CentOS - Apr 2010 - Slightly OT: which hardware for CentOS file server (Samba, 2 To storage, 50 users)?

Hi,

The language lab from the local university has contacted me. They'd like 
to have a low-cost file server for storing all their language video 
files. They have a mix of Windows, Mac OS X and even Linux clients, 
roughly 50 machines. The files are quite big, and they calculated a 
total amount of 2 To of storage.

I'm not very proficient with hardware, meaning either I'm dealing with 
remote servers in some datacenter, or otherwise I install CentOS 
desktops on any hardware people throw at me.

Since the aim is lowcost, would it be wrong to install that fileserver 
on a no-name desktop PC with a 64bit processor and enough RAM, and then 
simply put 2 x 2 To hard disks in it, either with a mirroring RAID (can 
never remember which does what in 0, 1 and 5) or some rsync script 
regularly copying over the first disk to the second? Or do you have 
something more apt to suggest?

Cheers from South France,

Niki

----- "Niki Kovacs" <contact at kikinovak.net>
wrote:
> Hi,
> 
> The language lab from the local university has contacted me. They'd
> like 
> to have a low-cost file server for storing all their language video 
> files. They have a mix of Windows, Mac OS X and even Linux clients, 
> roughly 50 machines. The files are quite big, and they calculated a 
> total amount of 2 To of storage.
2 TB?
> 
> I'm not very proficient with hardware, meaning either I'm dealing
with
> 
> remote servers in some datacenter, or otherwise I install CentOS 
> desktops on any hardware people throw at me.
> 
> Since the aim is lowcost, would it be wrong to install that fileserver
> 
> on a no-name desktop PC with a 64bit processor and enough RAM, and
> then 
You *COULD* do this, but keep in mind desktop class hardware may give you poorer
performance, especially for fileserver use. You seem to have the storage
requirements down, but make no mention of performance requirements. They are
moving huge files to/from the server, but are they expecting it to happen in a
few minutes or take all day? You mention 50 machines, but how many *CONCURRENT*
connections? The more concurrent sessions you have, the poorer it may perform
due to disk thrashing. A *GOOD* storage controller added to a desktop class
machine on a PCIe bus will do wonders for you.
> simply put 2 x 2 To hard disks in it, either with a mirroring RAID
> (can 
> never remember which does what in 0, 1 and 5) or some rsync script 
> regularly copying over the first disk to the second? Or do you have 
For mirroring, you'll want RAID-1. This automatically keeps both
drives/partitions in sync as the data is transferred, no need for rsync or any
external scripting other than checking the health of your array(s).
> something more apt to suggest?
I'd suggest something more 'yum' like than 'apt'. [1]
> 
> Cheers from South France,
> 
> Niki
Cheers from North Central U.S., 

Tim

[1] A poor attempt at package manager humor. RHEL/CentOS 'yum' vs
Debian/Ubuntu 'apt'. :-)

> Hi,
>
> The language lab from the local university has contacted me. They'd
like
> to have a low-cost file server for storing all their language video
> files. They have a mix of Windows, Mac OS X and even Linux clients,
> roughly 50 machines. The files are quite big, and they calculated a
> total amount of 2 To of storage.
>
> I'm not very proficient with hardware, meaning either I'm dealing
with
> remote servers in some datacenter, or otherwise I install CentOS
> desktops on any hardware people throw at me.
>
> Since the aim is lowcost, would it be wrong to install that fileserver
> on a no-name desktop PC with a 64bit processor and enough RAM, and then
> simply put 2 x 2 To hard disks in it, either with a mirroring RAID (can
> never remember which does what in 0, 1 and 5) or some rsync script
> regularly copying over the first disk to the second? Or do you have
> something more apt to suggest?
>

What value does the language lab associate to these files?
And how is backup done?



Rainer

50 simultaneous users will require more than a bargain desktop PC.

I would go for low-end server hardware, which will get you ECC memory and 
more SATA ports. The cost is probably not significantly more than a _good_ 
quality desktop system.

You may want to allow for some expansion, 2 To may grow into 3 To over 
time. Also plan for backups. You may want to use LVM and leave some disk 
space unallocated to you can create snapshots and make backups to external 
USB drives or another network server while the system is up and running.

My personal criteria:
- decent power supply
- space for 4 3.5" hard drives.
- 4 memory slots, so I can go to 8 Go memory without breaking the bank
- at least a dual-core Xeon or AMD processor which supports ECC memory
- 4 or more available SATA ports on the motherboard
- 1-2 1000BASE-T network interfaces.

You could go for a RAID controller, but RAID1 (mirroring) has little 
overhead in software, and you can buy 2 extra hard disks for the price of 
the controller.

G? (from cloudy Nevada)


On Mon, 12 Apr 2010, Niki Kovacs wrote:
> Hi,
>
> The language lab from the local university has contacted me. They'd
like
> to have a low-cost file server for storing all their language video
> files. They have a mix of Windows, Mac OS X and even Linux clients,
> roughly 50 machines. The files are quite big, and they calculated a
> total amount of 2 To of storage.
>
> I'm not very proficient with hardware, meaning either I'm dealing
with
> remote servers in some datacenter, or otherwise I install CentOS
> desktops on any hardware people throw at me.
>
> Since the aim is lowcost, would it be wrong to install that fileserver
> on a no-name desktop PC with a 64bit processor and enough RAM, and then
> simply put 2 x 2 To hard disks in it, either with a mirroring RAID (can
> never remember which does what in 0, 1 and 5) or some rsync script
> regularly copying over the first disk to the second? Or do you have
> something more apt to suggest?
>
> Cheers from South France,
>
> Niki
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
>

Niki Kovacs wrote:
> Hi,
>
> The language lab from the local university has contacted me. They'd
like
> to have a low-cost file server for storing all their language video 
> files. They have a mix of Windows, Mac OS X and even Linux clients, 
> roughly 50 machines. The files are quite big, and they calculated a 
> total amount of 2 To of storage.
>   
I'd look at using 1TB drives rather than 2TB, the 2TB seem to be too 
bleeding edge and have been too many anecdotal reports of problems.  for 
sure you want to use server rated SATA drives for an application like 
this, such as the WDC RE series, or the Seagate ES series (this has more 
to do with write buffering and consistent error reporting than it does 
to do with performance).

if this system is going to have 50 clients constantly playing videos on 
it, then I'd look at 450gb or 600gb SAS drives, and a lot more of them.

If this is to be a rack mounted system in a data center, I'd probably 
look at a box like a HP DL370, which can hold quite a lot of drives. 
http://h10010.www1.hp.com/wwpc/us/en/sm/WF05a/15351-15351-3328412-241644-241475-3890172.html

put the lowest end single CPU they offer in it, but get the better raid 
controller and a reasonable amount of memory, and redundant PSU.   get 2 
hot spare drives.   if initial requirements are 2TB usable storage, 
thats 4 x 1TB raid10 plus 2 x 1TB spares.  also get two small drives 
(like 72gb sas) for those left-side slots, mirrored for the OS and 
software.   6gb ram is probably fine.   the base model of this system is 
$3300 with a 4-core 2.4ghz, 6gb ram and 4 gigE ethernet ports (you could 
gang these to the switch if their network infrastructure supports ether 
bonding aka ipmp).

OSX should be happy with NFS, Linux clients certainly are, and Samba can 
serve files for Windows clients.

its always strange to see that people want "cheap servers".
Let me tell you it will NEVER pay off.

50 people will kill a low end thing, especially if
you want to do software based RAID, the throughput
that is required by that data coming in and out will
make you users VERY unhappy and then say CentOS is crap.

You need at least some XEON based motherboard, proper ECC
RAM and HARDWARE RAID, anything else will not work.

That said you can buy decent motherboards from the lower
end of INTEL server boards, put a decent CPU into it and
get one of the 4 channel Adaptec cards, splitting data 
and OS onto separate raid channels, they got 2 GB network
cards so you can split the throughput in half.

I know this works because the small school that I look 
after has that setup.


jobst








On Mon, Apr 12, 2010 at 05:53:55PM +0200, Niki Kovacs (contact at kikinovak.net)
wrote:
> Hi,
> 
> The language lab from the local university has contacted me. They'd
like
> to have a low-cost file server for storing all their language video 
> files. They have a mix of Windows, Mac OS X and even Linux clients, 
> roughly 50 machines. The files are quite big, and they calculated a 
> total amount of 2 To of storage.
> 
> I'm not very proficient with hardware, meaning either I'm dealing
with
> remote servers in some datacenter, or otherwise I install CentOS 
> desktops on any hardware people throw at me.
> 
> Since the aim is lowcost, would it be wrong to install that fileserver 
> on a no-name desktop PC with a 64bit processor and enough RAM, and then 
> simply put 2 x 2 To hard disks in it, either with a mirroring RAID (can 
> never remember which does what in 0, 1 and 5) or some rsync script 
> regularly copying over the first disk to the second? Or do you have 
> something more apt to suggest?
> 
> Cheers from South France,
> 
> Niki
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
-- 
File not found! Do you want me to fake it? 

  | |0| |   Jobst Schmalenbach, jobst at barrett.com.au, General Manager
  | | |0|   Barrett Consulting Group P/L & The Meditation Room P/L
  |0|0|0|   +61 3 9532 7677, POBox 277, Caulfield South, 3162, Australia

Niki Kovacs a ?crit :
> 
> Since the aim is lowcost, would it be wrong to install that fileserver 
> on a no-name desktop PC with a 64bit processor and enough RAM, and then 
> simply put 2 x 2 To hard disks in it, either with a mirroring RAID (can 
> never remember which does what in 0, 1 and 5) or some rsync script 
> regularly copying over the first disk to the second? Or do you have 
> something more apt to suggest?
> 
Thanks for all your detailed answers. Seems the story resolved itself in 
a quite curious manner. The lab already has a "sysadmin", e. g. a guy 
who openly claims to be "no computer specialist, but my machines are 
running anyway, better than the ones built by the pros". I asked him if 
he could fill me in on some details, like what should the IP address of 
the server be, netmask, gateway, dns, so that I could integrate it into 
his network. I planned to first make a "dummy" server with my laptop 
just to do some testing, ping around, etcetera. The following 
surrealistic dialogue followed:

- "You know, I can't really let you know this, this is a very special 
network."

- "Yes, but you asked me to install a server in your network. If you 
want me to do that, I have to know some network specifications. For 
example, will the machine be statically configured, or do you plan to 
handle it with DHCP and a fixed address based on the MAC address?"

- "This is neither DHCP nor static, you know, we have an internal 
network." (!)

- "So you can't tell me your network specs, if I get you right. You 
know, when you ask a plumber to install a bathtub or a jacuzzi, you 
ought to tell him at least where your bathroom is, and where he can find 
the water tap."

- "I only asked for a server. I don't know why you have to know all
this."

And so on. In the end, I decided not to bother and just left.

:o)

Niki

Niki Kovacs <contact at kikinovak.net> wrote:
>>
And so on. In the end, I decided not to bother and just left.
<<

I think most consultants have one* of those in their pasts. The trick is to
cut your losses, as soon as possible. You had a narrow escape there.

Best,

--- Les Bell
[http://www.lesbell.com.au]
Tel: +61 2 9451 1144

* Two, just possibly. Three, and you're a slow learner who has no business
being a consultant.