Bits Build your own server

GrahamC:

If you want more Linux guides then I highly recomend that you head over to http://www.howtoforge.com As they have some really great easy to follow guides. Plus the ubuntu forums are really good with plenty of helpful people on them.

 

Thanks I'll take wonder over and see.

 

I'm running a server aswell with pretty much the same functionality atm with Debian (Etch/testing) and it runs like dream.
Gbit connection will allow me to move files at 40MB/s to my pc atm.
Services running atm:

SSH
Webmin
Torrentflux
PHP
MySQL
Apache
FTP
AJAX File browser (tip!)
PHP Systeminfo
Folding@Home (for Bit-Tech team 33346 )

I only used the command line to configure it, but i think the way it's described here is pretty much the way to go for beginners.

Running a server the way you guys described in the article is nice as a project for people to get familliar with Linux.

 

might as well shoot yourself in the foot now and get it over with.

 

dude, don't underestimate the speeds you can get with software raid under *NIX or *BSD systems, might i remind you of the fact that the cpu's in most of those servers only have to run a mere 16mb'ish OS (tried FreeNAS myself, works great but was kinda limited for other stuff) only have to transfer some files, so they don't have to bother running other services like windows would have to do.

Remember you have an even faster cpu doing the XOR calculations needed to manage the RAID set then most Areca,Promise, etc. controllers would use.

Attaining speeds of 70~80 MB/s should be no problem at all for a FreeNAS server running a software raid and gbit lan.

peace

 

I once tested:

Fileserver (iSCSI): AMD Athon 1200, 256MB RAM, Debian unstable, software RAID 5 with an Logic Volume on top.

Receiver: Intel Xeon 2.8GHz, 1GB ECC, Debian unstable.

Link between them: Regular Gigabit link (no jumbo frames) but through a decent switch.

This resulted in read and write times >100MByte / sec (tested by using a 100MB .iso file that I wrote to and from the mounted share from the local HD (IDE). I actually think the local harddrive was the bottleneck. The load on the fileserver never went above 15%CPU and 50MB RAM

 

I completely agree, you may not get the speeds that you would with some high end raid cards, but not everyone can afford those items.

FreeNAS brings NAS boxes to the masses in true opensource spirit (the base for it is FreeBSD).

 

Its not about speed, its about the R in RAID (Redundant Array of Independent Disks)

with software RAID, it is next to impossible to recover the data if the software governing the array or the OS dies, because unlike with a hardware discrete card doing the work, you can't migrate the array to another system. and the software is unique, whereas if the hardware card dies, just put in another and the computer and the array don't know the difference. and with software, you have the CPU overhead, where with hardware there is no overhead and the array appears as a single drive letter, which makes some tasks much easier.

while software RAID may be faster, it isn't true RAID and I would never use it unless it was for processing only, like using twin Raptors in RAID 0 for paging.

 

Sorry to burst your bubble, you can... Mdadm rebuilds arrays based on headers on the disks, regardless of the system they are in (presonally witnessed a mobo change). If your entire system, excluding your HD's fails (power surge), software RAID is safer then hardware IMHO. Also on dedictated server boxes (like this one), the CPU overhead isn't a problem. In workstations I fully agree, get HW RAID cards, but on dedicated boxes, let the CPU handle it.

And I wouldn't call software RAID 'not true raid', it uses the drives redundantly... just like HW raid does...

 

it depends on what software you use, most software is finicky when it comes to rebuilding, and is very easy to screw up, there are a few that do indeed work, such as the one you mentioned, but it still isn't advisable for someone without good knowledge to attempt it. the hardware offers the alternative of being very easy to deal with, and also is (relatively) idiot-proof by comparison.

the other major aspect is rebuild time, because of the complexity it takes much longer for a user to transfer and rebuild a software array then simply moving the disks and card or replacing the card and moving.

mostly my point was coming from the bootable array point of view, if you were using a cheap RAID1 card for the bootable set, and using the software for the larger storage array, that would make sense. but if you were booting off the software array and the motherboard goes, then you're up the creek with no paddle.

 

RAID shouldn't be done without knowledge...

About 4 hours on a 1800 MHz cpu, for a 3*200GB RAID 5 array, so not too shabby IMHO.

Bootable is something else, that requires some extensive knowledge, because the raid tools have to be loaded before the root filesystem is loaded.

 

but since we're talking about using RAID on a fileserver for those without knowledge of bootable arrays, I think a <$100 Syba card is still the better option.

though I may have to use software myself soon for a second array, as the one in the media server is filling up.

 

Nothing prevents you from having the system disk regular, and the data on an array, and then there is no problem. The data drive will be mounted long after the RAID utility will be initialised.

Anyway, there's a reason I didn't talk about RAID arrays in the article

 

Great guide, but how does it hammer any nails? It just goes to show how versatile Linux is, Microsoft is too - providing workstation and server operating systems.

Glider you'll never cease to amaze us with your Linux knowledge!

 

ooo! nice! ... so, uhm, would you mind if I PM'ed you some questions about trying to set this up?

 

Thanks glider for your responce, i was worried i was going to get roasted for my stupidity.
I really wish i was good at things like this, its these types of things id like to improve my knowledge on as its horrible!
Great article!

 

I'm now inspired to re-assign my gf's pc (766 celeron, bout time for an upgrade), however despite being a linux n00b I would like to use a purely CLI setup. It'd just bug me the resources (however small) being wasted on a GUI.

EDIT:
Are there any web based binary usenet clients (Like torrrentflux) I could install on such a machine?

EDIT #2:
Found one! Ninan Looks pretty good too, be a while before I can try it out though

 

the documentation provided with it is pretty thorough, and explains it better and in much more detail than I can. also I've only futzed around with it in kubuntu, never actually set one up for serious public domain use (and thus never bothered with the security steps, just the LAN setup)

 

Thanks glider, that was fantastic. Xubuntu should be downloaded by now, will be servering it up tonight...

+10 votes for more articles from glider.

 

*nix software raid is as fast or faster than the most expensive raid cards and is easier to restore if you know how as the array can withstand the disk controller dying. Which is a big problem if the manufacturer of the disk controller no longer makes that particular controller.

Atm the main bottle neck in file transfers from my ubuntu box is 100Mb/s ethernet and thats without raid.