in Telehouse Docklands London:

The server being configured, please excuse the cable mess:

http://jamesuh.woaf.net/img/building/half5.jpg

http://jamesuh.woaf.net/img/building/half3.jpg

Rackage:

http://jamesuh.woaf.net/img/th/th7.jpg

http://jamesuh.woaf.net/img/th/th6.jpg

The bottom server is a 1U, others win the image are 2U.

Im not going to tell you how much we pay, but its not that expensive when you think about what your getting.