I have a Gentoo box with 3 identical drives* and I want to set up the following software RAID solution:

Drive 1: system
Drive 2 and 3: RAID 0

I had a look at the Linux Software RAID Howto but it is dated 2004-06-03. Is this still relevent? Is there another solution I should be looking at?

Thanks to any responders.

Peter

* Seagate ST3160812AS; 160 GB; SATA 300

look up 'mdadm' (md-admin ... multidisk administration or something like that). it is the replacement for raidtools and as of fc4 it is 'stock' in red hat distros. don't know about gentoo, but you can easily take the mdadm source or rpm and install it for your distro.

i currently use linux software raid to run a mirrored array of 2 disks and a striped (raid 5) array of 4 disks, and i'm crazy happy with it so far.

silicon image chipsets are natively supported by modern linux kernels (even in rpm form), as are a whole bunch of other ones but i'll be damned if i know what they are.

i'm a Sil fan, others are not... either way, get a controller that is recognized by linux without fiddling with a driver -- easiest way to get going. unless, of course, you're working off your mobo EIDE header, in which case u're already running it so no sweat.

to check if u have mdadm already installed, just run [abc@123]# /sbin/mdadm at the prompt to see what pops up.

I installed mdadm and set up my array but I get strange results when I boot up.

First, a boot message:

"mdadm: no arrays found in config file"

Now I do have /etc/mdadm.conf:

---------------------------------------------
DEVICE /dev/sd[bc]1
ARRAY /dev/md0 level=raid0 num-devices=2
UUID=5f79d056:a18f016b:5125e750:9565ed9f
---------------------------------------------

That last two lines are really one line in my file.

Second, my array still comes up ok except that it is associated with the device /dev/md/0 instead of the one I iniitially configured before reboot: /dev/md0. This last one is also what is contained in my /etc/fstab file:

/dev/md0 /vol2 ext3 defaults,noatime 1 2

Here is df output:

/dev/md/0 294G 129M 279G 1% /vol2

Nonetheless,

# mdadm --detail /dev/md0
---------------------------------------------
/dev/md0:
Version : 00.90.03
Creation Time : Sat Feb 17 22:17:21 2007
Raid Level : raid0
Array Size : 312576512 (298.10 GiB 320.08 GB)
Raid Devices : 2
Total Devices : 2
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Sat Feb 17 22:17:21 2007
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0

Chunk Size : 128K

UUID : 5f79d056:a18f016b:5125e750:9565ed9f
Events : 0.1

Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
---------------------------------------------

Can anyone shed some light on any of this? One question I have is how is mdadm supposed to bring up the array in the first place (how is the array detected)?

Peter