The S in RAS stands for sevicability. Meaning when the server requires maintainance, repair, or upgrades, what is the impact? Does the server need to be completely shut down (like a PC), or can you replace parts while it's running (hot-pluggable).

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Thanks for the correction - can't say I'm a server buff, so I took the definitions at face value. The text on page 3 has been updated.

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Looks good. Little history of progression on the S of RAS: disk drives were the first, and the industry sees a large proliferation of RAID configurations with hot swappable drives without any system performance degradation. High end servers have redundant/hot swappable power supplies (Dell brought that en masse to Intel servers). Recently, even CPUs have become hot swappable, something that's been around for a few years on IBM's zSeries mainframes and now pSeries servers (Power5+).

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Great article. I believe the article also need to include the impact of software when choosing hardware. If you look at some bleeding edge software infrastructure employed by companies like Google, Yahoo, and Microsoft, RAID, PCI-x is no longer important. Thanks to software, a down server or even a down data center means nothing. They have disk failures everyday and the service is not affected by these mishaps. Remember how one of Google's data center caught fire and there was no impact to the service? Software has allowed cheap hardware that doesn't have RAID, SATA, and/or PCI-X, etc to function well and no down time. That also means TCO is mad low since the hardware is cheap and maintenance is even lower since software has automated everything from replication to failovers.

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Our focus is mostly on the SMBs, not google :-). Are you talking about cluster fail over? I am still exploring that field, as it is quite expensive to build it in the lab :-). I would be interested in what would be the most interesting technique, with a router which simply switches to another server, or with a heartbeat system, where one server monitors the other.

I don't think the TCO is that low for implementing that kind of software or solutions, and that hardware is incredibly cheap. You are right when you are talking about "google datacenter scale". But for a few racks? I am not sure. Working with budgets of 20.000 Euro and less, I 'll have to disagree :-).

Basically what I am trying to do with this server guide is give the beginning server administrators with tight budgets an overview of their options. Too many times SMBs are led to believe they need a certain overhyped solution.

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Well, if the server is in house, its no biggie, but if that server is acrossed the country (or world), then perhaps paying extra for that 'overhyped solution' so you can remotely access your BIOS may come in handy ;) In house, alot of people actually use in-expencive motherboards such as offered by Asrock, paired with a celeron / Sempron CPU. Now, if you're going to run more than a couple of VMs on this machine, then obviously you're going to have to spend more anyhow for multiple CPU sockets, and 8-16 memory slots. Blade servers IMO, is never an option. 4,000 seems awefully low for a blade server also.

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I don't thing google or Microsoft runs their financial software on a big farm of small, inexpensive computers.
While the "software-based redundancy" is a great solution for some problems, other problems are totally incompatible with it.

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Virtualization is the way of the future. Server admins have been implimenting this for years, and if you know what you're doing, its very effective. You can in effect segregate all your different type of servers (DNS, HTTP, etc) in separate VMs, and keep multiple snapshots just incase something does get hacked, or otherwise goes down (not to mention you can even have redundant servers in software to kick in when this does happen). While VMWare may be very good compared to VPC, Xen is probably equaly as good by comparrison to VMWare, the performance difference last I checked was pretty large.

Anyhow, I'm looking forward to anandtechs virtualization part of the article, perhaps we all will learn something :)

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I am pretty amazed that they did not mention the cost of power in the TCO section.

The cost of powering a server in a datacenter can be even greater than the TCA over it's lifetime.

I love the people that say...oh a got a great deal on this dell server...it was $400 off of the list price. Then they eat through the savings in a few months with shoddy PSUs and hardware that consume more power.



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Page 3:

"Facility management: the space it takes in your datacenter and the electricity it consumes"

Don't overhype power, though. There is no way even a $5,000 server is going to use more in power costs over its expected life. Let's just say that's 5 years for kicks. From this page, the Dell Irwindale 3.6 GHz with 8GB of RAM maxed out at 374W. Let's say $0.10 per kWHr for electricity as a start:

24 * 374 = 8976 WHr/Day
8976 * 365.25 = 3278484 WHr/Year
3278484 * 5 = 16392420 WHr over 5 years
16392420 / 1000 = 16392.42 kWHr total

Cost for electricity (at full load, 24/7, for 5 years): $1639.24

Even if you double that (which is unreasonable in my experience, but maybe there are places that charge $0.20 per kWHr), you're still only at $3278.48. I'd actually guess that a lot of businesses pay less for energy, due to corporate discounts - can't say for sure, though.

Put another way, you need a $5000 server that uses 1140 Watts in order to potentially use $5000 of electricity in 5 years. (Or you need to pay $0.30 per kWHr.) There are servers that can use that much power, but they are far more likely to cost $100,000 or more than to cost anywhere near $5000. And of course, power demands with Woodcrest and other chips are lower than that Irwindale setup by a pretty significant amount. :)

Now if you're talking about a $400 discount to get an old Irwindale over a new Woodcrest or something, then the power costs can easily eat up thost savings. That's a bit different, though.

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