Talk:XS Server Hardware

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Revision as of 13:11, 22 March 2007 by Gnu (talk | contribs) (One possible XSX hardware)
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Scalability

Doing some quick math based on Argentina Statistics, at the national level you have 5,151,856 kids in K-12 grades in 27,888 public shools, giving ~180 laptops / school (or ~3 servers / school).

Does the internet connection scale for larger schools ? Does a 60 student school have the same access as a 240 student school ?--Wad 00:22, 2 February 2007 (EST)

Good or bad? Don't know.

PRO
Multiple servers could improve coverage, redundancy and available storage.
CON
Higher costs per school (depending on alternatives), multiple failure points and/or administration.

We are deploying just one (overpowered) school server per early trial, and will obtain a better idea of the requirements. The final number may be 120, or 50...--Wad 00:22, 19 March 2007 (EDT)

As a note specific to Argentina, the educational system is split in 4 three-year chunks: EGB I, EGB II, EGB III + polimodal (being only EGBs compulsory). Multiple servers could support 'administrative' layers or frontiers between these different 'levels'—acting like some 'sub-network' division.

This is just a guess-list. Please add at will. PoV is subjective... so a con may sometimes be thought of as a pro depending on the overall context. For example, redundancy could be thought as good if it's simple and straight forward out-of-the-box(es), but if to administer the multiple servers you must do it in a totally different way than when you just needed one, then it can be thought as a con given the penalty to growth.

There is no question that a single school server will be targetting a maximum number of students, the only question is "how many?" I can design a server capable of serving 20 students, which will fail miserably if you try to use it stand-alone in a school of 200. I can design a server which can handle 800 students, but it would be overkill for a school of 30.--Wad 00:22, 2 February 2007 (EST)

One possible XSX hardware

I've been running FC6 on an HP dc5750 (and just ordered another). It can be bought in a standard minitower, or in a set-top-box-style ("SFF") case. AMD chips, ATI graphics, Broadcom gigE. Ten USB slots. Has fans, but they are very slow/quiet in normal operation. I can't hear it in my living room unless my head is very close to it. I bought it with the Athlon64 X2 Dual Core Processor 3800+ (35W max), which reduces the max power/heat by half, and the 80PLUS power supply which is more efficient, thus less power/heat. ($40 and $20 options.) Has two SATA disk slots and 4-way mobo SATA controller. No PATA.

PRO: available from stock, or with a few weeks leadtime for custom config. Quiet, low power, no Microsoft tax (buy the "FreeDOS" version).

CON: ATI chip undocumented and poorly supported (works great for 2D graphics, nothing better). Minor issue when booting from the optional LightScribe DVD+-RW, Linux driver for the ATI chip barfs for unknown reason; solved by adding a cheap Rosewill RC-210 PCI SATA card for the DVD (it also gives you an external SATA port for a faster ext hard drive than USB can provide). Linux has no trouble accessing disk drives on the motherboard SATA - just lightscribe DVD. lm-sensors can't see the motherboard sensors, probably the *%&$$ ATI chip again. (Maybe yr buddies at AMD/ATI can help you with this.)

HP's optional memory card reader (plugs into the floppy slot and a motherboard USB header) does NOT support SDHC, so avoid it. I tossed theirs, and added a cheap YE-DATA YD-8V08 memory card reader and floppy drive, which DOES support SDHC. Newegg.com has it (and the RC-210 SATA).

I've noticed that when plugging in USB or SD cards, sometimes Linux doesn't immediately notice and DTRT. If you plug in something else on USB, then it figures it out. Don't know whether this is hardware or FC6 software problem.