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Can My Desktop Make It in the Big Leagues?
bionic-john wonders: "I work in an environment where the dollar is more than almighty (who doesn't?). One of my cost savings plans is to use desktop computers as servers. They cost much less, the parts are readily available and/or interchangeable - as opposed to waiting for overnight proprietary or obscure parts from a vendor, and so on. I understand that servers have redundancy on disk and power - but this can be emulated for a fraction of the cost, as well. Is there a performance difference between a desktop and a server with the same specs? Chipsets are chipsets, motherboards are motherboard, and memory is memory -- is there something special about a server other than looking at the rack of blades and feeling special?"
If you don't have much space to spare, I would go with rackmount servers anyway. Some also provide remote administration capability separate from the OS, meaning you can reboot it and such.
US businesses that currently accept chip and PIN/signature
- Disks fail. When you stick a server in a rack and leave it running for 5 or 6 years (unlike your average /.'ers desktop which probably gets a shake-up far more often), you won't regret being able to hot-swap a failed drive on your RAID array with a spare.
- Power supplies fail... To be honset, this isn't nearly as big a deal in the hot-swap arena as the hard drives. However, having 2 power supplies in a server machine means that things are significantly less bad when or if one of them happens to fail.
- Vendor commitment. From those old Compaq Proliants to the new Dell Poweredge machines, they were built to be stuffed in a rack and left untouched (unless something fails... see above). They'll come with hardware that those vendors usually stake their reputation on or even had a hand in building. Even the management software isn't always bad....
While there is something to be said for the "Server-Grade" hardware, and rack mountability at that, there is no good reason why intelligently chosen and configured "Desktop" hardware can't perform as well. The key is to recognize limitations of various components, such as being aware of SCSI vs. IDE specs, and the fact that standard PCI slots prevent total saturation of a 1GB NIC. If you choose your parts wisely, and with your goals in mind, you can save quite a bit of money without sacrificing performance or reliability, and maintaining vendor neutrality.
You are not the customer.
It's only relevant if uptime is key, but with desktops, you generally wont have:
Redundant power supplies
Redundant disks
Hardware raid (other than 0/1)
If that's not important to you, then by all means go for it
-- (appended to the end of comments you post, 120 chars)
In the long run, it comes down to standardization and serviceability. If you've got maybe 2-4 servers, go for it. Otherwise, you're in for TONS of headaches. Desktop lines are changed CONSTANTLY, and you'll find yourself always trying to get a part for something that is discontinued.
Still, you can do it. But I stand by the statement you're a dumbass.
redundancy... speed... noise... that coolness factor you get when you say 'yeah, i'm running quad 64 bit opterons with 4 gigs of ram each. yeah thats right, this bitch has 16 gigs of ram, what you got?' and umm... well thats about it. if your needs dont require you to have dual true gigabit nics, dual or quad processors, a scsi raid array and a space heater/pink noise generator, then get yourself some decient computers with the basics. servers are usually built with better parts (i dont know for sure but i'm pretty sure that the same silicon wafers that make the 2.4 celerons also make the 3.2 p4's, the difference is in the testing - i think, plz correct if i'm wrong) but for the most part they're standard parts.
---- The first point-and-click interface was a Smith & Wesson
More details here.
Bits of experience form my days of administrating a heterogenous network of desktops-as-servers in an ISV shop (disclaimer: I am professional software developer, I did administration because I was most knowledgeable OS geek). Several reasons why you don't want dektops to be servers: * Power supplies. Beleive me, PSUs DO fail. And more hosts you have the higher probability of failure you get. Even if you keep a stock of PSUs in the closet. It still takes you about 20 mins to get desktop/server up and running again, and night failure is far worse. * Rack mounting is not a vendor trick to charge you more money. If you have more than trivial infrastructure, wiring on desktops and "floor-tops" is going to be your favourite nightmare. * SCSI and SCSI raids are just a waste of money on a desktop but it is must have for intense, parallel access of many users to their homes, mailboxes, whatever on server. * not last and not least: having someone working on a server is probably most stupid idea in the whole IT. Whatever OS you use, beleive me, users will find a way to devour 98% CPU time and 99% of memory. That leaves for server applications.. well .. do the math :)
There are many other things, I just came up with whatever came into my mind right now.
my sstream of consciousness
Perhaps you've heard of a little technology called RAID? In most environments where space isn't an issue and you have a real IT staff, you could probably get by with a bunch of consumer-grade parts set up in a reduntant fashion.
In fact, the low-cost "servers" you would get from Dell aren't that much more than consumer-grade parts specifically configured to be ran as servers. The cheapest ones come with IDE and Celerons / Pentium 4s.
When it comes to hardware, you should only buy what you need and enough redundancy to keep running through the installation of the next level of redundancy. Computers depreciate faster than any other expense you could have; they aren't drill presses or factory automation.
Simple economics: if two "servers" cost $1500 each, and you can get "PCs" for $750 each, you can either get four times as many or save half the cost--which can help you move to better equipment as the budget goes along.
I have an "obsolete" low-end server that I use for running FreeBSD. It has SMP, ECC RAM, SCSI disks, a boring but very reliable chipset, extensive documentation, diagnostics software, and a high-quality case and power supply. It is also tested and certified to run all of the popular server operating systems. The manufacturer support is excellent. The video card would suck for a modern desktop, but who cares. It never crashes, it just works. If it does break, I can get parts and service.
Mea navis aericumbens anguillis abundat
What makes this guy a server? I'm no expert, but here's what I see:
- Lots of RAM. Came pre-configured with 1GB, and could handle many times that.
- There's only two 32-bit PCI slots, but four 64-bit slots. Handy if you want to add RAID or Fibre support, a nuisance if you want the more ordinary kind of add-in.
- No built-in sound card.
- No AGP interface. Instead, there's a basic 4MB video interface on the motherboard.
- Massive fans.
Anyway, bionic-john is correct in thinking that a workstation will do as a server, provided only that you don't demand more of it than it's designed to do. (Which is always a question anyway.) I work for a hosting/colocation provider, and I see all kinds of stuff pressed into service as servers: cheap white boxes, Sun and Apple workstations, even an X-Box or two. Ultimately, all computers are interchangable. Specialized computers are just a matter of convenience and cost-effectiveness.well - it turns out that one of my white box servers crapped out on me moments after this article! I do not feel bad, nor do I feel like it should have been a 'server' quality machine. The machine was in fact a 1996 PII, it may have even been a cyrix. $200 later and a couple hours, I rolled out a new PIII-1000..the downside was working on SAT.
The load that these machines take are not much more that what that PII could handle (in fact I think that load handled everything great other than its nightly data mirror)..and the 'MISSION CRITICALITY' -- well that is debateable - I agree with the other poster that 2 for the price of one is a great deal (rough cost estimates, but it is close)
I can see a couple servers in the organization that are mission critical (web/mail) - but for some of the print/file servers - like I said, these little white boxes kick ass running a hybrid linux distro.
Yes - there have been times where PSU's died - but that was probably my own fault - maybe I should replace them yearly? In fact - a couple of the boxes have over a year of uptime - they just crank.
I appreciate your input on all this
PS = a lot of talk about RAID - dont forget there are some great IDE and SATA RAID cards out there - I use a few myself.
I've been running cheap desktop units as servers for email, http and win shares for 5 years. No problems. Just buy decent power supplies, check that all the fans are turning once in a while, and change out the hard disks every year or two.
"Eve of Destruction", it's not just for old hippies anymore...
The correct answer to the question is what is the value of downtime to you. Often a few hours of being offline dwarfs the savings possible from this approach.
There is no question you will have more downtime with desktop hardware - it in just not engineered with 365/24 in mind. You can add in a few extra fans and make sure you don't have any proprietary parts like Dell and HP throw into their desktops, but in the long run you WILL have more downtime.
It's not officially a Good Idea, but is fine for some environments.
Just take into account that server and desktop hardware are designed with different goals in mind. Server hardware is meant for 100% uptime, even in the case of most hardware failures, and have good scalability under high loads, while desktop hardware aims to give you the best bang for your buck, understanding that your data is typically much less valuable.
I'm guessing you'll be using IDE drives.
Some of the more expensive (usually scsi) hard disks and controllers have a battery backed cache that can ensure that your writes are preserved in the event of a power loss. The lack of this requires you to sacrifice a great deal of write performance if you wish to ensure integrity. The sacrifice is a bit less if the hard disk preserves write order, which ensures integrity to the extent that the filesystem is capable, though you'll still lose data. Combining a desktop ups with a desktop server, set up to power down safely before the ups runs out and come back up afterwards, is sometimes enough to let you sleep some nights.
The mtbf (mean time between failure) ratings for hard drives intended for desktop and server use are calculated differently. For servers, a consistent high load is assumed. For desktops, a low load and lots of sleep time are assumed. So a 1 million hour server HD might be equivalent to a 2 million hour desktop HD, and most desktop HD's are rated at like 300000 hours.
Also, mtbf is not an estimate of how long a hard disk will last, just the chances of a fairly new drive going out unexpectedly. Like if they tested new hard disks for 500 hours to weed out the duds, then took 1000 of the survivors and tested them for another 1000 hours, and 4 went dead, they could claim an mtbf of 1000*1000/4=250000 hours AFAIK. But you can be sure most of them won't last that long, that's almost 30 years at full load. Like saying if 4 kids in 1000 die between ages 5 and 15, you can claim humans have an mean time between failure of 10*1000/4=2500 years. The real estimated lifetime of a hard disk may be roughly proportional how long the manufacturer is willing to warranty it for. Hard disks intended for server use tend to be warranteed for much longer.
If you use a desktop, max out the ram to minimize disk use and schedule very regular incremental backups, as full backups will also greatly increase disk use. A desktop server will last the longest if it almost only touches the hard disk to perform necessary writes. And be aware that cheap desktops have a high lemon rate.
If you buy a Dell PowerEdge 400sc, their cheapest line of servers, you're actually getting low end desktop hardware in an easy-access case for the about same price as their similar desktops, plus integrated gigabit. So using a desktop as a server isn't too horrible, if it's not vital.
A good raid 5 file server with scsi drives, plenty of ecc ram, and a reduntant power supply can live almost forever without maintenance. They've been accidentally sealed behind walls without anyone noticing until many years later.
Reliability is the only difference between a desktop and a server system. If you can tolerate an outage every few weeks, go ahead and use desktops. If you need 100% uptime, get a real server, it will pay for itself many times over.
What if a hard drive dies? In a server, you pull it out, pop in a new one, and the RAID array fixes itself. The users don't notice a thing. In a desktop machine, you have to turn it off, unplug everything, open the case, unscrew the screws, unplug the cables, remove the drive, put in the new drive, put everything back together, restore the array manually, and hope you didn't lose some data. And all while you do this, the server is down and nobody can do anything.
Just keep one thing in mind. If you pay too much, nothing will happen. If you get a crappy system, you will get fired.
A coworker did something similar to what you are talking about. While it did save cash up-front, he spent a huge amount of time researching and ordering parts, filling out purchase orders, assembling systems, troubleshooting systems, returning defective parts for exchange, burning in and testing assembled systems. Looking at the total costs, it only made sense if you treated his labor as free. In a rational organization, we would have bought tested and assembled systems. But our management had a fixed budget for labor and a small budget for capital expenditures, which led them to ignore labor costs.
Mea navis aericumbens anguillis abundat
For years, Google was a giant pile of dirt-cheap
no-name PCs. Each one had two IDE drives and a
single Celeron CPU. Failure? Oh yeah, but it didn't
matter at all. The software would just drop the
broken box out of the cluster. Nobody would even
bother to fix the PCs as they died! It was cheaper
to just replace the whole cluster whenever too
many of the boxes were dead.
Now Google is large enough to get a good deal on
custom-built rack-mount hardware. It's still IDE
and cheapo consumer CPUs of course. Assuming that
your server needs are a bit less that Google's,
this option won't be available cheap for you.
I've seen some of the hardware google uses and it's not fancy name brand redundant everything servers. In fact their setups might shock some IT traditionalists. They seem to use standard mother boards mounted on open shelfs(no case), with a psu and an IDE hard drive.
From what I've read about google their philosophy is it's better to have a number of redundant servers, then one critical server.
Most of the posts have been reliability yada yada...
Here are the real differences:
Chipsets are different - and focus on throughput.
RAM accuracy (yes... there is a difference)
Built in pre-failure diagnostics
Redundancy
Hot swapable components
When you look at pressing desktops into server use, analyze the cost of downtime. Let's say you have a sales team hooked to your server - 8 users. Server is down 1 hour. Sales are $8,000/day. You lose 1/8 of your sales for the day. You just lost $1K in revenue plus your time spent fixing. This happens 10 times... you can see where the desktop gets expensive.
-- $G
we just bought five new 2u Dell Power Edge 2850's for 2k each!. That included two 2.8 Intel Xeons, three 36 gb seagate scsi 10K RPM drives (can have 6 total) with a 256MB RAID controlller , dual power supplies, dual gig ethernet, and no OS installed. Thats the price you just paid for a decent workstation. It's a bad idea.
There are differences but most do not really look.
Most cheap desktop motherboards have built-in video using "shared memory" - this is actaully taken from main memory and is a constant interuption to CPU to do what it needs to be done.
Bandwidth of the PCI bus and ACPI forcing all cards to use the same interupt adding to the overhead of the OS to sort out the conflict and order. This can also lead to lockups or frozen IO - I know using 100M NIC with 100M disk controller.
Multiple processors - and I am not talking about the CPUs! Server level parts most have intellegent controllers (ie their own co-processors) This way the main CPU can get work done and not worry about the reading a disk drive.
Now: Does very server have to built to server standards? NO
A old desktop box makes a great firewall, printer server or even departmental webserver. The key here, if it goes down how fast can it be replaced? With a firewall do not build one. Build two, the second just needs to boot and be plugged in. Same for a printer server or small localized webserver.
But if you are crunching data - a database server for example - buy a real server. I like IBM X440 maxs out at 16 CPU (build sets of 4) data busses 256 bits wide not 32 or 64 of most mother boards. PCI-X slots 64bits wide and hotswapable cards, plus maxs out with these at like 100 of them. Though on VMWare's ESX and make a pile of "little white boxes" all virtually.
You have also noted about RAID cards for IDE. besure they are intellegent (Co-processors) or the CPU is doing all the work.
In the end to me real difference between Desktop / Server Class / Servers is CPU loading. How much of the "housekeeping" the CPU must perform.
On desktop machine, the CPU does it all, It watches even byte the goes into and out of a disk drive or netcard. It gives up time to allow the video to share its memory. This all takes away from the base function of running an app. At one point a few years ago - the average machine was using up to 40% of its processing just to keep the screen updated.
Server Class machines have helping processors to off load the CPU. Adding these into desktop box starts the transformation into a server - except missing true server need hotswapable everything.
I have built machines with this in mind of years - My current home machine is dual PPro 200, with highend scsi and highend video (for the time, PCI Bus) working a large database and useing database design tool - it out preforms the 3Ghz P4 I have office, with IDE and shared video. Parts do make a difference.
True Server machines are built differently, PERIOD. Look at the X440 from IBM, look at the top end machines Dell, HP/Compaq you will see the difference.
Yes, they are sell servers that are really desktops in deguess. Dell 400SC small server is the same case and motherboards as Dell 800 desktop series. The difference ECC memory, and a front cover that covers the 2 USB slot and sound ports in the front. Also you can get this for less than matching desktop configuration. I got one for my wife's desktop.
Lastly clustering...
Clustering to me is the same as raid to disk drives. Lots of cheap servers sharing the load acting as a single larger machine. So all of this may be for naught.
Buy quality parts, and everything should be OK. Don't expect a $300 emachine to last out the year.
A few tips:That said, dual CPUs and rackmount cases are a luxury, and if cost is that important, you can skip them. And make sure there is a process in place to check on the health of the server. Even waving your hand behind the box once a week to check how hot the PSU exhaust is can save the business a lot of headache. (Hint: if no air is blowing, replace the PSU, and check the HDDs to make sure they're both still working.)
Also, be wary of Dell. They use non-standard power supplies, so if your PSU goes out, you can't hop down to the local computer store and buy a replacement.
RAID 0 is striping. RAID 1 is mirroring.
I don't know how the rest of the world does it, and I don't really care.
The mail server where I work used to consist of a 733MHz Celeron, branded E-Machines. It was a disused desktop machine from Joe Random (Joe, of course, has a shiny new Dell on his desk to replace it). Complete with a $3 PCI RTL8139 NIC, it was the epitome of cheap.
If any part failed, including the 175-Watt PSU, the machine would die completely.
It'd been that way since I started with the company.
I mentioned it to a higher-up, who happens to be a rather important salesman of moderate technical inclination, and whose sales depend primarily on reliable email.
He insisted that I do something about it, and so I began doing so.
I fought with the RAID adapter in a Proliant that we had spare before I realized why people generally loathe binary drivers under Linux. I looked for another way to connect the hard drives, but the box only had one(!) real IDE channel, and it was consumed by a pair of CD-ROM drives.
I sat and fathomed that for awhile: Big server box, stout steel constuction, Serverworks chipset, ECC RAM, huge cooling, 64-bit PCI, one P4 Xeon and room for a second. Unsupportable hardware RAID. One bloody IDE channel. No SCSI. The sound of nonsensical madness was deafening.
So I just built one. I had a few priorities, like redundant PSU cooling, Pentium 4 (I'm an AMD fanboy, but thermal throttling is your friend, even if the chip is vastly overpriced), redundant storage, good IO performance, and the ability to replace any (or every) part with something that can be sourced locally within an hour or so. Oh, and it has to be cheap.
I also made a list of non-priorities: Don't need a lot of number-crunching ability, don't need redundant PSUs, don't care about multiple CPUs.
"Who makes server mainboards," I asked myself. I answered myself with "Tyan."
I've never read anything but good stuff about Tyan. So I got one of their P4 boards. Not a "server" board, but one of their lesser (single-CPU) models which were hopefully developed by the same engineers. Two channels of SATA RAID, four DIMM slots, very few other built-in goodies, except for two additional PATA ports.
It supports dual-channel ECC RAM, so I picked up a couple of quarter-gig sticks of that. Could've gotten more, but remember, this is a -budget- server. (It seldom swaps, and when it does, the disks are fast enough to make it a non-issue.)
Also picked up a couple of Western Digital 80GB SATA drives, because Moving Parts Are Important, MMkay?, and at the time they were the only ones still offering a 5-year warranty. This machine is supposed to live longer than that before it is outgrown.
And for good measure, I included a Pioneer DVD-R for offline backups. I hate tapes.
I tossed it all in the cheapest black case I could find (newegg, $24, shipped). I threw away the included PSU and replaced it with a big Antec Truepower.
Killed the hardware RAID in favor of Linux's software RAID1. I have no intentions of ever marrying a computer's software to something as general and failure-prone as a modern motherboard - out-of-the-box RAID is a great way to fuck yourself at disaster-recovery time.
It runs Gentoo, and and filters and tosses mail something like twenty times the rate of the old E-Machines consumerbox (which had buried itself in backlogged mail a few times).
We've got redundancy of cooling and storage, we've got a graceful fail-safe on the CPU fan, and we've got a disaster plan that includes being able to find parts from the mom-and-pop shop down the street, or mounting the SATA drives in that wretched Proliant with a PCI controller, or (at worst) setting up the Proliant's DVD-ROM and one of its 80gig drives as master/slave and restoring from DVD-R.
I'm pleased with it. It was cheap. It went together slicker than greased shit. I don't think it's going to fail anytime soon, but if it does, at least I don't have to worry abou
Kid-proof tablet..
This is how most IT departments start, and it's a normal process of evolution.
... or it may not. I have seen a couple of
In the beginning, there isn't much money available, so most places cobble together 'servers' from spare desktop components, and throw them up in a closet somewhere. That generally works okay, and the company realizes that they like having servers, so over time, the installation grows.
As it gets bigger, the lower reliability of desktop components will start to become apparent; servers will go down, hard drives will fail. It's just statistics; given enough samples, the lower quality of the cheaper components will start to make itself felt.
Gradually, as IT departments grow, they tend to migrate towards better and better hardware. The really big outfits tend to use Dell and Compaq. Compaq in particular sells very, very expensive machines, which are very well engineered and hardly ever break. But you pay through the NOSE for this kind of service.
So how do you know how much to spend on your servers? When you gain the ability to numerically measure how much it costs you when they fail. When your department and company mature to the point that you can accurately measure costs of downtime, then with management's decision on acceptable risk levels, you'll have a pretty good idea of what you should be spending on servers. Many big companies find that the cost of downtime is appalling, when they actually are able to measure it, and that the cost of even very expensive servers is minimal in comparison, so they buy the best stuff they can find.
But until you can measure it, IMO you're fine with desktop components, as long as you buy GOOD ONES. Don't skimp on your drives, and make sure you have good cooling for them. Buy server cases; you can get good ones for a couple hundred bucks that will hold a billion drives, and then make sure to buy good cooling; you may want the boxes that mount 3.5" disks in 5.25" slots, with fans and hotswappability. I usually buy PC Power and Cooling power supplies for servers; even the Silencers are fairly loud, but they are very robust and well-built. Many of them are dual supplies in one box, which improves reliability even more. That's a lot of fans in each machine, so you may want to pick up a spare or two with each machine you buy. (Tape them inside the case). And the noise level, particularly once you get a number of them, will be high... but think of it as the sound of reliability and you won't mind it too much. Also note that when you get past a few machines, or if you spend a lot of time in server rooms, you should wear ear protection. I have worked in big colo facilities that were absolutely deafening, to the point that things sounded muffled when I left. That kind of noise DOES DO DAMAGE, and you want earplugs.
Make sure you understand exactly what onboard network chipset you are buying: you most likely want an Nforce3 or an Intel, um, 865 or better, I think it is... where the network card is directly on the northbridge, so you can get the true gigabit speeds. When they are on the Southbridge, and look like they are PCI devices, you can't run gigabit full out. And never buy a motherboard that uses Realtek 8139 networking, they are garbage. They make the CPU work way too hard, and are NOT good for server machines.
What you will end up with is a whole room full of Frankenclones, but if you've been smart and spent your money on good stuff, it'll be almost as reliable as the Dell/HP/Compaq/IBM clusters for a tiny fraction of the price. And you'll be able to get replacement parts anywhere. But you probably WON'T have spare parts on hand to fix things, unless you've been unusually clever in your design, because each new generation of machines will be different than that last, and you won't be able to use the same replacement parts interchangeably.
Someday, when you find out what downtime costs you, the extra cost of the big label servers may suddenly look wonderful
By the time you've bought a desktop with all the high performance, high reliability options you'd need for a server, you've bought a server.
Until last year, we had a very good run with using pretty standard machines as linux web and file servers that were accessed constantly over a LAN. The only things that needed replacement were harddisks (so ensure you perform nightly backups to another machine on the LAN), and the occasional birthday present of extra RAM or bigger harddisks.
This year we noticed Dell had very good rates for renting their rack servers, so we grabbed a couple, and will upgrade them on a 18-24 month basis. The affordability of these makes them much cheaper than buying a desktop machine, and the Dell warrantee/support has in our experience been sufficient when we've had problems (e.g. another damned harddisk crap-out).
So now, we have the leased rack 2.8ghz servers for our webservers, and our trusty P~500s still keeping up fine with our file serving, mail, and routing needs, etc (Thanks Linux... ).
I have a PII which is as much as server and a quad xeon (works fine as a webserver, no downtime in the past year due to parts (only had it for a year)).
There is no distinct line between server hardware and desktop hardware. A lower end server is easily build from decent desktop components. The bottom line is: buy good hardware.
Don't skimp on the harddrives, but go for reliable ones. SATA Raptors are as reliable as many SCSI drives, and go in any modern desktop. RAID5 them. RAID5 in software isn't much of a CPU hog in modern machines. RAID5 in hardware is faster, but more expensive. Fit to budget.
Hotplugging SATA is not really supported (tested) in Linux, but expect it to mature. When a drive fails at this moment, downtime is unavoidable. In the near future, expect this to improve.
As for the mobo, memory, network, case. Get quality stuff, but don't go overboard. Onboard vga is fine for your purposes: it will act as a server.
Depending on your needs, backup media need to be considered. Put DVD burners in the server. Backup often. When you need more storage, portable harddrives are great. You need more than one.
Most important: (stress)test your equipment before putting it to use. Most broken hardware is broken from the beginning. Failing hardware is much less likely. The biggest difference between so called server hardware, and desktop hardware is the amount of checking it had before it leaves the factory. So do that yourself.
the pun is mightier than the sword
You are not considering the actual cost of owning and running these machines, only the initial cost of hardware. If you learn how to do a proper analysis of the costs associated with each machine over a 3-5 year period, the typical server lifespan, you will find that purchasing an entry level server will be far less expensive. Better memory (ECC), server chipsets (Intel 7xxx vs Intel 865 for example), and chassis designed to provide adequate airflow for a server is a bargain compared to downtime while you fix your Dimension "server" every couple of months.
You can do a 1U P4 3.0 with mirrored Enterprise quality SATA disks and 1GB of ECC RAM for well under $2000. Take a look at the Intel SR1325TP1-E server platform. It's the server chassis with proper cooling with an Intel TP1 board installed. The board has dual onboard nics and the chassis has about five fans. Very nice, and runs $500. Add the CPU for about $200, memory, and disks (SATA, CD, floppy) and you are done.
I assume USB is to make it removable, but for that to do any good, you need to actually remove it, which means having at least one other USB drive to swap in when the one is off-site. If the budget doesn't allow for that, and you're just going to leave the backup there on top of the server all the time, then save yourself some money and mount an IDE drive in the case, and take advantage of the better speed to get daily backups done more effectively. Alternatively, do on-site daily backups across the network to an old machine otherwise destined for recycling but with a new large hard drive; that'll give you better disaster recovery ability if the main server dies and takes its drives with it.
If you don't need a UPS, make sure you at least have a surge supressor.
Please ignore that comment. You do need a UPS. Skimp on the specs and buy whatever's on sale with rebates at Best Buy this week if you must, but any machine you're going to call a "server" needs at least a few minutes of battery power to protect its data from sudden power outages and its electronics from power slumps.
http://alternatives.rzero.com/
Just don't think you're getting power filtering in a UPS; unless it's an "online" model and costs thousands of dollars, you're NOT.
I bought an APC RS1500 ($400 CDN, 1500va), thinking it'd do power filtering. Well, it does, except that it doesn't do power filtering within a 35w range, if I recall correctly.
According to APC, on 120v power, it has to go above 138v before it tries to filter by cutting voltage by 12% (Not dynamic, it just cuts whatever it gets by 12%). If it drops below 98v, it just boosts it by 12%. That's it.
RAID-1, you mean; RAID-0 is striping (hence 0 redundancy). And yes, anything even vaguely important should be on a RAID array in addition to backups. RAID doesn't help much when your controller freaks out or you hit a fs or user error.
Unless you're willing to trade off warranty, latency and quality against sequential transfer rate and storage, this means go SCSI.
Buy decent fans (twin ball bearing or so?) and monitor them. If noise isn't a concern, this might be a good application for Delta's more extreme fans
On a 1U rackmount, your case fans will most likely be your CPU fans too. Pair of Opterons? Fit passive heatsinks and a bunch of 15kRPM case fans, should be sorted.
Do they make those in 64GB versions now? No? I'll just use another RAID array then, thanks.
Depends what your files are and how you're accessing them; do you want to have to hit disk for every access? With a lot of clients (which is kind of the point with a file server), a lot of memory is practically a requirement.
A good kernel should avoid this, and HTT can help, but when you can get a well kitted-out 1U dual 1.4GHz PIII for under £500, why not?
My local computer store doesn't sell 1U PSU's. Dell do however support redundant ones; I'll take that over downtime while I replace a single one, however cheap/available.
I can't speak to other brands of machine, because we only have Dells, but insist on proper monitorability.
Reid Maynard wonders: "I work in an environment where the dollar is more than almighty (who doesn't?). One of my cost savings plans is to replace the desktop computer with an abacus. They cost much less, the parts are readily available and/or interchangeable - as opposed to waiting for overnight proprietary or obscure parts from a vendor, and so on. -- is there something special about a desktop computer other than looking at the blinking lights and feeling special?"
-- www.globaltics.net
Political discussion for a new world