[CentOS] Central file server advice please

[Ted Miller]

John Bowden wrote:
> I have a Gygabyte GA-7N400 PRO2 with a 2.6 mHz Athlon cpu. I want to set up a 
> central file storage for 2/3 users using 6/7 machines. A mixture of win2k, XP 
> and various Linux distros (my home network). It will be used to store files, 
> (docs, music and DVD ) for all of these machines, print server, (two 
> ink-jets), mail server and later on  a myth tv set up. Would SAMBA be the 
> best option for the file and print serving ?

Probably

> The mother board has 2 X IDE channels, 2 X IDE channels with raid and 2 X SATA 
> raid channels, that's up to 10 hard drive devices. The IDE raid chip is a 
> GigaRaid IT8212F chipset. It supports raid 0 or raid 1 and raid 0 + 1 and 
> JBOD. The SATA raid is a Silicon Image Sil3512. It supports Raid 0 or 1. 
> Would I get better speed performance using the chips to manage the raid or 
> using software raid?

Some digging on Google seems to show that the IT8212F chipset is a 
"halfway" hardware RAID that offers some performance improvement over 
software RAID.  The Sil3512 chipset appears to be pure "fakeraid", in which 
case you are better off putting it in non-RAID mode (in your BIOS) and 
using software RAID.

> Oh and I will be using the CentOS 5 install dvd. Any advice from the list 
> would be appreciated.
> Thanks in advance, John

The other consideration is migration.  If your motherboard dies some night, 
you can take Linux software RAID disks, transplant them onto another 
motherboard, jump through the setup hoops, and be back in business (because 
the RAID is tied to Linux, not the motherboard).  If you use the 
motherboard chips for RAID at all, that will not transfer to another 
motherboard (except possibly if you get another motherboard with the same 
chipset and BIOS).  Even if you migrate in a non-failure situation, you 
will not be able to move the drives to another motherboard (mobo) until you 
either
1. copy the data to another drive somewhere
    install old drives on new mobo
    set up drives on new mobo in new RAID array
    re-sync drives
    copy data from temporary drive back onto array
or
2. Set up new mobo with new drives
    Do initial setup/sync on new array
    copy entire drive contents from old machine to new machine over network

Compared to connecting drives to a new mobo and having a new install of 
Linux recognize the array and set it up for you, there is quite a bit of 
difference in convenience.

My cursory Google search did not give me any data about how much 
performance improvement you would get from the hardware in the ITF8212F 
chipset, as opposed to an all software solution.  If mass throughput is not 
your primary goal (e.g. serving multiple video streams at once without any 
glitches), software RAID may take a little longer to set up at first 
(though I believe you can do it as part of your install, if you answer the 
questions right), it may be easier to live with later on.

Ted Miller
Indiana, USA