RAID newb, 2 drives, mobo raid + Linux CertOS

Alright, here we go. Setting up a Linux box for a phone system and we want to have a RAID setup in the box. I have looked all over for info on this but can't seem to find it so I'm turing to the [H] for some help.

Setup:

Mobo - K8V-MX
HDDs - Segate Barracuda 7200.9 80gig (x2) SATA2

if you need everything else I'll provide it too, anyways, onto the issue.

My Boss knows more about computer then I do but with both of us we don't know much about RAID setups. The question is: Once the motherboard RAID (Not sure if it is software or hardware RAID) is setup as RAID 1 should everything automatically write to both drives?

I've read that I have to setup Linux to see that there are two drives and to write to both of them at the same time. My boss says that the hardware RAID on board will automatically and magically do everything for us, if there is a drive failure shut the machine down, unplug the crapped hdd, plug in a fresh one and the onboard RAID will rebuild the broken hdd.

So, do I need a driver/software for Linux or does the onboard RAID do it all?

Thanks for any info.

I suggest you use Linux Software Raid instead of the "hardware" (really, it's driver-based) raid on the board. It would let you move to another board in the future, and the monitoring tools for it actually work. Look at the man page for 'mdadm'; it explains what you need to do to create an array.

If you run into problems, post back and I'll help you out.

Thanks man. I found mdadm a little bit ago and I'm trying to install it. This is a trixbox machine if you have heard of it. I'm having problems installing mdadm. I've tried yum, rpm and the archives off of the mdadm site tar doesn't like, says something about "This does not look like a tar archive" (I'm somewhat of a Linux newb as well...bad combo) using the argument "tar xvvf mdadm-2.6.tgz". Any help here is appreciated!

You'll have to throw a 'z' in there. 'tar zxvf mdadm....tgz', IOW. Since it's a gzipped tar archive, this tells tar to decompress it first. If you had a bzip2 archive (.tar.bz2 or .tbz2 extension, usually) you'd need to use the logical letter... 'j'.

Did you run 'yum install mdadm'? What did it return?

Alright bunch of stuff. Tried that different argument, didn't work got this for an error:

extracted some files to the correct directory then:

tar: Skipping to next hear
tar: Archive contains obsolescent base-64 headers

gzip: stdin: invalid compressed data-format voilated
tar: Child returned status 1
tar: Error exit delayed from previous errors

back to a prompt. Tried to make install but then I get:

Makefile:54: *** missing separator. Stop.

:-/

//"yum install mdadm" returns:

Setting up install Process
Setting up repositories
Reading repository metadata in from local files
Excluding Packages from CentOS-4 - Updates
Finished
Excluding Packages from CentOS-4 - Base
Finished
Excluding Packages from CentOS-4 - Addons
Finished
Excluding Packages from CentOS-4 - Extras
Finished
Parsing package install arguments
Nothing to do

:-/ Not sure what more I can try.

Thanks for your help btw

PS - Forgot to include that I tried both the 2.5 and 2.6 archives with the same "Archive contains obsolescent base-64 headers" error.

Tried on another install of CertOS (different machine) got this:

[root@localhost ~]# tar zxvf mdadm-2.6.tgz
mdadm-2.6/
mdadm-2.6/util.c
mdadm-2.6/ANNOUNCE-2.0
mdadm-2.6/ANNOUNCE-2.4.1
mdadm-2.6/ANNOUNCE-2.1
mdadm-2.6/Assemble.c

gzip: stdin: invalid compressed data--format violated
tar: Unexpected EOF in archive
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now

Is mdadm installed already, perhaps? What happens when you run 'mdadm' from the command line? That "nothing to do" sounds like it's already done it.

Hmmm...well kick me in the head and call me retarded....the one thing I didn't try :-/ haha. Alright now comes the fun. I'll see if I can figure this out. If not then I'll post again. Thanks for pointing out the obvious to me ;-)

Alright stupid Linux user question. How can I list the hdds and where they are mounted so I know which I'm adding to the array?

thnx

You can do "fdisk -l" to display what disks and partitions there are.

Does that distro have support for installing to md volumes? That would greatly simplify things as compared to migrating your existing install.

Ok, ignore the last question google is always a good help. Here is the next question. Can I create a RAID array with two drives that are already in the computer and already in use? I tried "mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /devsdb1" that gaves me

"
md: could not bd_claim sda1
md: error, md_import_device() returned -16
mdadm: ADD_NEW_DISK for /dev/sda1 failed: Devices or resource busy
"

Yay, another fun issue :-D

What it appears you'll need to do is create a broken raid1 array (use "missing" instead of a device name), copy the data from the corresponding device, and add that device to the raid 1 array. See this tutorial for how to do this on another Linux distro.

I'm downloading trixbox right now. If you run into problems I'll go through and get step-by-step instructions.

Cool. Just following the instructions for installing the RAID on the box right now.

Ran into a little problem I'm assuming that we don't want to use this software RAID with the RAID that is onboard the mobo right? Cause I just created the partitions, rebooted to activate the table and it went all fubar. So I'm removing the drives from the mobo RAID, reinstalling and trying just mdadm.

Correct. It sounds like the motherboard's software raid wasn't working - you shouldn't've been able to see two drives in Linux - but it could conflict with mdadm and cause problems.

Still downloading - sourceforge is being slow today

Wow, it crashes really hard when I change the partitions on the 2nd drive. even from a fresh install it breaks it good. gives me a kernel panic, I'm going to try an install with just the one hdd attached to make sure that the software hasn't been altered and trying to write something to the 2nd hdd. This sucks :-/

Ehh....I've reached Step 7, it asks for "palo -f /mnt/etc/palo.conf -I /dev/sdb". Tried that, I get "-bash: palo: command not found".....ehhhh :-/

palo is the boot loader for that particular architecture. If you're using grub or lilo, they fill a similar role. Try grub-install (hd1) or setup lilo to write to /dev/sdb in /etc/lilo.conf.

Dang, it took me way too long to type that. Kept trying to tab-complete

Thanks. I'll try that tomorrow right when I get into work. Hope that is going to work for me.

What would be the full command that I would use in place of palo?

Thanks for sticking with the newb on this one ;-)

I'm seriously having no luck figuring out the commands to make this work in grub. Tried to go into Grub and enter the following:

grub> root (hd1,1)
Filesystem type is ext2fs, partition type 0xfd

grub> kernel /vmlinux root=/dev/md2

Error 15: File not Found

grub> kernel /vmlinux root=/dev/sdb2

Error 15: File not Found


Now I'm stuck between a rock and a hard place again :-/ I'm going to keep trying random commands in grub to see if I can get it to recognize :-/

Thanks.

I found an article on trixbox.org that says the easiest way to do it is to create a new kickstart file on the iso, reburn the CD and go from there. I'm going to try that, should work no problem (crossing fingers) and I'll post back. Going to take a bit since I need to search for a freeware ISO editor tough to find.

thanks again., oh here is the linky:

http://www.trixbox.org/modules/newbb...er=ASC&start=0