[K12OSN] Need Help

Rob Owens rowens at ptd.net
Sun Jul 8 12:49:31 UTC 2007


Regarding the server, here's a link to a thread where I describe the
latest server I purchased.  It's a desktop-class machine, pretty highly
spec'd, and it cost $700.

https://listman.redhat.com/archives/k12osn/2007-May/msg00026.html

-Rob

On Sat, Jul 07, 2007 at 07:39:53PM -0500, pogson wrote:
> This is a realistic scenario. We are faced with a problem on an unknown
> battlefield. How to survive?
> 
> 1) Re-think the need to keep some/any of that other OS ('98, 2000, ME).
> If the need to keep is due to fear and uncertainty, it might be better
> to keep one or two working as usual and incorporate them later if, as I
> did, you find Linux meets all needs. Are these machines properly
> licensed? Do you have installation CDs for them? If you have any doubts
> about these last two questions, you should not hesitate to wipe the hard
> drives. You do not need the aggravation of tens of thousands of bugs,
> licence issues, lack of suport, and so on. 
> 
> 2)Try to visit each machine with a live CD like KNOPPIX
> ( http://knopper.net/knoppix/index-en.html ). 
> cat/proc/cpuinfo
> free
> lspci
> ifconfig
> ethtool eth0
> will tell you much. You may find it useful to record the data. The
> MAC/hardware address may be useful for configuring DHCP.
> 
> 3)Study your RAM/CPU speed. You may have enough MIPS on a few machines
> to run an LTSP server as a cluster of a few machines. Instead of
> buying/building a new server, you could save hardware dollars and
> increase reliability by have two or three lesser servers. Management
> will be a bit more complicated, but learning is fun, right? You likely
> want 100 MHz per client and 50 MB per client plus about 512MB extra
> memory on each "server". If you find some candidates for servers, run
> memtest86 on them and check memory bandwidth. Some Celerons and the like
> have pretty good specs but memory bandwidth is incredibly low. A good
> server is something like AMD64 X2 3800 with 1MB cache so look for
> machines with 1000MHz or better and at least 256MB caches. DDR400 memory
> would be fast enough for your setup, 3 gB/s memory bandwidth. If you can
> get a few machines that total up to something like that, upgrade them by
> adding RAM and perhaps a gigabit/s NIC. That will be cheaper than buying
> a good server. You can use the saving to buy a network switch with some
> gigabit ports. Otherwise, a suitable server would likely cost over
> $1000. Using a cluster IN the lab is a bit risky. You may need to cover
> the power/reset switches and place reminder signs to leave them on. If
> you can delay buying the server, you will end with a better system
> because performance/$ keeps improving.
> 
> 4)If you must obtain a new server, please, check out the manual
> including all specs and motherboard flowchart to be certain of hardware
> compatibility and absence of bottlenecks. For example, a 32bit system
> may look like it has the specs you need but you may find a gigabit/s NIC
> on a PCI bus uses all the bandwidth and there is no more for hard
> drives. Many AMD64 motherboards I have studied appear to be able to run
> CPU/memory/a bunch of drives/a couple of gbit/s NIC at nearly full speed
> all day long, which really helps a  LTSP server be snappy. Fortunately,
> competition between Intel and AMD is intense so great prices abound.
> Dual core/dual processor is a huge advantage with LTSP because there are
> plenty of processes to go around to each core/processor. Last year, I
> bought AMD64 X2 3800 for $200 CDN. This year, it is less than $100 CDN.
> Good timing! You can also buy much faster processors. I have always
> built my new servers so I can be sure what is in there.
> 
> 5)Please use gigabit/s cat 6 networking for all servers. One gigabit/s
> line can easily handle your lab. 100 mb/s can too, but you, and your
> users will know when things get busy. Gigabit to 100 mbit switches are
> pretty cheap these days.
> 
> 6)Please use RAID 1 on your server. This is slower for writes
> (installation and saving files) but allows simultaneous seeks for
> simultaneous users/pocesses. Hard drives are about 25 cents a gB for 500
> gB. 
> 
> 7)Around 1999 many PCs began to have NICs on the motherboard. On some of
> these, you can press F8 to bring up a boot menu giving an option of
> PXE/network booting from your server or booting from the hard drive. You
> would not even need to install a boot loader to use that, if you posted
> signs by each computer. Unfortunately, if you have '98, you are in that
> time range where things changed. You can install a boot loader on the
> MBR, but it would be easy to mess up your booting of that other OS. Do
> not forget booting from the CD. You could have CDs hanging on the wall
> which would boot from your server. CDs are much more reliable than
> floppies. Whatever the boot medium, you need a driver for every NIC in
> your place. If you happen to not have a driver, you will need to install
> an additonal NIC.
> 
> 8)If you can blow away that other OS, you have more options: installing
> a bootloader on the hard drive, installing a minimal system (+
> x-window-system and gdm) and connecting via X to the server, or
> installing a complete Linux distro with the option to connect via X to
> the server from the GNOME menu, and dual-booting (please, don't inflict
> that other OS on your students).
> 
> Good luck. I would be glad to help, but I am 500 miles away.
> 
> Robert Pogson
> 
> On Sat, 2007-07-07 at 12:00 -0400, k12osn-request at redhat.com wrote:
> 
> > "Don Gould" <don at myfam.com>
> > Subject: [K12OSN] Need Help
> > To: k12osn at redhat.com
> > Message-ID: <380-2200776712480644 at myfam.com>
> > Content-Type: text/plain; charset=iso-8859-1
> > 
> > To anyone listening,
> > 
> > I am the Technology guy at a small christian school and I have been
> > to to seminars.  I am ready to make the leap to K12osn.
> > What I have :
> > 
> > 30 computers in the lab
> > 24 stand alone
> > 6 networked internet machines
> > all are windows 98, 2000 or ME
> > 9 printers 4 of which work
> > 
> > I need to get a server or build one.  But I need to know what I need
> > in the server.  I nned to keep the win os for stand alone use.  But I
> > will netwok all the machines for K12.  Will I be able to print my
> > windows documents thru the server and do I also need win server
> > software as well as K12? I will use the sever for the internet.  I
> > plan to get one or two netwok printer to serve all my printing needs
> > if that will work.  Feel free to answer all the question I dont even
> > know I need to ask to get this started.  Thanks in advance for your
> > help.
> > 
> > In desperate straights
> > 
> > Don Gould
> > Hollandale Christian School
> > 
> 
> -- 
> A problem is an opportunity.

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